Anchoring lead-free halide Cs3Bi2I9 perovskite on UV100–TiO2 for enhanced photocatalytic performance

Abstract

Halide perovskites have shown great potential in photocatalytic applications. In order to enhance the charge transportation efficiency, the chemical stability, and the light absorption ability, we anchored a lead-free halide perovskite (Cs3Bi2I9) on UV100-TiO2 nanoparticles to build a visiblelight active photocatalysts. The as-prepared material exhibited excellent stability and a remarkable yield for photocatalytic oxidation of methanol to formaldehyde under visible light irradiation. The photocatalyst was characterized using X-ray diffraction, scanning electron microscopy, energydispersive X-ray spectroscopy, Transmission electron microscopy, X-ray photoelectron spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy, Brunauer-Emmett-Teller surface area measurement, and photoelectrochemical properties. The analyses confirmed a remarkable improvement of visible-light absorption, a favorable decrease in the recombination of photoinduced charge carriers, and a suitable bandgap for visible-light photocatalytic applications. 2Recycle experiments showed that the composites still presented significant photocatalytic activity after three successive cycles. A possible underlying mechanism of the composite accounting for the enhanced photocatalytic activity under visible light irradiation was proposed.Our study aims to open new possibilities of using lead-free halide perovskites for photocatalytic applications.

Pb-Free Cs3Bi2I9 Perovskite as a Visible-Light-Active Photocatalyst for Organic Pollutant Degradation

“…The obtained lattice parameters are a = 8.404 Å, b = 8.404 Å, and c = 21.183 Å, which are in good agreement with previous studies [31,37]. More details are presented in our previous report [54]. The morphology of the Cs3Bi2I9 powder was investigated by means of transmission electron microscopy (TEM and SEM).…”

“…Reference source not found.a and b) of Cs3Bi2I9 depict that the particles exhibited hexagonal shapes with an average size in the order of a hundred nanometers. From the SEM images, the Cs3Bi2I9 powder shows a typical 3D structure of particles with rough surfaces; further details are shown in our previous report [54]. The growth of well-defined crystals is important to highlight, because a high crystallinity, which is confirmed by the XRD as well, is one important factor for the efficient separation and transport of photogenerated charge carriers [55].…”

“…The XPS analysis further results in atomic percentages (I: 51.4%, Cs: 22.4%, and Bi: 9.9%) that agree well with the percentages obtained by the EDX analysis. Further details are presented in our previous report [54]. The BET surface area of the Cs3Bi2I9 powder was measured based on nitrogen adsorption to be 5.6 m 2 g −1 .…”

“…Further details are presented in our previous report [54]. The BET surface area of the Cs3Bi2I9 powder was measured based on nitrogen adsorption to be 5.6 m 2 g −1 .…”

In Situ Construction of Lead‐Free Perovskite Direct Z‐Scheme Heterojunction Cs3Bi2I9/Bi2WO6 for Efficient Photocatalysis of CO2 Reduction

“…[ 21,22 ] Accordingly, multifarious lead‐free halide perovskites have been exploited and used as catalysts in the field of photocatalysis. [ 23–34 ] Among these lead‐free perovskites, bismuth‐based halide perovskites have received increasing attention owing to their low toxicity and high stability compared with LHPs. In particular, all‐inorganic cesium bismuth halide (Cs 3 Bi 2 X 9 , X = Br or I) perovskite nanocrystals have been actively exploited as photocatalysts for CO 2 reduction, [ 28 ] H 2 evolution, [ 32 ] organic synthesis, [ 25 ] and organic pollutant degradation.…”