Thermal replacement reaction: a novel route for synthesizing eco-friendly ZnO@γ-In₂Se₃hetero-nanostructures by replacing cadmium with indium and their photoelectrochemical and photocatalytic performances

Abstract

A novel route called thermal replacement reaction was demonstrated for synthesizing eco-friendly ZnO@γ-In2Se3 hetero-structural nanowires on FTO glass by replacing the element cadmium with indium for the first time. The indium layer was coated on the surface of the ZnO nanowires beforehand, then CdSe quantum dots were deposited onto the coated indium layer, and finally the CdSe quantum dots were converted to γ-In2Se3 quantum dots by annealing under vacuum at 350 °C for one hour. The prepared ZnO@γ-In2Se3 hetero-nanostructures exhibit stable photoelectrochemical properties that can be ascribed to the protection of the In2O3 layer between the ZnO nanowire and γ-In2Se3 quantum dots and better photocatalytic performance in the wide wavelength region from 400 nm to nearly 750 nm. This strategy for preparing the ZnO@γ-In2Se3 hetero-nanostructures not only enriches our understanding of the single replacement reaction where the active element cadmium can be replaced with indium, but also opens a new way for the in situ conversion of cadmium-based to eco-friendly indium-based nano-devices.

Multichannel Charge Transport of a BiVO4/(RGO/WO3)/W18O49 Three-Storey Anode for Greatly Enhanced Photoelectrochemical Efficiency

“…As for the type-II band alignment of electrode, a narrow-band-gap semiconductor material should be coupled to another wide-band-gap material with both lower conduction and valence band edges. Using a photoanode constructed by n-type semiconductors as example, electrons migrate from the photoexcited narrow- to wide-band-gap material under illumination for the H 2 evolution reaction, whereas holes accumulate at the interface between the electrolyte and narrow-band-gap material for the oxygen evolution reaction (OER), leading to efficient charge separation, retarded charge recombination, and thus improved photoconversion efficiency. , …”

Performance‐Enhancing Broadband and Flexible Photodetectors Based on Perovskite/ZnO‐Nanowire Hybrid Structures

“…For the photodetectors, the artificial devices that convert photons to electricity, light‐harvesting materials become the core component . With suitable electronic band structures and versatile physical features, inorganic semiconductor nanomaterials such as ZnO are considered as the critical building blocks for these advanced electronic and optoelectronic devices, including field effect transistors (FETs), nanolasers, solar cells, light‐emitting diodes, and high‐sensitivity photodetectors . In the last decades, photodetectors established on versatile ZnO nanostructures have already been realized with respect to the excellent photoconductive properties; however, these light sensors suffer a narrow spectral response range and poor transient response due to the constrains of optoelectronic transfer efficiency and light absorption ability, which significantly restrict their practical applications .…”

ZnFe2O4 Nanotapers: Slag Assistant-Growth and Enhanced Photoelectrochemical Efficiency

“…Most of the holes accumulated on the surface of the REO layers oxidize the S 2− ions to S 2 2− ions. The role of the sacrificial reagent in the electrolyte (SO 3 2− ) is to prevent a reverse reaction by reducing S 2 2− to S 2− [37]. For the branched structures, the large surface area can absorb abundant light irradiation and supply plenty of interfacial area with electrolyte for PEC reaction [38].…”