Construction of a Bismuthene/CsPbBr₃ Quantum Dot S-Scheme Heterojunction and Enhanced Photocatalytic CO₂ Reduction

Abstract

The CO2 photoreduction process is becoming a promising strategy to solve the energy shortage problem and global warming in recent years. How to promote the separation of photoinduced carriers has attracted attention for the improvement of photocatalytic CO2 reduction. In the present work, an S-scheme heterojunction of Bismuthene/CsPbBr3 quantum dots (Bismuthene/CsPbBr3 QDs) is constructed as the photocatalyst for CO2 conversion. As a result, Bismuthene/CsPbBr3 QDs exhibit an optimal CH4 evolution rate of 43.1 μmol h–1 g–1 with 84.53% selectivity over CH4 under ultraviolet–vis light (UV–vis) irradiation. Construction of the S-scheme heterojunction with a narrow band gap semiconductor is the main factor for improving the photocatalytic performance, as the S-scheme heterojunction can suppress the recombination of photoinduced carriers and retain redox ability. The narrow band gap semiconductor Bismuthene can enhance light absorption abilities. This work probably provides some insights for the designing of heterojunction photocatalysts and the improvement of photocatalytic performance.

Lead-Free Halide Perovskite Cs2AgBiBr6/Bismuthene Composites for Improved CH4 Production in Photocatalytic CO2 Reduction

“…The almost transparent regions on the micrographs suggest that ultrathin nanostructures were achieved. Darker color regions can be ascribed to the crumpling and stacking of bismuthene nanosheets . The HRTEM image of bismuthene is displayed in Figure b, where clear lattice fringes can be observed, and the spacing of the measured fringes is 0.32 nm, assigned to the (102) plane of the hexagonal crystal phase of bismuthene.…”

“…1.46 and 1.26 eV for Bi(0) 4f 5/2 and Bi(0) 4f 7/2 in DP/Bi2, respectively, indicating interfacial interactions between the Bi atoms in bismuthene and the DP nanoparticles. 34 Figure 6b shows the O 1s spectra of DP and DP/Bi composites. The O 1s spectrum of DP is deconvoluted into two peaks centered at 532.32 and 533.84 eV attributed to the residual organic C−O and C�O bonds, respectively, from the capping oleic acid used in the synthesis process.…”

Constructing an all zero-dimensional CsPbBr3/CdSe heterojunction for highly efficient photocatalytic CO2reduction

“…S5†), which were consistent with previous reports. 53,54 The valence band maximum (VBM) potential was obtained by analyzing the photoelectron spectroscopy characterization (Fig. S6†).…”

Amino Acid-Assisted Preparation of Homogeneous PbS/CsPbBr3 Nanocomposites for Enhanced Photoelectrocatalytic CO2 Reduction

“…As a class of new emerged semiconductors, all-inorganic lead halide perovskites (LHPs) CsPbX 3 have received extensive interest in optoelectronic applications because of their attractive photoelectronic properties such as defect-tolerant band structure, high photoluminescence efficiency, wide absorption range, and tunable band gap expanding the whole visible range. − Such unique features indicate that LHPs can also function as an excellent photosensitizer for CO 2 reduction, water splitting, and degradation of organic species. − However, the fast radiative recombination of photogenerated carriers and poor structural stability of LHPs severely hinder their catalytic performance. ,, Designing composited cocatalysts has been demonstrated to be an effective approach to promote the charge separation and enhance photocatalytic activity. ,,− Although some combinations of metal halide perovskites with metal oxide, metal organic framework, and graphene have been reported, ,− the photocatalytic efficiency is still limited due to their weak intermolecular van der Waals interaction and heterogeneous distribution. Nanostructured metal sulfides have been demonstrated to be good candidates for photocatalytic CO 2 reduction due to their carriers with small effective mass, wide photoresponsive range, and good catalytic activity of surface/edge sites. − Among these catalysts, PbS shows great potential to enhance the catalytic performance of CsPbBr 3 because of the small lattice mismatch, better stability, and the catalytic activity toward CO 2 . − However, PbS/CsPbBr 3 nanocomposites with improved catalytic performance of CRR have rarely been achieved.…”