Controlled Growth of CdS Nanostep Structured Arrays to Improve Photoelectrochemical Performance

Abstract

CdS nanostep-structured arrays were grown on F-doped tin oxide-coated glasses using a two-step hydrothermal method. The CdS arrays consisted of a straight rod acting as backbone and a nanostep-structured morphology on the surface. The morphology of the samples can be tuned by varying the reaction parameters. The phase purity, morphology, and structure of the CdS nanostep-structured arrays were characterized by X-ray diffraction and field emission scanning electron microscopy. The light and photoelectrochemical properties of the samples were estimated by a UV-Vis absorption spectrum and photoelectrochemical cells. The experimental results confirmed that the special nanostep structure is crucial for the remarkable enhancement of the photoelectrochemical performance. Compared with CdS rod arrays, the CdS nanostep-structured arrays showed increased absorption ability and dramatically improved photocurrent and energy conversion efficiency. This work may provide a new approach for improving the properties of photoelectrodes in the future.

Preparation of Highly Active Catalyst CoS2/CdS and Its Mechanism of Photocatalytic H2 Evolution

“…X-ray diffraction (XRD) was adopted to analyze the structures of different samples. Figure 1 shows that the peaks are identified as those of cubic CdS (PDF#10-0454), 47 hexagonal CdS (PDF#77-2306), 48 and the cubic phase CoS 2 (PDF#41-1471), 27 demonstrating that pure cubic phase CdS (c-CdS), hexagonal phase CdS (h-CdS), and cubic phase CoS 2 were prepared.…”

Plasmonic Solar Energy Harvesting by ZnO Nanostructures and Their Composite Interfaces: A Review on Fundamentals, Recent Advances, and Applications

“…It increases visible light absorption for PEC-WS as CdS has an appropriate band gap of 2.43 eV to absorb visible light and ZnO has a wide band gap to allow the visible light through ZnO shell. [120][121][122] When coupling CdS with ZnO, the typical type II mode is achieved because of their staggering bandgap structures as both the conduction band maximum and valance band maximum of CdS have higher potentials than those of ZnO which could not only effectively accelerate the photogenerated carrier transfer from CdS to ZnO but also hugely suppress the internal charge recombination. [120,123] CdS has been widely explored for its direct bandgap (2.43 eV) which matches well with the spectrum of sunlight and sufficient conduction band potential for the reduction of H þ to H 2 in an acidic environment.…”

“…[120][121][122] When coupling CdS with ZnO, the typical type II mode is achieved because of their staggering bandgap structures as both the conduction band maximum and valance band maximum of CdS have higher potentials than those of ZnO which could not only effectively accelerate the photogenerated carrier transfer from CdS to ZnO but also hugely suppress the internal charge recombination. [120,123] CdS has been widely explored for its direct bandgap (2.43 eV) which matches well with the spectrum of sunlight and sufficient conduction band potential for the reduction of H þ to H 2 in an acidic environment. However, rapid recombination of photogenerated electron and hole pairs in CdS causes a very poor H 2 yield.…”

Novel approaches to energize microbial biocatalysts

“…For instance, spherical nanoparticles are more efficacious relative to other morphologies given the low surface area‐to‐volume ratio of a sphere, which contributes to maximize their biocompatibility and interactions with the cell membrane and, hence, foster electron transference to enzymatic mediators and metabolic charge carriers (Deng et al, 2020 ; Sakimoto et al, 2016 ). Although these features are difficult to optimize through the standard chemical synthesis of SNs, they could be approached through their biological production (Cheng et al, 2018 ; Jiang et al, 2020 ). It would be interesting also to biosynthesize other types of SNs endowed with new optimal properties as photocatalysts.…”