3D-Branched ZnO/CdS Nanowire Arrays for Solar Water Splitting and the Service Safety Research

• Published in: Advanced energy materials Vol. 6; no. 3; pp. np - n/a
• Main Authors: Bai, Zhiming, Yan, Xiaoqin, Li, Yong, Kang, Zhuo, Cao, Shiyao, Zhang, Yue
• Format: Journal Article
• Language: English
• Published: Weinheim Blackwell Publishing Ltd 01.02.2016; Wiley Subscription Services, Inc
• Subjects: 3D structures; Arrays; Broadband; Cadmium sulfide; Catalytic activity; Chemical synthesis; Deposition; Nanoparticles; Nanowires; photoanodes; Photocatalysis; Photovoltaic cells; Semiconductors; service safety; Solar energy; Three dimensional; Three dimensional composites; Titanium dioxide; Titanium oxides; Trapping; Water splitting; Zinc oxide
• ISSN: 1614-6832; 1614-6840
• DOI: 10.1002/aenm.201501459

Modulation of broadband light trapping through assembly of 3D structures and modification with narrow band‐gap semiconductors provide an effective way to improve the photoelectrochemical (PEC) performance. Here, 3D‐branched ZnO nanowire arrays (NWAs) modified with cadmium sulfide (CdS) nanoparticles are designed and synthesized via solution chemical routes. The 3D‐branched ZnO NWA–CdS nanoparticle photoanodes show an excellent PEC performance in UV and visible region and the maximum photo‐to‐hydrogen conversion efficiency reaches to 3.1%. The high performance of 3D‐branched ZnO NWA–CdS composites is mainly attributed to the excellent carrier collection capability and high light‐trapping ability of 3D‐branched ZnO NWAs as well as the excellent photocatalytic activity of CdS nanoparticles in the visible region. In addition, the photocorrosion mechanism of 3D‐branched ZnO NWA–CdS photoanodes is systematically investigated, and a protective TiO2 layer is deposited onto the photoanodes to elevate the PEC stability. The results benefit a deeper understanding of the role of 3D‐branched structures decorated with narrow band‐gap semiconductors in solar water splitting. The photoelectrochemical (PEC) performance of 3D ZnO nanowire arrays (NWAs)–Cadmium sulfide (CdS) is greatly affected by the CdS deposition cycle number, and the 50‐deposition cycle sample shows the highest conversion efficiency of 3.1%. CdS nanoparticles expand the photocatalytic activity of 3D ZnO NWA–CdS in the visible range. The TiO2 layer greatly reduces the photocorrosion reaction and enhances the PEC stability.