The authors gratefully acknowledge financial support from the Belgian Federal government (Belspo through the IAP VI/27 and IAP-7/05 programs), the European Union's Seventh Framework Programme (FP7/2007-2013 under grant agreement no. 310651 SACS), the Flemish government in the form of long-term structural funding "Methusalem" grant METH/08/04 CASAS, the "Strategisch Initiatief Materialen" SoPPoM program, and the Fund for Scientific Research Flanders (FWO) grant G.0349.12. W.B. gratefully acknowledge the chemistry department of the KU Leuven for a FLOF-scholarship. The authors thank UOP Antwerp for the kind donation of zeolite samples and the mechanical workshop of the KU Leuven for helping with the design and construction of the heating/vacuum cell used in this study.

注意：このレポートで使用される化学物質および試薬は、適切な安全保護（白衣、手袋、安全ゴーグル、ヒュームフード）を使用して、注意して取り扱われました。本研究では、微多孔性無機材料（1から5ミクロンの範囲のサイズを有するゼオライト）の操作を扱うので、特別な注意が適切な防じん（防塵マスク）の使用を対象としました。我々は、適切な操作および/または廃棄物処理のために使用する前に、この作業に用いられる化学物質および試薬の関連材料の安全性データ（MSDS）の相談をお勧めします。 1.ゼオライトの前処理<ol><li>熱前処理 注：銀クラスター形成や発光を妨げる可能性があり、このような有機不純物などの不純物を、除去するために、使用前にゼオライト材料を事前に扱います。 <ol><li>商業LTA（NA）ゼオライトの10グラムを計量し、デポ（商業LTAゼオライトは、カウンターバランスそのフレームワーク中のイオンとしてナトリウムが含まれています）磁器トレイ上に均一に座ります。 </li><li>ゼオライト構造の損傷を避けるために80°Cと110°Cで1時間の間隔で5℃/分の温度傾斜を用いて、450℃のマッフル炉中で一晩ゼオライト粉末を加熱します。 </li><li>オーブンからゼオライト材料を取り外し、それは周囲条件下で室温まで冷却しましょう。 </li></ol></li><li>ゼオライト粒子のサイズ選択 注：これは、均質なフィルムを作成するために必要な出発ゼオライト材料のより均一な粒度分布を生成します。このステップは、多くの場合、工業的に製造さゼオライト中に存在している大規模な非晶質粒子を除去します。 <ol><li>商業LTA（NA）を10gを秤量し、脱イオン水1L中に懸濁します。 </li><li>積極的に手で10分ごとにサスペンションを振っ、1時間サスペンションを超音波処理。 </li><li> 30分間Atterbergシリンダ（1 L）中懸濁液を注ぎます。サイズは10ミクロン未満の粒子懸濁液中に残っているが、より大きな粒子が沈殿します。 </li><li>サスペンションをデカントし、ブフナー漏斗を用いて濾過することにより粉末を回収します。脱イオン水で回収した粉末を3回洗浄します。 </li><li>熱ステップ1.1.2で説明したように粉末を扱います。 </li></ol></li></ol>発光LTA（ナ）-Agゼオライト複合材料の作製<ol><li>発光銀の合成は、参考資料として[LTA（ナ）-Ag] LTAゼオライトを交換しました<ol><li> 250ミリリットル高密度ポリプロピレン（HDPE）ボトルに脱イオン水200ミリリットル中の硝酸銀の74.8ミリグラムを溶解させます。 </li><li>前処理LTA（NA）試料1gを秤量し、硝酸銀溶液中に懸濁します。 </li><li>室温で転倒型シェーカーオーブンに一晩攪拌HDPEフラスコを残します。 </li><li>ブフナー漏斗を用いて懸濁液を濾過し、脱イオン水でゼオライト粉末を3回洗浄します。 </li><li> 45時マッフル炉中で回収した粉末を加熱ステップ1.1.2に記載したのと同じ手順を用いて、0℃、。 </li><li>サンプルを冷却し、制御された湿度（相対湿度98％）でデシケーターに入れてください。デシケーター内部の飽和硫酸カリウム溶液を配置することによって相対湿度を制御します。15 </li><li>分光蛍光光度計ならびにそれらの外部量子効率を用いて、（異なる波長で）サンプルの励起および発光スペクトルを測定します。 <ol><li> 1ミリメートルパス石英キュベットにサンプルを配置することによって、2次元励起 - 発​​光プロットを測定します。 5nmのステップおよび0.1秒の滞留時間を用いて800 nmの励起波長、最大上に30nm出発発光スペクトルを収集します。 </li><li>ランプ強度と生データへの放出経路の波長依存性の検出のための機器のソフトウェアを使用して修正を適用します。さらに、2次元プロットで二次ピークを避けるために、ロングパスフィルターを使用しています。 </li><li>量子efficiを実行しますその後encyの分光蛍光光度計に取り付けられた積分球を使用して測定。16録音ゼオライトサンプルと励起波長として260nmのを使用してのBaSO 4参照の両方のための600 nmの240 nmでの放射スキャン、および機器のソフトウェアを使用して量子効率を計算します。 </li></ol></li></ol></li></ol>発光[LTA（李）-Ag]ゼオライト複合材料の調製<ol><li>部分的に交換されたリチウムLTAゼオライトの合成[LTA（李）] 注：手順は八尋と共同研究者の報告書から適応された部分的に交換LTA（Li）とゼオライトの製造に続いて17。 <ol><li> 2.5 Lの脱イオン水に17.2グラムの硝酸リチウムを溶解させます。 </li><li> 1LのHDPEフラスコに硝酸リチウム溶液0.5 Lを注ぎます。 </li><li>前処理LTA（NA）ゼオライトを3gを秤量し、硝酸リチウム溶液を含むHDPEフラスコ中に懸濁します。 </li><li>エンド-Oを用いてフラスコを撹拌室温で一晩版エンドシェーカーオーブン。 </li><li>ブフナー漏斗を用いて懸濁液を濾過し、脱イオン水を用いて回収した粉末を3回洗浄します。 </li><li>リチウム交換を行います<ol><li>濾過工程（3.1.5）から回収した粉末を含む1LのHDPEフラスコに新鮮な硝酸リチウム溶液（3.1.1）の0.5 Lを追加します。 </li><li>繰り返しは、3.1.4と3.1.5を繰り返します。 </li><li>繰り返しは、3.1.6.1と3.1.6.2別の4回繰り返します。 </li></ol></li><li>ゼオライト粉末を回収し、一晩80°Cと110°Cで1時間の間隔で5℃/分の温度傾斜を用いて、450℃のマッフル炉中で加熱します。 </li></ol></li><li>発光の合成[LTA（李）-Ag]ゼオライト<ol><li> 250ミリリットルHDPEボトルを使用して、脱イオン水200ミリリットルで74.8 mgの硝酸銀を溶解させます。 </li><li>部分的に交換されたリチウムLTAゼオライト[LTA（李）]の1グラムを計量し、硝酸銀溶液（3.2.1）にそれを中断。 </li><li> HDPE FLを攪拌室温で一晩転倒型振とうオーブンを使用してお願いします。 </li><li>ブフナー漏斗を用いて懸濁液を濾過し、脱イオン水を用いて回収したゼオライト粉末を3回洗浄します。 </li><li>一晩80℃〜110℃で1時間の間隔で5℃/分の温度勾配を使用して、450℃のマッフル炉中で粉末を熱処理します。 </li><li>内部飽和硫酸カリウム溶液（98％相対湿度）を含むデシケータを用いて制御された湿度条件下でサンプルを冷却15 </li><li>ステップ2.1.7に記載の手順に従って、サンプルの励起および発光スペクトルならびにそれらの外部量子効率を測定します。 </li><li> 、1簡単に言えば。異なる温度で、試料中の水分含有量を決定するために、熱重量分析（TGA）を行い、白金試料ホルダーにとして、調製した試料の30〜50ミリグラムを配置し、TGAデバイスにロードします。 50からの重量損失を測定します°C、600°Cまで窒素流（90 ml /分）下に5℃/分の加熱速度を使用して。 </li></ol></li></ol>湿度検出アプリケーションのためのLTA（李）-Ag /ポリエチレンイミン（PEI）複合蒸着膜の4製作注：このレポートで使用される堆積手順が変更され、基準18から適応されました。 <ol><li> LTA（李）-Agコロイド懸濁液の準備。 <ol><li>脱イオン水で100mlに商用50重量％PEI溶液1mlを希釈します。 </li><li>発光LTA（李）-Ag材料250mgの重量を量ります。 </li><li> 125ミリリットルのHDPEボトルで一緒にゼオライトとPEI溶液を混合し、積極的にサスペンションを振ります。 </li><li>均一な懸濁液を得るために、室温で一晩40 kHzの超音波洗浄器でボトルを置きます。 </li><li>スプレーボトルにLTA（李）-Ag / PEI懸濁液を注ぎます。 </li></ol></li><li>センサーPROTのための石英板上にLTA（李）-Ag / PEI膜の堆積otypeの生産。 <ol><li>前の成膜に、連続的に脱イオン水及びアセトンでそれをすすぐことによって石英板を清掃してください。 1時間80℃のオーブンできれいなプレートを乾燥させます。 </li><li>アルミニウム箔のクリーンシートに水平石英板を配置し、約20cmの距離から三回（3秒毎に）噴霧することにより、一方の側にコートに石英板をスプレー。 50℃で30分間乾燥炉内部のコーティングされたプレートを置きます。 </li><li>フィルムが均一になるまで繰り返しステップは、別の4回4.2.2。 </li></ol></li><li>センサーのプロトタイプの水和/脱水。 <ol><li>社内加熱/真空セルのサンプルコンパートメントにコーティングされた石英板を配置します。5 </li><li>コーティングされたプレートの上にゴムリングとの組み合わせできれいな石英板を配置することによって、細胞の試料室を閉じ、 図2に示すように、テフロンストッパーとネジを使用してセルを密封します。 </li><li>高真空を適用し、私たちサンプルを脱水するために、細胞を一晩に、10 -3ミリバール未満の圧力をる。 </li><li>視覚的にUVランプを使用して堆積膜（可視光領域）の発光色の変化を監視します。 </li><li> UVランプを用いて膜の再水和の際に、可視領域の発光色の変化を監視するために試料室を開きました。 </li><li> LTA（李）-Ag / PEIフィルムの可逆性をテストするために、ステップ4.3.2から4.3.5に始まるサイクルを複数回繰り返します。 </li></ol></li></ol>

<ol>
	<li>De Cremer, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+Fluorescence+in+Heat-Treated+Silver-Exchanged+Zeolites.">Characterization of Fluorescence in Heat-Treated Silver-Exchanged Zeolites.</a> J. Am. Chem. Soc. 131, 3049-3056 (2009).</li><li>De Cremer, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optical+Encoding+of+Silver+Zeolite+Microcarriers.">Optical Encoding of Silver Zeolite Microcarriers.</a> Adv. Mater. 22, 957-960 (2010).</li><li>Coutino-Gonzalez, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=X-ray+Irradiation-Induced+Formation+of+Luminescent+Silver+Clusters+in+Nanoporous+Matrices.">X-ray Irradiation-Induced Formation of Luminescent Silver Clusters in Nanoporous Matrices.</a> Chem. Commun. 50, 1350-1352 (2014).</li><li>De Cremer, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=In+Situ+Observation+of+the+Emission+Characteristics+of+Zeolite-Hosted+Silver+Species+During+Heat+Treatment.">In Situ Observation of the Emission Characteristics of Zeolite-Hosted Silver Species During Heat Treatment.</a> ChemPhysChem. 11, 1627-1631 (2010).</li><li>Coutino-Gonzalez, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermally+Activated+LTA(Li)-Ag+Zeolites+with+Water-Responsive+Photoluminescence+Properties.">Thermally Activated LTA(Li)-Ag Zeolites with Water-Responsive Photoluminescence Properties.</a> J. Mater. Chem. C. 3, 11857-11867 (2015).</li><li>Seifert, R., Kunzmann, A., Calzaferri, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Yellow+Color+of+Silver-Containing+Zeolite.">The Yellow Color of Silver-Containing Zeolite.</a> A. Angew. Chem. Int. Ed. 37, 1522-1524 (1998).</li><li>Seifert, R., Calzaferri, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Colors+of+Ag+-Exchanged+Zeolite+A.">Colors of Ag+-Exchanged Zeolite A.</a> J. Phys. Chem. A. 104, 7473-7483 (2000).</li><li>Sazama, P., Jirglova, H., Dedecek, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ag-ZSM-5+Zeolite+as+High-Temperature+Water-Vapor+Sensor+Material.">Ag-ZSM-5 Zeolite as High-Temperature Water-Vapor Sensor Material.</a> Mat. Lett. 62, 4239-4241 (2008).</li><li>Zheng, Y., Li, X., Dutta, P. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exploitation+of+Unique+Properties+of+Zeolites+in+the+Development+of+Gas+Sensors.">Exploitation of Unique Properties of Zeolites in the Development of Gas Sensors.</a> Sensors. 12, 5170-5194 (2012).</li><li>Sun, T., Seff, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Silver+Clusters+and+Chemistry+in+Zeolites.">Silver Clusters and Chemistry in Zeolites.</a> Chem. Rev. 94, 857-870 (1994).</li><li>Yu, Y., Ma, J. P., Dong, Y. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Luminescent+Humidity+Sensors+Based+on+Porous+Ln3+-MOFs.">Luminescent Humidity Sensors Based on Porous Ln3+-MOFs.</a> Cryst. Eng. Comm. 14, 7157-7160 (2012).</li><li>Qi, H., Mader, E., Liu, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Unique+Water+Sensors+Based+on+.">Unique Water Sensors Based on .</a> Sensor. Actuat. B-Chem. 185, 225-230 (2013).</li><li>Basabe-Desmonts, L., Reinhoudt, D. N., Crego-Calama, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+of+Fluorescent+Materials+for+Chemical+Sensing.">Design of Fluorescent Materials for Chemical Sensing.</a> Chem. Soc. Rev. 36, 993-1017 (2007).</li><li>Yamazoe, N., Shimzu, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Humidity+Sensors+-+Principles+and+Applications.">Humidity Sensors - Principles and Applications.</a> Sensor. Actuator. 10, 379-398 (1986).</li><li>International Organization of Legal Metrology. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Scale of Relative Humidity of Air Certified Against Saturated Salt Solutions. , (1996).</li><li>Coutino-Gonzalez, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+and+Optimization+of+the+Luminescent+External+Quantum+Efficiency+of+Silver-Clusters+Zeolite+Composites.">Determination and Optimization of the Luminescent External Quantum Efficiency of Silver-Clusters Zeolite Composites.</a> J. Phys. Chem. C. 117, 6998-7004 (2013).</li><li>Yahiro, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=EPR+Study+on+NO+Introduced+into+Lithium+Ion-Exchanged+LTA+Zeolites.">EPR Study on NO Introduced into Lithium Ion-Exchanged LTA Zeolites.</a> Phys. Chem. Chem. Phys. 4, 4255-4259 (2002).</li><li>Shelyakina, M. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Study+of+Zeolite+Influence+on+Analytical+Characteristics+of+Urea+Biosensor+Based+on+Ion-Selective+Field-Effect+Transistors.">Study of Zeolite Influence on Analytical Characteristics of Urea Biosensor Based on Ion-Selective Field-Effect Transistors.</a> Nanoscale Res. Lett. 9, 124 (2014).</li></ol>

The authors have nothing to disclose.

A simple device to demonstrate the proof of concept of using LTA(Li)-Ag as a luminescence based humidity sensor was produced by spray coating the LTA(Li)-Ag powder suspended in a PEI solution onto a quartz plate. The PEI solution produces a polymer layer with homogenous thickness when the water is evaporated. The polymer-zeolite composite layer displays similar luminescent properties as that of the zeolite in powder form. The PEI/LTA(Li)-Ag zeolite composite displays the expected water-responsive luminescent properties, whose emission color changes upon variations in the water content present in the composite at relatively low humidity scale. 
Replacing Na with Li ions in LTA zeolites (calculated exchange rate 33%) has a notable impact on the self-assembly and stabilization of luminescent silver clusters in the LTA(Li) scaffolds leading to unique optical properties. The EQE of LTA(Li)-Ag as compared to LTA(Na)-Ag samples is enhanced by more than one order of magnitude. Moreover, the emission colors displayed by the LTA(Li)-Ag samples have a water-dependence, providing a potential application of the samples as luminescence based humidity sensors. 
We have thus demonstrated an easy method to fabricate a luminescent film-like humidity sensor through which changes in hydration levels can be visually monitored simply by using a UV lamp. The availability of the raw materials, the direct visualization of the color changes correlated with humidity content, the photo-stability of the films, and the relative ease of fabricating cost-effective devices make these luminescent materials potential candidates to compete with state-of-the-art humidity sensors based upon electrical responses. The procedure described in this report could also be applied and extended to different substrates, at different micro and macro scales, to make the sensor more flexible. Additionally, several critical steps during the fabrication of Ag-zeolites, which play an important role in determining the final optical properties of such materials, were discussed in this protocol. For instance, the pre-cleaning of the raw zeolite material leads to the removal of optical and chemical impurities, as well as to homogenous zeolite crystal size distribution. This is crucial for the incorporation of zeolites into functional devices. One limitation of the present methodology is the restriction on the use of thin film sensors beyond 75 &#176;C. This is mainly due to the decomposition of the PEI polymer, rather than to the degradation of the LTA(Li)-Ag zeolites, which can withstand up to 500 &#176;C. The use of heat-resistant polymers, such as polyvinyl alcohol, could expand the temperature range up to 200 &#176;C. We expect that further investigations will be directed to the development of methodologies for the synthesis of nanostructured Ag-zeolite composites with (multi)functional properties and finally to the design of advanced sensor prototypes.

閉じ込められたゼオライトマトリックス中に自己組織化によって形成された小サブナノメートルoligoatomic銀クラスターは、独自の光学特性を示す。1-5このような銀-ゼオライト複合材料は、高い化学的及び光安定性を有します。しかしながら、それらの光ルミネセンス特性は銀クラスターのローカル環境に大きく依存しています。銀ゼオライト複合体に光学的特徴に影響を与える環境条件に内因性および外因性の特性に分けることができます。固有特性は、ゼオライトトポロジー、カウンターバランスするイオンの種類、および銀の負荷に関連している。1一方、外因性の性質は、そのような中で吸着物や水分子の存在などの合成後の変化に関連していますゼオライトの空洞。3,4後者の特性は、銀ゼオライトに与えるには、光学的に、このようなゼオライト足場6-8内の水分の変動のような外部刺激に応答する能力を合成します</suP&gt;または決定されたガスの存在。したがって、水蒸気およびガスセンサーとしてのそれらの使用が提案されている。9,10 最近の研究では、湿気に銀ゼオライトの光学応答が唯一の彼らの放射の吸収または消光の変化にも、それらの含水量に対して異なる発光色の外観に相関されていないことを実証している。5安定化部分的にLiがLTAゼオライトは、それぞれ、脱水および水和試料中の緑/黄色発光する青色から動的な色の変化に反映された相対湿度の低いスケールで変化する水分応答性材料の形成につながっ交換で銀クラスターの。したがって、発光ベース湿度センサとして、これらの材料を使用することが提案されました。今日まで、このような電解質、セラミック、ポリマー、およびナノ構造複合材料などの材料の異なるタイプの湿度Bにおける監視変更が提案されています電気的および光学的応答に関するASED。11,12この詳細なプロトコルでは、我々は、湿度センサとしてLTA（李）-Agゼオライトの応用のために、さらにプロトタイプの開発に、概念実証を実証することを目指しています。 LTA（李）-Agゼオライトの汎用性のために、異なる基板に組み込まれるように、彼らの潜在的な拡張性と費用対効果の製造は、プロトタイプの設計を容易にする可能性があります。13このようなセンサは、のように、異なる産業分野での適用可能性を持つことができます農業だけでなく、自動車、製紙産業。14

<table border="0" cellpadding="0" cellspacing="0" width="833">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:268px;">LTA(Na) zeolite</td>
			<td style="width:169px;">UOP</td>
			<td style="width:167px;">Molsiv adsorbent 4A</td>
			<td style="width:229px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Silver nitrate</td>
			<td>Sigma Aldrich</td>
			<td>209139</td>
			<td>&#8805;99,0%</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Lithium nitrate</td>
			<td>Sigma Aldrich</td>
			<td>62574</td>
			<td>&#8805;99,0%, calc. on dry substances</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Polyethyleneimine solution</td>
			<td>Sigma Aldrich</td>
			<td>3880</td>
			<td>~50% H2O</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Scanning electron microscope (SEM)</td>
			<td>JEOL</td>
			<td>JSM-6010LV</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Thermogravimetric analyzer</td>
			<td>TA instruments</td>
			<td>Q500</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Spectrofluorimeter</td>
			<td>Edinburgh instruments</td>
			<td>FLS980-s</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Integrating sphere</td>
			<td>Labsphere</td>
			<td>4P-GPS-033-SL</td>
			<td></td>
		</tr>
	</tbody>
</table>

nanostructured ag-zeolite composites as luminescence-based humidity sensors

Small silver clusters confined inside zeolite matrices have recently emerged as a novel type of highly luminescent materials. Their emission has high external quantum efficiencies (EQE) and spans the whole visible spectrum. It has been recently reported that the UV excited luminescence of partially Li-exchanged sodium Linde type A zeolites [LTA(Na)] containing luminescent silver clusters can be controlled by adjusting the water content of the zeolite. These samples showed a dynamic change in their emission color from blue to green and yellow upon an increase of the hydration level of the zeolite, showing the great potential that these materials can have as luminescence-based humidity sensors at the macro and micro scale. Here, we describe the detailed procedure to fabricate a humidity sensor prototype using silver-exchanged zeolite composites. The sensor is produced by suspending the luminescent Ag-zeolites in an aqueous solution of polyethylenimine (PEI) to subsequently deposit a film of the material onto a quartz plate. The coated plate is subjected to several hydration/dehydration cycles to show the functionality of the sensing film.

LTA-銀ゼオライトのSEM顕微鏡写真は、陽イオン交換および熱処理工程の後に記録しました。続いてフォトルミネセンス、二次元（2D）の励起/放射プロットは、水和LTA（NA）-Ag及びLTA（リー）-Agゼオライト（ 図1）の両方を測定しました。 Agは、その化学組成を決定するために、ゼオライトを交換の元素分析は、XPSにより行いました。解析はLTA（NA）とLTA（Li）とゼオライトに銀交換はそれぞれ19.6重量％および21.5重量％の銀重量パーセントと非常に近いことを示しています。重量百分率の差は、Li原子の低い原子量に帰することができます。さらに、元素分析は、リチウム交換後のナトリウムの33％が置換されることが示されました。陽イオン交換およびサンプル上で実行される後続の熱処理工程は、SEMによって示されるように、LTA結晶の構造に影響を与えていないように見えます。また、より大きな銀の形成のnゼオライト結晶の表面上anoparticlesが可視化されていませんでした。発光特性は、主にその水和状態で両方のLTA（李）-AgとLTA（NA）-Agサンプル間で異なります。カウンターバランス陽イオンとしてゼオライト骨格にリチウムを組み込むことにより、励磁最大でブルーシフトは、LTA（NA）-AgとLTA（李）-Agため、それぞれ、波長370nmから260nmのが原因で発生します。これとは対照的に発光極大は、システムにリチウムを添加することにより、565 nmの550から小さな赤方偏移を受けます。これらのサンプルの間の最大の違いは、それらの外部量子効率（EQE）で観察されます。 （260 nmで励起したとき）LTAのためのEQE（李）-Agゼオライトが62％に達したのに対し、LTA（ナ）-Agゼオライトは、その最大励起（370 nm）ので約4％のEQEを有しています。これは、254nmの紫外線照射下で明るい黄色の発光粉末になります。 LTA（リー）-Ag試料の発光特性はまた、水の含有量に依存していますシステム。これは、TGAおよび温度に依存する発光実験の組み合わせによって示された、TGAは、ゼオライトの水和レベルまで温度を相関させます。さらに、温度は、社内加熱セルを使用して、LTA（李）-Agサンプル（ 図2）によって表示される発光色に間接的に関係しました。緑色から青色に黄色の発光色がシフトし、LTA（李）-Ag系から水を除去します。 EQEは着実に21％（脱水状態）に62％（含水状態）から降下します。 なぜならLTA（リー）-Agの水応答性挙動を、この材料はPEI溶液中に粉末を懸濁し、続いて、石英板上に複合材料をスプレーコーティングすることにより、発光ベースの湿度センサのプロトタイプを作製しました。 （昼光とUV照射下）の写真やスプレー塗装LTA（李）-Ag / PEIフィルムのSEM顕微鏡写真を図3に表示されている。我々は、USIによってことを観察しました<html> NGこのコーティング手順、発光面でのポリマー - ゼオライト複合体の比較的均一な層が得られました。 SEM顕微鏡写真は、ゼオライト結晶をコーティング手順によって変更されないことを示しています。社内加熱/真空セルを使用して、それはまた、ポリマー - ゼオライトフィルムは、粉末形態でゼオライトで観察された水の応答特性を保持することが示されました。 <img alt="図1" src="/files/ftp_upload/54674/54674fig1.jpg" /> 図1：SEM 写真と銀の発光特性は、LTAゼオライトのSEM顕微鏡写真およびLTA（ナ）-Ag（b）およびLTA（李）-Ag（C、D）の2次元励起発光プロットを交換しました。 2D励起 - 発​​光プロットにおける挿入図は、異なる励起波長（254、300、366および450 nm）の下でのサンプルのシミュレートされた発光色を表示します。<html> OAD / 54674 / 54674fig1large.jpg &quot;ターゲット=&quot; _空白 &quot;&gt;この図の拡大版をご覧になるにはこちらをクリックしてください。 <img alt="図2" src="/files/ftp_upload/54674/54674fig2.jpg" /> 図2：LTA（ 李）-Agの発光特性上の水和レベルの効果。 。。LTA（Li）との260 nmの励起時LTA（李）-Agサンプルc）の正規化された発光スペクトル（）のために、この研究b）の TGAプロットで採用、社内加熱/真空セルのa）の模式図- Agのサンプルは、異なる温度で測定した。d）のスキームの水含有量に関して実際のサンプルの発光色の変化を表示する。 <a href="https://ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54674/54674fig2large.jpg" target="_blank">この図の拡大版をご覧になるにはこちらをクリックしてください。</a> ftp_upload / 54674 / 54674fig3.jpg &quot;/&gt; 図3：LTA（ 李）-Ag / PEI複合に基づいて発光湿度センサ。 a）は、昼光照明の下でコーティングされたプレートの写真。 （B、C）石英表面上のLTA（李）-Ag結晶の分布を示す堆積膜のそれぞれ脱水および水和コーティングされたプレートの写真254 nmのUV光照射下、。d）の SEM写真。挿入図は、元のSEM写真の選択した領域を拡大して表示されます。水和、脱水PEI / LTAのe）の排出量の最大値（Li）と-Agゼオライト複合、励起波長として260nmのを使用して、10の水和/脱水サイクル中。f）の PEI / LTA（李）10水和/脱水サイクル後-Agゼオライト複合体の発光極大プロファイルの挙動を示すプロット。 <a href="https://ecsource-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/54674/54674fig3large.jpg" target="_blank">viにはこちらをクリックしてください</a>この図の拡大版をEW。

Watch this Scientific Journal Video about Nanostructured Ag-zeolite Composites as Luminescence-based Humidity Sensors at JoVE.com

Nanostructured Ag-zeolite Composites as Luminescence-based Humidity Sensors

A protocol for the synthesis of moisture-responsive luminescent Ag-zeolite composites is described in this report.

発光ベースの湿度センサなどのナノ構造のAg-ゼオライト複合

Small silver clusters confined inside zeolite matrices have recently emerged as a novel type of highly luminescent materials. Their emission has high ...

nanostructured-ag-zeolite-composites-as-luminescence-based-humidity

Nanyang Technological University

Research

JoVE Journal

Engineering

10.1K ビュー.  KU Leuven. A protocol for the synthesis of moisture-responsive luminescent Ag-zeolite composites is described in this report.

ビデオ: Nanostructured Ag-zeolite Composites as Luminescence-based Humidity Sensors

Development of Whispering Gallery Mode Polymeric Micro-optical Electric Field Sensors

Optical modes of dielectric micro-cavities have received significant attention in recent years for their potential in a broad range of applications. The optical modes are frequently referred to as "whispering gallery modes" (WGM) or "morphology dependent resonances" (MDR) and exhibit high optical quality factors. Some proposed applications of micro-cavity optical resonators are in spectroscopy1, micro-cavity laser technology2, optical communications3-6 as well as sensor technology. The WGM-based sensor applications include those in biology7, trace gas detection8, and impurity detection in liquids9. Mechanical sensors based on microsphere resonators have also been proposed, including those for force10,11, pressure12, acceleration13 and wall shear stress14. In the present, we demonstrate a WGM-based electric field sensor, which builds on our previous studies15,16. A candidate application of this sensor is in the detection of neuronal action potential.
The electric field sensor is based on polymeric multi-layered dielectric microspheres. The external electric field induces surface and body forces on the spheres (electrostriction effect) leading to elastic deformation. This change in the morphology of the spheres, leads to shifts in the WGM. The electric field-induced WGM shifts are interrogated by exciting the optical modes of the spheres by laser light. Light from a distributed feedback (DFB) laser (nominal wavelength of ~ 1.3 &mu;m) is side-coupled into the microspheres using a tapered section of a single mode optical fiber. The base material of the spheres is polydimethylsiloxane (PDMS). Three microsphere geometries are used: (1) PDMS sphere with a 60:1 volumetric ratio of base-to-curing agent mixture, (2) multi layer sphere with 60:1 PDMS core, in order to increase the dielectric constant of the sphere, a middle layer of 60:1 PDMS that is mixed with varying amounts (2% to 10% by volume) of barium titanate and an outer layer of 60:1 PDMS and (3) solid silica sphere coated with a thin layer of uncured PDMS base. In each type of sensor, laser light from the tapered fiber is coupled into the outermost layer that provides high optical quality factor WGM (Q ~ 106). The microspheres are poled for several hours at electric fields of ~ 1 MV/m to increase their sensitivity to electric field.

A high-sensitivity photonic micro sensor was developed for electric field detection. The sensor exploits the optical modes of a dielectric sphere. Changes in the external electric field perturb the sphere morphology leading to shifts in its optical modes. The electric field strength is measured by monitoring these optical shifts.

ギャラリーモード高分子マイクロ光電界センサを囁くの開発

Optical modes of dielectric micro-cavities have received significant attention in recent years for their potential in a broad range of applications. The ...

工学

A Testing Platform for Durability Studies of Polymers and Fiber-reinforced Polymer Composites under Concurrent Hygrothermo-mechanical Stimuli

The durability of polymers and fiber-reinforced polymer composites under service condition is a critical aspect to be addressed for their robust designs and condition-based maintenance. These materials are adopted in a wide range of engineering applications, from aircraft and ship structures, to bridges, wind turbine blades, biomaterials and biomedical implants. Polymers are viscoelastic materials, and their response may be highly nonlinear and thus make it challenging to predict and monitor their in-service performance. The laboratory-scale testing platform presented herein assists the investigation of the influence of concurrent mechanical loadings and environmental conditions on these materials. The platform was designed to be low-cost and user-friendly. Its chemically resistant materials make the platform adaptable to studies of chemical degradation due to in-service exposure to fluids. An example of experiment was conducted at RT on closed-cell polyurethane foam samples loaded with a weight corresponding to ~50% of their ultimate static and dry load. Results show that the testing apparatus is appropriate for these studies. Results also highlight the larger vulnerability of the polymer under concurrent loading, based on the higher mid-point displacements and lower residual failure loads. Recommendations are made for additional improvements to the testing apparatus.

The durability of polymers and fiber-reinforced polymer composites in service is a critical aspect for their designs and condition-based maintenance. We present a novel low-cost laboratory testing platform for the investigation of the influence of concurrent mechanical and environmental loadings, and may help design more efficient yet safer composite structures.

同時Hygrothermo-機械的刺激下でのポリマーおよび繊維強化ポリマー複合材料の耐久性研究のための試験プラットホーム

The durability of polymers and fiber-reinforced polymer composites under service condition is a critical aspect to be addressed for their robust designs ...

Preparation and Reactivity of Gasless Nanostructured Energetic Materials

High-Energy Ball Milling (HEBM) is a ball milling process where a powder mixture placed in the ball mill is subjected to high-energy collisions from the balls. Among other applications, it is a versatile technique that allows for effective preparation of gasless reactive nanostructured materials with high energy density per volume (Ni+Al, Ta+C, Ti+C). The structural transformations of reactive media, which take place during HEBM, define the reaction mechanism in the produced energetic&#160;composites. Varying the processing conditions permits fine tuning of the milling-induced microstructures of the fabricated composite particles. In turn, the reactivity, i.e., self-ignition temperature, ignition delay time, as well as reaction kinetics, of high energy density materials depends on its microstructure. Analysis of the milling-induced microstructures suggests that the formation of fresh oxygen-free intimate high surface area contacts between the reagents is responsible for the enhancement of their reactivity. This manifests itself in a reduction of ignition temperature and delay time, an increased rate of chemical reaction, and an overall decrease of the effective activation energy of the reaction. The protocol provides a detailed description for the preparation of reactive nanocomposites with tailored microstructure using short-term HEBM method. It also describes a high-speed thermal imaging technique to determine the ignition/combustion characteristics of the energetic materials. The protocol can be adapted to preparation and characterization of a variety of nanostructured energetic composites.

This protocol describes the preparation of gasless nanostructured energetic materials (Ni+Al, Ta+C, Ti+C) using the short-term high-energy ball milling (HEBM) technique. It also describes a high-speed thermal imaging method to study the reactivity of mechanically fabricated nanocomposites. These protocols can be extended to other reactive nanostructured energetic materials.

Gaslessナノエネルギー物質の調製と反応性

High-Energy Ball Milling (HEBM) is a ball milling process where a powder mixture placed in the ball mill is subjected to high-energy collisions from the ...

Surface Enhanced Raman Spectroscopy Detection of Biomolecules Using EBL Fabricated Nanostructured Substrates

Fabrication and characterization of conjugate nano-biological systems interfacing metallic nanostructures on solid supports with immobilized biomolecules is reported. The entire sequence of relevant experimental steps is described, involving the fabrication of nanostructured substrates using electron beam lithography, immobilization of biomolecules on the substrates, and their characterization utilizing surface-enhanced Raman spectroscopy (SERS). Three different designs of nano-biological systems are employed, including protein A, glucose binding protein, and a dopamine binding DNA aptamer. In the latter two cases, the binding of respective ligands, D-glucose and dopamine, is also included. The three kinds of biomolecules are immobilized on nanostructured substrates by different methods, and the results of SERS imaging are reported. The capabilities of SERS to detect vibrational modes from surface-immobilized proteins, as well as to capture the protein-ligand and aptamer-ligand binding are demonstrated. The results also illustrate the influence of the surface nanostructure geometry, biomolecules immobilization strategy, Raman activity of the molecules and presence or absence of the ligand binding on the SERS spectra acquired.

We describe the fabrication and characterization of nano-biological systems interfacing nanostructured substrates with immobilized proteins and aptamers. The relevant experimental steps involving lithographic fabrication of nanostructured substrates, bio-functionalization, and surface-enhanced Raman spectroscopy (SERS) characterization, are reported. SERS detection of surface-immobilized proteins, and probing of protein-ligand and aptamer-ligand binding is demonstrated.

表面EBL作製したナノ構造基板を用いた生体分子のラマン分光検出の強化

Fabrication and characterization of conjugate nano-biological systems interfacing metallic nanostructures on solid supports with immobilized biomolecules ...

Preparation and Evaluation of Hybrid Composites of Chemical Fuel and Multi-walled Carbon Nanotubes in the Study of Thermopower Waves

When a chemical fuel at a certain position in a hybrid composite of the fuel and a micro/nanostructured material is ignited, chemical combustion occurs along the interface between the fuel and core materials. Simultaneously, dynamic changes in thermal and chemical potentials across the micro/nanostructured materials result in concomitant electrical energy generation induced by charge transfer in the form of a high-output voltage pulse. We demonstrate the entire procedure of a thermopower wave experiment, from synthesis to evaluation. Thermal chemical vapor deposition and the wet impregnation process are respectively employed for the synthesis of a multi-walled carbon nanotube array and a hybrid composite of picric acid/sodium azide/multi-walled carbon nanotubes. The prepared hybrid composites are used to fabricate a thermopower wave generator with connecting electrodes. The combustion of the hybrid composite is initiated by laser heating or Joule-heating, and the corresponding combustion propagation, direct electrical energy generation, and real-time temperature changes are measured using a high-speed microscopy system, an oscilloscope, and an optical pyrometer, respectively. Furthermore, the crucial strategies to be adopted in the synthesis of hybrid composite and initiation of their combustion that enhance the overall thermopower wave energy transfer are proposed.

A protocol for conducting thermopower wave experiments is presented. The synthesis of hybrid composites of a chemical fuel and micro/nanostructured material, manufacturing of a thermopower wave generator, and methods for measuring the corresponding physical phenomena are described.

熱電波の研究における化学燃料と多層カーボンナノチューブのハイブリッド複合材料の作製と評価

When a chemical fuel at a certain position in a hybrid composite of the fuel and a micro/nanostructured material is ignited, chemical combustion occurs ...

Iridium Oxide-reduced Graphene Oxide Nanohybrid Thin Film Modified Screen-printed Electrodes as Disposable Electrochemical Paper Microfluidic pH Sensors

A facile, controllable, inexpensive and green electrochemical synthesis of IrO2-graphene nanohybrid thin films is developed to fabricate an easy-to-use integrated paper microfluidic electrochemical pH sensor for resource-limited settings. Taking advantages from both pH meters and strips, the pH sensing platform is composed of hydrophobic barrier-patterned paper micropad (&#181;PAD) using polydimethylsiloxane (PDMS), screen-printed electrode (SPE) modified with IrO2-graphene films and molded acrylonitrile butadiene styrene (ABS) plastic holder. Repetitive cathodic potential cycling was employed for graphene oxide (GO) reduction which can completely remove electrochemically unstable oxygenated groups and generate a 2D defect-free homogeneous graphene thin film with excellent stability and electronic properties. A uniform and smooth IrO2 film in nanoscale grain size is anodically electrodeposited onto the graphene film, without any observable cracks. The resulting IrO2-RGO electrode showed slightly super-Nernstian responses from pH 2-12 in Britton-Robinson (B-R) buffers with good linearity, small hysteresis, low response time and reproducibility in different buffers, as well as low sensitivities to different interfering ionic species and dissolved oxygen. A simple portable digital pH meter is fabricated, whose signal is measured with a multimeter, using high input-impedance operational amplifier and consumer batteries. The pH values measured with the portable electrochemical paper-microfluidic pH sensors were consistent with those measured using a commercial laboratory pH meter with a glass electrode.

The study demonstrates the growth of iridium oxide-reduced graphene oxide (IrO2-RGO) nanohybrid thin films on irregular and rough screen-printed carbon substrate through a green electrochemical synthesis, and their implementation as a pH sensor with a patterned paper-fluidic platform.

使い捨て電気化学紙のマイクロ流体のpHセンサーとしてイリジウム酸化還元グラフェン酸化物ナノハイブリッド薄膜変更されたスクリーン印刷電極

A facile, controllable, inexpensive and green electrochemical synthesis of IrO2-graphene nanohybrid thin films is developed to fabricate an easy-to-use ...

Ultrasonic Welding of Thermoplastic Composite Coupons for Mechanical Characterization of Welded Joints through Single Lap Shear Testing

This paper presents a novel straightforward method for ultrasonic welding of thermoplastic-composite coupons in optimum processing conditions. The ultrasonic welding process described in this paper is based on three main pillars. Firstly, flat energy directors are used for preferential heat generation at the joining interface during the welding process. A flat energy director is a neat thermoplastic resin film that is placed between the parts to be joined prior to the welding process and heats up preferentially owing to its lower compressive stiffness relative to the composite substrates. Consequently, flat energy directors provide a simple solution that does not require molding of resin protrusions on the surfaces of the composite substrates, as opposed to ultrasonic welding of unreinforced plastics. Secondly, the process data provided by the ultrasonic welder is used to rapidly define the optimum welding parameters for any thermoplastic composite material combination. Thirdly, displacement control is used in the welding process to ensure consistent quality of the welded joints. According to this method, thermoplastic-composite flat coupons are individually welded in a single lap configuration. Mechanical testing of the welded coupons allows determining the apparent lap shear strength of the joints, which is one of the properties most commonly used to quantify the strength of thermoplastic composite welded joints.

A straightforward procedure for ultrasonic welding of thermoplastic composite coupons for basic mechanical testing is described. Key characteristics of this ultrasonic welding process are the use of flat energy directors for simplified process preparation and the use of process data for the fast definition of optimum processing conditions.

シングルラップせん断試験を経て溶接継手の機械的特性評価のための熱可塑性コンポジットクーポンの超音波溶接

This paper presents a novel straightforward method for ultrasonic welding of thermoplastic-composite coupons in optimum processing conditions. The ...

Fiber Optic Distributed Sensors for High-resolution Temperature Field Mapping

The reliability of computational fluid dynamics (CFD) codes is checked by comparing simulations with experimental data. A typical data set consists chiefly of velocity and temperature readings, both ideally having high spatial and temporal resolution to facilitate rigorous code validation. While high resolution velocity data is readily obtained through optical measurement techniques such as particle image velocimetry, it has proven difficult to obtain temperature data with similar resolution. Traditional sensors such as thermocouples cannot fill this role, but the recent development of distributed sensing based on Rayleigh scattering and swept-wave interferometry offers resolution suitable for CFD code validation work. Thousands of temperature measurements can be generated along a single thin optical fiber at hundreds of Hertz. Sensors function over large temperature ranges and within opaque fluids where optical techniques are unsuitable. But this type of sensor is sensitive to strain and humidity as well as temperature and so accuracy is affected by handling, vibration, and shifts in relative humidity. Such behavior is quite unlike traditional sensors and so unconventional installation and operating procedures are necessary to ensure accurate measurements. This paper demonstrates implementation of a Rayleigh scattering-type distributed temperature sensor in a thermal mixing experiment involving two air jets at 25 and 45 &#176;C. We present criteria to guide selection of optical fiber for the sensor and describe installation setup for a jet mixing experiment. We illustrate sensor baselining, which links readings to an absolute temperature standard, and discuss practical issues such as errors due to flow-induced vibration. This material can aid those interested in temperature measurements having high data density and bandwidth for fluid dynamics experiments and similar applications. We highlight pitfalls specific to these sensors for consideration in experiment design and operation.

We demonstrate use of a fiber optic distributed sensor for mapping the temperature field of mixing air jets. The Rayleigh scattering-based sensor generates thousands of data points along a single fiber to provide exceptional spatial resolution that is unattainable with traditional sensors such as thermocouples.

高分解能温度フィールドマッピングのための光ファイバの分散センサ

The reliability of computational fluid dynamics (CFD) codes is checked by comparing simulations with experimental data. A typical data set consists ...

Advanced Compositional Analysis of Nanoparticle-polymer Composites Using Direct Fluorescence Imaging

The fabrication of polymer-nanoparticle composites is extremely important in the development of many functional materials. Identifying the precise composition of these materials is essential, especially in the design of surface catalysts, where the surface concentration of the active component determines the activity of the material. Antimicrobial materials which utilize nanoparticles are a particular focus of this technology. Recently swell encapsulation has emerged as a technique for inserting antimicrobial nanoparticles into a host polymer matrix. Swell encapsulation provides the advantage of localizing the incorporation to the external surfaces of materials, which act as the active sites of these materials. However, quantification of this nanoparticle uptake is challenging. Previous studies explore the link between antimicrobial activity and surface concentration of the active component, but this is not directly visualized. Here we show a reliable method to monitor the incorporation of nanoparticles into a polymer host matrix via swell encapsulation. We show that the surface concentration of CdSe/ZnS nanoparticles can be accurately visualized through cross-sectional fluorescence imaging. Using this method, we can quantify the uptake of nanoparticles via swell encapsulation and measure the surface concentration of encapsulated particles, which is key in optimizing the activity of functional materials.

Here we present a reliable method to monitor the incorporation of nanoparticles into a polymer host matrix via swell encapsulation. We show that the surface concentration of cadmium selenide quantum dots can be accurately visualized through cross-sectional fluorescence imaging.

直接蛍光イメージングを用いたナノ粒子 - ポリマー複合材料の高度な組成分析

The fabrication of polymer-nanoparticle composites is extremely important in the development of many functional materials. Identifying the precise ...

High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia (YSZ) Scaffolds by In Situ Carbon Templating Xerogels

We demonstrate a method for the high temperature fabrication of porous, nanostructured yttria-stabilized-zirconia (YSZ, 8 mol% yttria - 92 mol% zirconia) scaffolds with tunable specific surface areas up to 80 m2&#183;g-1. An aqueous solution of a zirconium salt, yttrium salt, and glucose is mixed with propylene oxide (PO) to form a gel. The gel is dried under ambient conditions to form a xerogel. The xerogel is pressed into pellets and then sintered in an argon atmosphere. During sintering, a YSZ ceramic phase forms and the organic components decompose, leaving behind amorphous carbon. The carbon formed in situ serves as a hard template, preserving a high surface area YSZ nanomorphology at sintering temperature. The carbon is subsequently removed by oxidation in air at low temperature, resulting in a porous, nanostructured YSZ scaffold. The concentration of the carbon template and the final scaffold surface area can be systematically tuned by varying the glucose concentration in the gel synthesis. The carbon template concentration was quantified using thermogravimetric analysis (TGA), the surface area and pore size distribution was determined by physical adsorption measurements, and the morphology was characterized using scanning electron microscopy (SEM). Phase purity and crystallite size was determined using X-ray diffraction (XRD). This fabrication approach provides a novel, flexible platform for realizing unprecedented scaffold surface areas and nanomorphologies for ceramic-based electrochemical energy conversion applications, e.g. solid oxide fuel cell (SOFC) electrodes.

High Temperature Fabrication of Nanostructured Yttria-Stabilized-Zirconia YSZ Scaffolds by In Situ Carbon Templating Xerogels

A protocol for fabricating porous, nanostructured yttria-stabilized-zirconia (YSZ) scaffolds at temperatures between 1,000 &#176;C and 1,400 &#176;C is presented.

によってナノ構造イットリア安定化ジルコニア（YSZ）足場の高温製作<em&gt;その場での</em&gt;カーボンテンプレート化キセロゲル

We demonstrate a method for the high temperature fabrication of porous, nanostructured yttria-stabilized-zirconia (YSZ, 8 mol% yttria - 92 mol% zirconia) ...