任俊涛

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.