CdS nanoflakes decorated by Ni( OH ) ₂ nanoparticles for enhanced photocatalytic hydrogen production

Abstract

P-type Ni(OH) 2 has been combined with n-type CdS nanorods and nanocrystals for enhanced photocatalytic property due to the p-n junction. Though CdS nanosheets exhibit fast charge transfer and large superficial area, the decoration of Ni(OH) 2 was rarely reported up to now. In this work, the photodeposition of Ni(OH) 2 nanoparticles on CdS ultrathin nanoflakes was established for efficient photocatalytic H 2 generation. By changing the irradiation time of CdS, the reaction between Ni 2+ and OH À can be controlled for different loading density of Ni(OH) 2 . As the loading density-dependent morphology, light absorption, carrier separation and transfer were systematically studied for the composites, an obvious band gap narrowing from 2.28 to 2.08 eV was revealed, and the carrier separation and transfer between the CdS nanoflakes and Ni(OH) 2 nanoparticles have been enhanced for the composites with deposition time of 3 minutes. These together with the alignment of type "II" bands and the high specific surface area of the flakes and nanoparticles, lead to an optimum H 2 generation of 20.14 mmol/g/h, nearly three times of pure CdS (7.97 mmol/g/h). Such a study not only provides a deposition method of Ni(OH) 2 , but also sheds light on the enhancement strategy for photocatalytic property by controlling the microstructure and aligning the hetero-structured bands.

NiAl‐LDH In‐Situ Derived Ni2P and ZnCdS Nanoparticles Ingeniously Constructed S‐Scheme Heterojunction for Photocatalytic Hydrogen Evolution

“…The hydrogen production efficiency of the catalyst is improved. In the meantime, the self-supporting three-dimensional nanostructure (NiÀ P) enhances the specific surface area of Zn 0.5 Cd 0.5 S. [28] On this basis, we use NiAl-LDH-P containing Ni 2 P as the matrix and carry Zn 0.5 Cd 0.5 S to obtain a Zn 0.5 Cd 0.5 S/NiAl-LDH-P composite photocatalyst, which has a better and more stable Hydrogen evolution rate. At the same time, Zn 0.5 Cd 0.5 S nanoparticles are adsorbed on NiAl-LDH-P to realize the formation of s-scheme heterojunction between NiAl-LDH-P and Zn 0.5 Cd 0.5 S, which broadens the energy band of composite materials and enhances visible light absorption scope.…”

Seed-Assisted Synthesis of Ni(OH)2 Nanosheets on InGaN Films as Photoelectrodes toward Solar-Driven Water Splitting

“…The flat band potential (V fb ) at the semiconductor/ electrolyte interface is determined by measuring the capacitance of the space charge layer in relation to the applied bias voltage. 26−28 29,30 This situation leads to formation of a p−n junction near the semiconductor/ electrolyte interface, resulting in increased band bending and a built-in electric field.…”

“…The typical V fb values for samples A–C were −0.9, −1.36, and −1.4 V, respectively. The higher V fb values observed in the Ni(OH) 2 -coated samples can be attributed to the inherent p-type nature of Ni(OH) 2 . , This situation leads to formation of a p–n junction near the semiconductor/electrolyte interface, resulting in increased band bending and a built-in electric field.…”

Preparation of TiO2/CdS/Ni(OH)2 Composite Photoanode for Nonsacrificial Photoelectrochemical Water Splitting

“…37,38 Qiu et al proved that p-type Ni(OH) 2 combined with n-type CdS nanorods exhibits good photocatalytic property. 39 Wang et al designed a novel three-dimensional CdS@Ni(OH) 2 nanorod array photoanode, which improved PEC water splitting performance. 40 Wang et al successfully prepared Ni(OH) 2 -TiO 2 −Cu 2 O ternary hybrid and improved the efficiency of photocatalytic hydrogen production.…”