Three-dimensional hierarchical PANI/Bi2S3 nanoflowers heterojunction for enhanced photoelectrochemical water splitting

The fabrication of the semiconductor photoanode with good chemical stability, sufficient light harvesting ability, and fast charge carrier separation and transportation capability is crucial for efficient photoelectrochemical (PEC) water splitting. Herein, we designed the nanocomposite based photoelectrode which is integrated by hydrothermally grown 3D hierarchical nanoflowers (NFs) of bismuth sulfide (Bi2S3) and conducting polymer polyaniline (PANI). The as-fabricated PANI/Bi2S3 photoanode has demonstrated much enhanced photocurrent density (similar to 6.95 mA/cm(2) at 0.8 V vs. NHE), which is similar to 5 fold higher in comparison to Bi(2)S(3 )photoanode (similar to 1.30 mA/cm(2) at 0.8 V vs. NHE). Also, the PANI/Bi(2)S(3 )photoanode has exhibited profoundly increased charge separation and injection efficiency of similar to 78.31% and similar to 90.18%, respectively. Furthermore, similar to 3 fold increased incident photon-to-current conversion efficiency (IPCE) value is achieved by PANI/Bi(2)S(3 )as compared to the Bi(2)S(3 )photoanode. The rational design of hierarchical semiconductor heterojunction, improved visible light absorption, efficient separation of photogenerated charge carriers, and faster charge transport properties altogether account for the enhanced PEC performance of the fabricated PANI/Bi(2)S(3 )photoanode. A possible schematic model for the significantly enhanced activity of the PANI/Bi2S3 photoanode for solar light induced PEC water splitting has also been explicated. These findings would provide new opportunities for understanding, exploration, and advancement of different other novel 3D hierarchical nanostructures based systems in the area of energy conversion, harvesting, and storage in the future. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The study presents a nanocomposite photoelectrode of PANI/Bi2S3 with enhanced photocurrent density and charge separation efficiency. The improved PEC performance of PANI/Bi2S3 is attributed to its hierarchical semiconductor heterojunction, visible light absorption, and efficient charge transport properties.