【公開日：2023.07.28】【最終更新日：2023.05.12】
課題データ / Project Data
課題番号 / Project Issue Number
22HK0095
利用課題名 / Title
Fabricating NiO photocathode under strong coupling for photoreduction reaction
利用した実施機関 / Support Institute
北海道大学 / Hokkaido Univ.
機関外・機関内の利用 / External or Internal Use
外部利用/External Use
技術領域 / Technology Area
【横断技術領域 / Cross-Technology Area】（主 / Main）加工・デバイスプロセス/Nanofabrication（副 / Sub）計測・分析/Advanced Characterization
【重要技術領域 / Important Technology Area】（主 / Main）量子・電子制御により革新的な機能を発現するマテリアル/Materials using quantum and electronic control to perform innovative functions（副 / Sub）-
キーワード / Keywords
電子顕微鏡/Electron microscopy,スパッタリング/Sputtering,蒸着・成膜/Evaporation and Deposition,ALD,フォトニクス/ Photonics
利用者と利用形態 / User and Support Type
利用者名（課題申請者）/ User Name (Project Applicant)
Zhao Shuo
所属名 / Affiliation
Harbin Institute of Technology
共同利用者氏名 / Names of Collaborators in Other Institutes Than Hub and Spoke Institutes
ARIM実施機関支援担当者 / Names of Collaborators in The Hub and Spoke Institutes
三澤 弘明,松尾 保孝,石 旭
利用形態 / Support Type
（主 / Main）機器利用/Equipment Utilization（副 / Sub）-
利用した主な設備 / Equipment Used in This Project
HK-611：多元スパッタ装置
HK-618：プラズマ原子層堆積装置
HK-607：EB蒸着装置
HK-616：原子層堆積装置
HK-404：超高分解能電界放出形走査電子顕微鏡
報告書データ / Report
概要（目的・用途・実施内容）/ Abstract (Aim, Use Applications and Contents)
In this study, we fabricate nickel oxide (NiO) thin-film photocathodes under the modal strong coupling conditions to enhance the photochemical reaction efficiency, especially the carbon dioxide reduction reaction. Photoelectrode under modal strong coupling conditions was demonstrated to broaden the harvesting spectrum region, and even improve the internal quantum efficiency of chemical reactions.[1,2]Copper is one of the most attractive metals to synthesize hydrocarbons from CO2 because of its optimal binding ability with CO2 and the reaction intermediates.[3] Herein, we investigate a plasmonic photocathode system composed of Cu-Au alloy nanoparticles (CuAu-NPs)/NiO/Pt film, which utilizes the advantage of the coupling between the localized surface plasmon resonance (LSPR) and the Fabry-Pérot (FP) cavity for light absorption enhancement.
実験 / Experimental
The CuAu-NPs/NiO/Pt structure was fabricated on a silica glass substrate with dimensions of 10×10×1.0 mm3. The silica substrates were cleaned with acetone, methanol, and deionized water in an ultrasonic bath for 5 min and dried by nitrogen flow. A layer of Pt-film (~100 nm) was deposited onto a silica glass substrate by a sputtering system (ULVAC, QAM-4-STS) with a 2-nm Ti adhesion layer. A 45-nm NiO film was deposited by sputtering in oxygen on the Pt-film at room temperature. Cu and Au thin film were sequentially evaporated by an electron-beam evaporator (EIKO, EB-580) at a deposition rate of 0.1 Å/s. Finally, the samples were annealed in a nitrogen atmosphere at 300°C for 2 h, and CuAu-NPs appeared on the NiO film surfaces.
結果と考察 / Results and Discussion
Figure 1 (a) shows the surface morphology of NiO film deposited on 100-nm Pt film. A smooth NiO surface was identified. Figure 1 (b) shows the XRD spectrum of 45-nm NiO/Pt-film. Characteristic NiO crystal peaks were observed, indicating a good crystallinity of NiO fabricated by the sputtering in oxygen. Before Cu-Au alloy nanoparticle deposition, we measured the photoelectrochemical properties of the NiO/Pt film. Figure 2(a) shows the C-V curve of NiO/Pt-film as fabricated. The flat-band potential was also measured by Mott-Schottky plot, as shown in Figure 2(c). The flat-band potential was calculated to be 0.433 V vs. SCE. A post-annealing treatment was performed to improve the photoelectrochemical properties of the NiO/Pt film. Figure 2(c) shows the C-V curve of NiO/Pt film after annealing at 500 ℃. It is noted that the flat band potential was increased to 1.132 V vs. SCE after annealing which is corresponding to the reference value. Based on the fabricated NiO/Pt film samples, we will deposit CuAu NPs on NiO/Pt film and apply them for CO2 reduction by measuring the photocurrent conversion efficiency and the reaction products.
図・表・数式 / Figures, Tables and Equations
Figure 1. (a) SEM image of NiO surface. (b) XRD spectrum of NiO thin-film deposited on 100-nm Pt film.
Figure 2. C-V curves and mott-schottky curve of as-deposited NiO film (a,c) and annealed NiO film (b,d).
その他・特記事項（参考文献・謝辞等） / Remarks(References and Acknowledgements)
References[1] Shi, X.; Ueno, K.; Oshikiri, T.; Sun, Q.; Sasaki, K.; Misawa, H., Nat. Nanotechnol., 2018, 13, 953-958.[2] Suganami, Y.; Oshikiri, T.; Shi, X.; Misawa, H., Angew. Chem. Int. Ed., 2021, 60, 18438-18442.[3] Ross, M.B., De Luna, P., Li, Y. et al. Nat. Catal., 2019, 2, 648-658.
成果発表・成果利用 / Publication and Patents
論文・プロシーディング（DOIのあるもの） / DOI (Publication and Proceedings)
口頭発表、ポスター発表および、その他の論文 / Oral Presentations etc.
特許 / Patents
特許出願件数 / Number of Patent Applications：0件
特許登録件数 / Number of Registered Patents：0件