Three‐in‐One Oxygen Vacancies: Whole Visible‐Spectrum Absorption, Efficient Charge Separation, and Surface Site Activation for Robust CO₂ Photoreduction

Abstract

A facile and controllable in situ reduction strategy is used to create surface oxygen vacancies (OVs) on Aurivillius‐phase Sr2Bi2Nb2TiO12 nanosheets, which were prepared by a mineralizer‐assisted soft‐chemical method. Introduction of OVs on the surface of Sr2Bi2Nb2TiO12 extends photoresponse to cover the whole visible region and also tremendously promotes separation of photoinduced charge carriers. Adsorption and activation of CO2 molecules on the surface of the catalyst are greatly enhanced. In the gas‐solid reaction system without co‐catalysts or sacrificial agents, OVs‐abundant Sr2Bi2Nb2TiO12 nanosheets show outstanding CO2 photoreduction activity, producing CO with a rate of 17.11 μmol g−1 h−1, about 58 times higher than that of the bulk counterpart, surpassing most previously reported state‐of‐the‐art photocatalysts. Our study provides a three‐in‐one integrated solution to advance the performance of photocatalysts for solar‐energy conversion and generation of renewable energy.

Unprecedented Eighteen‐Faceted BiOCl with a Ternary Facet Junction Boosting Cascade Charge Flow and Photo‐redox

“…Surface photovoltage spectroscopy (SPV) was used to investigate the charge separation degree. [26] Quantitatively,t he h trans was determined to be 94.02 %a nd 51.19 %f or BiOCl-100 and BiOCl-10, respectively,w ith adding the rapid electrons scavenger MVCl 2 (Figure 2d, Figure S16). [25] Electrochemical impedance spectra (EIS) indicate that the interfacial charge transfer of eighteen-faceted BiOCl is faster than that of BiOCl square plates ( Figure S15).…”

Isolated Square‐Planar Copper Center in Boron Imidazolate Nanocages for Photocatalytic Reduction of CO2 to CO

“…[1] Among these possible target products,the two-electron reduction of CO 2 to CO is al ess hindered process and plays an important role in the chemical industry. [9] Recent studies demonstrate that this type of catalyst exhibits high activity for reducing CO 2 to CO. [10] However, such ac atalyst is generally obtained through pyrolysis of Ni, or Co-based metal-organic frameworks (MOFs) or coordination polymers. Copper as an earth-abundant metal is ac ritical metal in photosynthesis [4] and Cu-based materials have been regarded as promising catalysts for efficiently photo-or electro-catalyzing CO 2 reduction.…”

“…[5] To date,v arious Cu-based catalysts have been developed but limited product selectivity due to the presence of multiple neighboring sites for involving CO 2 reduction. [9] Recent studies demonstrate that this type of catalyst exhibits high activity for reducing CO 2 to CO. [10] However, such ac atalyst is generally obtained through pyrolysis of Ni, or Co-based metal-organic frameworks (MOFs) or coordination polymers. [7] Besides these,i ntroducing single active site in ac atalyst has been proven to be an effective strategy to study the reactive pathway and enhance the activity for CO 2 reduction reaction (CO2RR).…”

“…To enhance product selectivity,aconventional approach is to tailor the number of nearest neighboring accessible Cu atoms,s uch as reducing the particle size [6] or hybridizing Cu with other metals. [9] Recent studies demonstrate that this type of catalyst exhibits high activity for reducing CO 2 to CO. [10] However, such ac atalyst is generally obtained through pyrolysis of Ni, or Co-based metal-organic frameworks (MOFs) or coordination polymers. [8] In particular,t he presence of unsaturated coordinated single active sites or defect can modify the electron structure of catalysts,w hich could stabilize the reaction intermediates and thus depress the energy barrier of the photoreduction CO 2 .…”

The Role of Polarization in Photocatalysis

“…[1] Since the TiO 2 single crystal was reported as aphotoelectrode for water splitting by Fujishima and Honda, photocatalytic applications of semiconductors have been considered ah ighly desirable and green strategy to solve the aforementioned problems.H ence,n umerous efforts are concentrated on developing excellent semiconductor photocatalysts. [1] Since the TiO 2 single crystal was reported as aphotoelectrode for water splitting by Fujishima and Honda, photocatalytic applications of semiconductors have been considered ah ighly desirable and green strategy to solve the aforementioned problems.H ence,n umerous efforts are concentrated on developing excellent semiconductor photocatalysts.…”