P-type β-Ni(OH)2 nanoparticles sensitize CdS nanorod array photoanode to prolong charge carrier lifetime and highly improve bias-free visible-light-driven H2 evaluation

Here, we report a novel beta-Ni(OH)(2)@CdS shell-core nanorod array (NRA) photoanode with prolonged lifetime for highly efficient H-2 generation. The fabricated photoanode shows drastically enhanced ability to generate H-2 from water splitting under bias-free visible light irradiation. The H-2 production rate of beta-Ni(OH)(2)@CdS NRA photoelectrode reaches 762.5 mu mol h(-1), 8 times as high as that of pure CdS NRA photoelectrode. In addition, the constructed beta-Ni(OH)(2)@CdS shell-core NRA photoanode exhibits an outstanding stability. Mott-Schottky measurements clearly demonstrate that both p-n junction and type-II band alignment are established at beta-Ni(OH)(2) and CdS interface. This unique band structure is highly favorable for the transfer and separation of charge carriers, significantly suppressing charge recombination, as confirmed by photoluminescence emission study. Moreover, the measurements of electrochemical spectroscopy undoubtedly confirm that the lifetime of charge carriers within this unique band structure is significantly prolonged, leading to drastically enhanced photo-electrochemical water splitting for H-2 generation.