The production of renewable methanol(CH_(3)OH)via the photocatalytic hydrogenation of CO_(2) is an ideal method to ameliorate energy shortages and mitigate CO_(2) emissions:however,the highly selective synthesis of me...The production of renewable methanol(CH_(3)OH)via the photocatalytic hydrogenation of CO_(2) is an ideal method to ameliorate energy shortages and mitigate CO_(2) emissions:however,the highly selective synthesis of methanol at atmospheric pressure remains challenging owing to the competing reverse water-gas shift(RWGS)reaction.Herein,we present a novel approach for the synthesis of CH_(3)OH via photocatalytic CO_(2) hydrogenation using a catalyst featuring highly dispersed Au nanoparticles loaded on oxygen vacancy(OV)-rich molybdenum dioxide(MoO_(2)),resulting in a remarkable selectivity of 43.78%.The active sites in the Au/MoO_(2) catalyst are high-density Au-oxygen vacancies,which synergistically promote the tandem methanol synthesis via an initial RWGS reaction and subsequent CO hydrogenation.This work provides comprehensive insights into the design of metal-vacancy synergistic sites for the highly selective photocatalytic hydrogenation of CO_(2) to CH_(3)OH.展开更多
The interface modulation significantly affects the photocatalytic performances of supported metal phthalocyanines(MPc)-based systems.Herein,ZnPc was loaded on nanosized Au-modified TiO_(2)nanosheets(Au-T)to obtain wid...The interface modulation significantly affects the photocatalytic performances of supported metal phthalocyanines(MPc)-based systems.Herein,ZnPc was loaded on nanosized Au-modified TiO_(2)nanosheets(Au-T)to obtain wide-spectrum ZnPc/Au-T photocatalysts.Compared with large Au NP(8 nm)-mediated ZnPc/Au-T photocatalyst,ultrasmall Au NP(3 nm)-mediated one shows advantageous photoactivity,achieving 3-and 10-fold CO_(2)conversion rates compared with reference ZnPc/T and pristine TiO_(2)nanosheets,respectively.Employing monochromatic beam-assisted surface photovoltage and photocurrent action,etc.,the introduction of ultrasmall Au NPs more effectively facilitates intrinsic interfacial charge transfer.Moreover,ZnP c molecules are found more dispersed with the existence of small Au NPs hence exposing abundant Zn^(2+)sites as the catalytic center for CO_(2)reduction.This work provides a feasible design strategy and renewed recognition for supported MPc-based photocatalyst systems.展开更多
Recently, the noble metal Au has been widely applied as the cocatalyst for improving the photocatalytic reduction of CO_(2). However, the metallic Au exhibits weak adsorption strength towards CO_(2) due to its intrins...Recently, the noble metal Au has been widely applied as the cocatalyst for improving the photocatalytic reduction of CO_(2). However, the metallic Au exhibits weak adsorption strength towards CO_(2) due to its intrinsic electronic structure with d-orbitals fully filled, thus limiting the activation and reduction of CO_(2). To address this issue and maximize the photoreduction of CO_(2), herein we have designed Au@CZS@MO-400 triple-shelled hollow nanospheres by depositing Cd_(0.7)Zn_(0.3)S (CZS) on the outer surface of the MO-400 (MnO_(2) annealed at 400 ℃) hollow nanospheres and then Au nanoparticles on the CZS surface. It is manifested that the resultant 3%Au@CZS@MO-400 achieves a remarkably boosted photoreduction of CO_(2) with the CO/CH_(4) yield rates as high as 68.25/12.42 µmol g^(-1) h^(-1), increased by 3.7/1.5 times over MO-400 and 12.9/1.5 times over CZS. The combined analyses from X-ray photoelectron spectroscopy and density functional theory calculations confirm the creation of electron-deficient Auδ+ active sites by modulating their electron configuration by CZS, consequently decreasing the CO_(2)-Au antibonding-orbital occupancy to reinforce the adsorption strength of CO_(2) onto the Au active sites and in turn boost the photoreduction of CO_(2). Moreover, it is demonstrated that the Au@CZS@MO-400 hollow nanospheres are quite efficient for supplying the Au cocatalyst with photoelectrons for CO_(2) reduction reactions due to the good energy band matching, unique hollow structure and high electron spin polarization of MO-400. This work provides important guidance for understanding and modifying photocatalysts to maximize their photoreduction of CO_(2).展开更多
Solar-driven H_(2)O_(2) production through artificial photosynthesis presents a promising alternative to anthraquinone,given its lower energy consumption and eco-friendly nature[1-3].However,its catalytic performance ...Solar-driven H_(2)O_(2) production through artificial photosynthesis presents a promising alternative to anthraquinone,given its lower energy consumption and eco-friendly nature[1-3].However,its catalytic performance is severely restricted by the inefficient separation of photogenerated carriers and interface reactions[4,5].展开更多
TiO2 nanotubes were prepared under normal pressure at a temperature of 120 ℃. Ag, Au, Pt nanoparticles supported on TiO2 nanotubes were prepared by m icrowave assisted heating polyol process. TEM images showed that m...TiO2 nanotubes were prepared under normal pressure at a temperature of 120 ℃. Ag, Au, Pt nanoparticles supported on TiO2 nanotubes were prepared by m icrowave assisted heating polyol process. TEM images showed that microwave prepa red Ag, Au, Pt nanoparticles supported on TiO2 nanotubes were small and well dis persed on the surface of the TiO2 nanotubes. UV-Vis absorption spectra showed th at the absorbance of Ag/TiO2 nanotubes and Au/TiO2 nanotubes in the visible ligh t range increased greatly compared to the single titania nanotubes.展开更多
文摘The production of renewable methanol(CH_(3)OH)via the photocatalytic hydrogenation of CO_(2) is an ideal method to ameliorate energy shortages and mitigate CO_(2) emissions:however,the highly selective synthesis of methanol at atmospheric pressure remains challenging owing to the competing reverse water-gas shift(RWGS)reaction.Herein,we present a novel approach for the synthesis of CH_(3)OH via photocatalytic CO_(2) hydrogenation using a catalyst featuring highly dispersed Au nanoparticles loaded on oxygen vacancy(OV)-rich molybdenum dioxide(MoO_(2)),resulting in a remarkable selectivity of 43.78%.The active sites in the Au/MoO_(2) catalyst are high-density Au-oxygen vacancies,which synergistically promote the tandem methanol synthesis via an initial RWGS reaction and subsequent CO hydrogenation.This work provides comprehensive insights into the design of metal-vacancy synergistic sites for the highly selective photocatalytic hydrogenation of CO_(2) to CH_(3)OH.
基金supported by the National Natural Science Foundation of China(Nos.U2102211 and 22378101)the Fundamental Research Foundation for Universities of Heilongjiang Province(No.2021-KYYWF-0004)the Science Fund for Distinguished Young Scholars of Heilongjiang University(No.JCL202102)。
文摘The interface modulation significantly affects the photocatalytic performances of supported metal phthalocyanines(MPc)-based systems.Herein,ZnPc was loaded on nanosized Au-modified TiO_(2)nanosheets(Au-T)to obtain wide-spectrum ZnPc/Au-T photocatalysts.Compared with large Au NP(8 nm)-mediated ZnPc/Au-T photocatalyst,ultrasmall Au NP(3 nm)-mediated one shows advantageous photoactivity,achieving 3-and 10-fold CO_(2)conversion rates compared with reference ZnPc/T and pristine TiO_(2)nanosheets,respectively.Employing monochromatic beam-assisted surface photovoltage and photocurrent action,etc.,the introduction of ultrasmall Au NPs more effectively facilitates intrinsic interfacial charge transfer.Moreover,ZnP c molecules are found more dispersed with the existence of small Au NPs hence exposing abundant Zn^(2+)sites as the catalytic center for CO_(2)reduction.This work provides a feasible design strategy and renewed recognition for supported MPc-based photocatalyst systems.
基金supported by the Gansu Province Outstanding PhD Student Fund(No.24JRRA206)the National Natural Sci-ence Foundation of China(No.52162040).
文摘Recently, the noble metal Au has been widely applied as the cocatalyst for improving the photocatalytic reduction of CO_(2). However, the metallic Au exhibits weak adsorption strength towards CO_(2) due to its intrinsic electronic structure with d-orbitals fully filled, thus limiting the activation and reduction of CO_(2). To address this issue and maximize the photoreduction of CO_(2), herein we have designed Au@CZS@MO-400 triple-shelled hollow nanospheres by depositing Cd_(0.7)Zn_(0.3)S (CZS) on the outer surface of the MO-400 (MnO_(2) annealed at 400 ℃) hollow nanospheres and then Au nanoparticles on the CZS surface. It is manifested that the resultant 3%Au@CZS@MO-400 achieves a remarkably boosted photoreduction of CO_(2) with the CO/CH_(4) yield rates as high as 68.25/12.42 µmol g^(-1) h^(-1), increased by 3.7/1.5 times over MO-400 and 12.9/1.5 times over CZS. The combined analyses from X-ray photoelectron spectroscopy and density functional theory calculations confirm the creation of electron-deficient Auδ+ active sites by modulating their electron configuration by CZS, consequently decreasing the CO_(2)-Au antibonding-orbital occupancy to reinforce the adsorption strength of CO_(2) onto the Au active sites and in turn boost the photoreduction of CO_(2). Moreover, it is demonstrated that the Au@CZS@MO-400 hollow nanospheres are quite efficient for supplying the Au cocatalyst with photoelectrons for CO_(2) reduction reactions due to the good energy band matching, unique hollow structure and high electron spin polarization of MO-400. This work provides important guidance for understanding and modifying photocatalysts to maximize their photoreduction of CO_(2).
文摘Solar-driven H_(2)O_(2) production through artificial photosynthesis presents a promising alternative to anthraquinone,given its lower energy consumption and eco-friendly nature[1-3].However,its catalytic performance is severely restricted by the inefficient separation of photogenerated carriers and interface reactions[4,5].
文摘TiO2 nanotubes were prepared under normal pressure at a temperature of 120 ℃. Ag, Au, Pt nanoparticles supported on TiO2 nanotubes were prepared by m icrowave assisted heating polyol process. TEM images showed that microwave prepa red Ag, Au, Pt nanoparticles supported on TiO2 nanotubes were small and well dis persed on the surface of the TiO2 nanotubes. UV-Vis absorption spectra showed th at the absorbance of Ag/TiO2 nanotubes and Au/TiO2 nanotubes in the visible ligh t range increased greatly compared to the single titania nanotubes.
