Isopropanol-assisted synthesis of highly stable MAPbBr₃/p-g-C₃N₄ intergrowth composite photocatalysts and their interfacial charge carrier dynamics

Abstract

Two phase photocatalysts can be intergrown with each other, resulting in superior photocatalytic properties. Herein, methylamine lead bromide (MAPbBr 3 ) wrapped/entrapped protonated graphitic carbon nitride (p-g-C 3 N 4 ) intergrowth microcrystals were fabricated by mixing a pervoskite precursor with p-g-C 3 N 4 colloidal sol. A highly stable isopropanol (IPA) solvent based photocatalytic system for dye degradation was demonstrated. The composite with an optimal p-g-C 3 N 4 mass percentage of 3.3 wt% (denoted as MAPbBr 3 /p-g-C 3 N 4 -1.0 mg) exhibited the highest photocatalytic degradation of malachite green (99.8%) within 10 min under visible light, which was 5.3-fold and 16-fold greater than that exhibited by its constituents separately. The strong chemical interaction and fundamental photophysical processes in MAPbBr 3 /p-g-C 3 N 4 were systematically evaluated by spectroscopic and electrochemical techniques, confirming the effective separation of photogenerated electron-hole pairs and faster interfacial charge transfer behavior. Furthermore, active superoxide radicals (O 2 c À ) played a vital role in the catalytic reaction, because of the significant photoinduced electron transfer rate (k et ) in the inverted type-I core/shell MAPbBr 3 /p-g-C 3 N 4 band configuration structure. In addition, MAPbBr 3 /p-g-C 3 N 4 has good cycling stability for 10 cycles and versatility for other cationic (RhB) and anionic (MO) dye pollutants, indicating the great potential for solar energy conversion into chemical energy.

Metal Halide Perovskite/2D Material Heterostructures: Syntheses and Applications

“…constructed heterostructures based on MAPbBr 3 microcrystals and p‐g‐C 3 N 4 for the malachite green (MG) degradation. [ 166 ] Different from the work of Pu et al., [ 66b ] in this work, the MAPbBr 3 /p‐g‐C 3 N 4 intergrowth composites formed an inverted type‐I core/shell structure (Figure 18e). As a result, both electrons and holes will transfer from the p‐g‐C 3 N 4 core to the MAPbBr 3 shell, thus efficiently promote the redox reaction.…”

“…Because MHP/2D material heterostructures are incompatible with aqueous media, solvents with mild polarity such as ethyl acetate, isopropanol, and toluene are commonly chosen for photocatalytic CO 2 reduction and organic compound degradation to avoid the degradation of MHPs. [ 35b,69a,166 ] For photocatalytic H 2 evolution, a saturated perovskite solution containing hydroiodic acid or hydrobromic acid is required to protect MHPs from decomposition, which is quite material‐consuming. Besides, the acidic solution condition may cause serious environmental problems.…”

“…Second, MHP/2D material heterostructures suffer from unsatisfactory long‐term stability due to the sensitivity of MHPs to moisture, light and heat. [ 166 ] The stability of MHPs can be greatly enhanced under the protection of metal oxides, organic molecules, and polymers. [ 169c,d ] For example, silica‐encapsulated perovskites can maintain the PL intensity even in an acidic aqueous solution for 50 days.…”

Synthesis and Characterization of Heterostructure Pd/Bi2WO6 Nanocomposites with Enhanced Properties of Visible-Light-Driven Photocatalyst

“…During photodegradation of RhB solutions containing 10% Pd/Bi 2 WO 6 nanocomposites under visible light irradiation, isopropanol (IPA), benzoquinone (BQ) and ethylenediaminetetraacetic acid disodium salt (EDTA-2Na) were also added for scavenging hydroxyl radical ( • OH), superoxide radical ( • O 2 − ) and photogenerated hole (h + ), respectively [32][33][34][35]. The photodegradation of RhB (Fig.…”

Recent Progress in Engineering Metal Halide Perovskites for Efficient Visible‐Light‐Driven Photocatalysis

“…Inspired by these pioneering works, various materials have been further employed for incorporation with MHPs to improve the activity and stability in aqueous solutions, such as black phosphorus (BP)/MAPbI 3 , g‐C 3 N 4 /MAPbBr 3 , and multicomponent CsPbBr 3 /Ru−TiO 2 heterojunctions. To date, the highest H 2 generation rate of 7.3 mmol g −1 h −1 was achieved over BP/MAPbI 3 hybrid materials.…”