In‐Situ Generated CsPbBr₃ Nanocrystals on O‐Defective WO₃ for Photocatalytic CO₂ Reduction

Abstract

Metal halide perovskite (MHP) nanocrystals (NCs) have shown promising application in photocatalytic CO2 reduction, but their activities are still largely restrained by severe charge recombination and narrow solar spectrum response. Assembly of heterojunctions can be beneficial to the charge separation in MHPs while the assembly process usually brings native interfacial defects, impeding efficient charge separation between two materials. Herein, an in‐situ generation strategy was developed to prepare CsPbBr3/WO3 heterojunction, using WO3 nanosheets (NSs) as growing substrate for the growth of CsPbBr3 NCs. The developed CsPbBr3/WO3 heterojunction exhibited a high‐quality interface, greatly facilitating charge transfer between two semiconductors. The hybrid photocatalyst displayed an excellent activity toward CO2 reduction, which was about 7‐fold higher than pristine CsPbBr3 NCs and 3.5‐fold higher than their assembled counterparts. The experimental results and theoretical simulations revealed that a Z‐scheme mechanism with a favorable internal electric field was responsible for the good performance of CsPbBr3/WO3 heterojunction. By using O‐defective WO3 NSs as a near‐infrared (NIR) light absorber, the CsPbBr3/WO3 heterojunction could harvest NIR light and showed an impressive activity toward CO2 reduction. This work demonstrates a new strategy to design MHP‐based heterojunctions by synergistically considering the interface quality, charge transfer mode, interfacial electric field, and light response range between two semiconductors.

Red‐Light‐Driven CO2Photoreduction into CH4and CO Enabled by Narrow‐Gap Conjugated Microporous Polymers

“…As reported in our previous studies, inductively coupled plasma-mass spectrometry (ICP-MS) analysis indicated the presence of 0.31-0.40 wt% Pd and 0.012-0.042 wt% Cu in the porous polymer due to residual catalyst. [19,25] The formation of polymer networks was verified by cross-polarization/magic angle spinning (CP/MAS) 13 C NMR spectra and Fourier transform infrared (FT-IR) spectra (Figure S2-S5, Supporting Information). The 13 C NMR spectra showed peaks at approximately 120-140 ppm for all polymers, which could be assigned to sp 2 hybridized carbons.…”

“…However, compared to the large amount of research work done in the visible range with light wavelength of 420–550 nm, red light with low photoenergy has been rarely used for photocatalysis. To date, only a very limited number of photocatalysts have been reported for photocatalytic CO 2 reduction under light irradiation above 600 nm, such as Os(II)–Re(I) supramolecular complexes, [ 8 ] Ru complex/Ni–Al layered double hydroxide, [ 9 ] carbon dots/Bi 2 WO 6 , [ 10 ] ZnO/carbon dots, [ 11 ] Bi 2 O 3− x with oxygen vacancies, [ 12 ] CsPbBr 3 /WO 3 , [ 13 ] g‐C 3 N 4 /WO 3 ·H 2 O/Pd heterostructure, [ 14 ] etc. Among the studied photocatalysts, most are compositing materials, suffering from complicated preparation, low photocatalytic activity, and potential environmental issues resulting from the harmful heavy metals such as Cd, W, and Pb.…”

Mn‐Doped Perovskite Nanocrystals for Photocatalytic CO2 Reduction: Insight into the Role of the Charge Carriers with Prolonged Lifetime

“…[ 6,7 ] In recent years, various kinds of perovskite photocatalysts have been developed, and they have exhibited great potential in photocatalysis. [ 8–31 ] However, the current perovskite photocatalytic systems generally have severe charge recombination. [ 22 ] The undesired charge recombination largely limits the transfer efficiency of the photogenerated charge carriers, which becomes the bottleneck in the development of the perovskite photocatalysts.…”

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

“…Specifically, embedding CsPbBr 3 into protective materials has to face many uncertainties such as reducing the absorption of light 32 or undesirability interface for inefficient charge transfer/separation. 33 Generally, the tighter the contact between the composites and the larger the area, the faster the photogenerated charge transport. 34 Moreover, reducing the size of each component of photocatalytic heterojunction materials has been demonstrated to be an effective strategy for maximizing carrier transport.…”