Phenyl-C61-butyric acid methyl ester (PCBM) nanoparticle mediated boasting of photoelectrochemical and photocatalytic properties of bismuth vanadate/lead sulphide (BiVO4/PbS) composite thin-film

This work delineates the fabrication and characterization of BiVO₄/PbS and BiVO₄/PCBM/PbS-based composite heterostructure for visible-light-driven applications, such as pollution remediation, photoelectrochemistry (PEC), and applied bias to photoelectrochemical hydrogen generation efficiency (ABPE). The heterostructured composite was synthesized by a combination of Spin coating (for bismuth vanadate - BiVO₄ thin film fabrication and PCBM deposition), and Successive Ionic Layer Absorption and Reaction -SILAR (for lead sulphide - PbS deposition) method and characterized using UV–visible Spectroscopy, time-resolved photoluminescence spectroscopy (TRPL), field emission scanning electron microscope (FESEM), X-ray diffraction (XRD), and photoelectrochemistry (PEC) analysis (PEC). The key benefit of incorporation of PCBM nanoparticles in BiVO₄/PCBM/PbS was realized through 1) ∼ 70 % improvement in the photocurrent density during electrochemistry analysis, 2) ∼ 2.3 times enhancement in ABPE, and 3) ∼ 43 % enhancements in ‘rate constant’ towards photocatalytic (methylene blue) degradation compared to BiVO₄/PbS. The work shows the benefits of the PCBM-conductive carbon-based electron transport layer as a bridge between two inorganic semiconductors (BiVO₄ and PbS) towards enhancing fast electron separation and transport at the interface during visible light irradiation.