Search

The photocatalytic CO2reduction technology can effectively decrease the CO2content in air while converting CO2into high-value-added chemicals and turning waste into treasure. In this study, Cu2O with a concave cubic structure was fabricated by selective etching, and ZnIn2S4nanosheets were successfully loaded on it uniformly, which significantly elevated its catalytic activity. The maximum CO yield of 9.98 μmol/g/h was obtained on the Z-scheme ZIS/Cu2O-0.3 photocatalyst, which was 3.7 and 4.3 times as high as the bare Cu2O concave cube and ZnIn2S4, respectively. The excellent photocatalytic performance could be attributed to the construction of Z-scheme heterojunction which facilitated the efficient separation of electron–hole pairs, a large specific surface area that provided an abundance of reactive sites, and positive visible light response.

Photoreduction of CO2can effectively alleviate the troublesome global energy crisis and environmental problems by converting CO2into hydrocarbons. Due to the discovery of photocatalysts that can respond to infrared light, the application of full spectrum in photocatalysis has attracted many researchers. This review comprehensively summarizes the progress in CO2photocatalytic reduction based on full-spectrum photocatalytic systems, and the basic theory of photoresponse, the mechanism of photocatalysis and photoreduction of CO2, and the representative photocatalytic materials working under ultraviolet, visible, and infrared irradiation are discussed. The strategies and related mechanisms of realizing full-spectrum photocatalysis are introduced, and the contribution of photoreactors to CO2photocatalytic reduction is also mentioned. Finally, the application prospects of light-driven reactions in CO2reduction are prospected. It is hoped that this review can offer clearer guidance for CO2reduction and construction of full spectrum-driven photocatalyst for efficient photocatalytic CO2reduction in the future.

Constructing heterostructures and designing excellent structures to simulate natural photosynthesis are effective ways to efficiently and selectively convert CO2into products with high energy. Herein, a novel 0D/3D heterostructure composed of Cd0.5Zn0.5S quantum dots and CdIn2S4nano-octahedron was resoundingly fabricated via a simple solvothermal–coprecipitation method. The optimal yields of CO2photoreduction to CO and CH4over the Cd0.5Zn0.5S/CdIn2S4composite material could reach up to 14.07 and 4.23 μmol/g/h, respectively, which was primarily due to the synergistic effect of the 0D/3D heterostructure and unique morphology, thus accelerating the transfer of light-induced carriers. In addition, the as-fabricated composite exhibited excellent stability and weaker photocorrosion. Hence, this work could provide a simple and efficient route for the design and construction of photocatalysts with superior activity for CO2photoreduction.

In this work, an urchinlike W18O49/g-C3N4composite was fabricated via a simple hydrothermal process. The photocatalytic CO2conversion reaction was applied to evaluate the photocatalytic behavior of this catalytic system, and the WOCN-20 wt % heterojunction displayed superior photocatalytic behavior under full spectrum light irradiation, which was 6.46 μmol·h–1·g–1for CO and 3.97 μmol·h–1·g–1for CH4, respectively. Furthermore, in the near-infrared region, the composite photocatalysts also displayed excellent photocatalytic performance. A large number of characterizations and testing measures were carried out to study the components, morphology, and physicochemical properties of W18O49/g-C3N4photocatalyst, which were helpful to exploring and understanding the reasons for the improvement of catalytic performance. The boosted activity resulted from the tight contact between W18O49and g-C3N4and the formation of a Z-scheme heterojunction. The local surface plasmonic resonance (LSPR) of W5+also contributed to the realization of efficient photocatalysis under near-infrared light. The Z-scheme electron transport model could realize the efficient separation of light-induced e––h+pairs and reduce the recombination rate, thereby boosting the CO2photocatalytic reduction process.

In this study, novel Schottky-junction photocatalysts Bi-metal-deposited g-C3N4were constructed via a one-step solvothermal process for photocatalytic CO2reduction under simulated irradiation. The photocatalytic performance illustrated that the nanohybrid catalysts have extreme activity and excellent stability. The maximum CO yield of 3.78 μmol h–1g–1was reached on the BiCN-0.6 hybrid, which was about 3 times as much as that of pure g-C3N4. The phase, microstructure, and optical and photoelectrochemical properties were demonstrated by related characterization methods. The improvement mechanism could be ascribed to the enhanced photon absorption capacity and the decreased recombination rate of photoinduced carriers arising from the Schottky barrier in the system. This work may provide a meaningful approach to enhance the photocatalytic activity through a simple and green strategy.

Nd was used as the modifier to improve the NH3-selective catalytic reduction (SCR) performance of MnOxcatalyst used in NOxabatement. The results of the activity test indicated that MnNdOx-0.1 catalyst displayed remarkable catalytic activity and N2selectivity in the temperature range of 50–300 °C. Characterization results proved the enhanced reducibility and the facilitated NH3and NOxadsorption over MnNdOx-0.1 catalyst, accompanied by the existence of more Mn4+and surface adsorbed oxygen species over its surface. The results of the in situ diffuse reflectance infrared Fourier transform study pointed out that the NH3-SCR reaction over the MnNdOx-0.1 catalyst was mainly under the control of the Langmuir–Hinshelwood mechanism (≤100 °C); when the reaction temperature was over 200 °C, the Eley–Rideal mechanism was dominant. More adsorbed NOxand NH3species over the MnNdOx-0.1 catalyst, along with the activation effect of Nd on the adsorbed reactants, had a facilitation impact on the SCR reaction process over the MnNdOx-0.1 catalyst.