posted on 2022-10-05, 19:33authored byXin Li, Linyang Chen, Ying Li, Likui Wang, Haijun Wang, Jingguo Yang, Hongyan Miao, Gang Shi
Photoelectrochemical water splitting is one of the most
promising
means of hydrogen production. Micro-/nanostructured silicon (Si) is
beneficial to reduce the light reflection on the electrode surface
to enhance the utilization efficiency of solar energy. However, the
multiple reflection of light in the micro-/nanostructure on the Si
surface will increase the parasitic light absorption by cocatalysts.
In this work, the 3D black Si with micro-pyramids and nanopores was
obtained, which anti-reflective structure can improve light absorption.
Meanwhile, the non-uniform deposition of N-CoP3 on 3D black
Si can be induced by the micro-pyramid structure, minimizing the parasitic
light absorption of N-CoP3 and improving the photoelectrochemical
performance of the 3D black Si/N-CoP3 photoelectrode. The
designed photoelectrode can achieve a high onset potential of 0.315
V versus RHE and a photocurrent density of −21.8
mA cm–2 at 0 V versus RHE. Meanwhile,
the 3D black Si/N-CoP3 exhibits >10 h stability under
simulated
100 mW cm–2 (1 sun) with an AM 1.5G filter in 0.5
M H2SO4 at 0 V versus Ag/AgCl.