Photoactive anode of NiO/TiO_2 nanotube p-n junctions and application in photoassisted water electrolysis

摘要

The photoactive anode was fabricated by hydrothermal method using the ZnO nanorod array as the template. NiO nanoflakes were assembled on the TiO_2 tubular arrays to form p-n junction heterostrucutures on the Ni substrate. The water electrolysis was coupled with photocatalytic decomposition of water by irradiation of UV and UV-visible light on the modified Ni anode. Under UV and UV-visible light irradiation, the hydrogen evolution rates of the photoactive Ni anode modified by NiO/TiO_2 nanotube composites are 2.92 ml/h·cm~2 and 3.16 ml/h·cm~2 respectively, increased by 5.4% and 15% in comparison with that of the Ni anode modified by TiO_2 nanotube array and showed 152% and 172% improvement in comparison with that of sole Ni anode respectively.