Wafer-Level Artificial Photosynthesis for CO2 Reduction into CH4 and CO Using GaN Nanowires

详细信息    查看全文

• 作者：Bandar AlOtaibi ; Shizhao Fan ; Defa Wang ; Jinhua Ye ; Zetian Mi
• 刊名：ACS Catalysis
• 出版年：2015
• 出版时间：September 4, 2015
• 年：2015
• 卷：5
• 期：9
• 页码：5342-5348
• 全文大小：401K
• ISSN：2155-5435

文摘

We report on the first demonstration of high-conversion-rate photochemical reduction of carbon dioxide (CO₂) on gallium nitride (GaN) nanowire arrays into methane (CH₄) and carbon monoxide (CO). It was observed that the reduction of CO₂ to CO dominates on as-grown GaN nanowires under ultraviolet light irradiation. However, the production of CH₄ is significantly increased by using the Rh/Cr₂O₃ core/shell cocatalyst, with an average rate of 鈭?.5 渭mol g_cat^鈥? h^鈥? in 24 h. In this process, the rate of CO₂ to CO conversion is suppressed by nearly an order of magnitude. The rate of photoreduction of CO₂ to CH₄ can be further enhanced and can reach 鈭?4.8 渭mol g_cat^鈥? h^鈥? by promoting Pt nanoparticles on the lateral m-plane surfaces of GaN nanowires, which is nearly an order of magnitude higher than that measured on as-grown GaN nanowire arrays. This work establishes the potential use of metal-nitride nanowire arrays as a highly efficient photocatalyst for the direct photoreduction of CO₂ into chemical fuels. It also reveals the potential of engineered core/shell cocatalysts in improving the selectivity toward more valuable fuels.