In this study,Ni_(2)P/CdS composites were constructed by depositing non-precious metal co-catalyst Ni_(2)P on a one-dimensional network of CdS using a simple in-situ photodeposition method.The prepared photocatalysts ...In this study,Ni_(2)P/CdS composites were constructed by depositing non-precious metal co-catalyst Ni_(2)P on a one-dimensional network of CdS using a simple in-situ photodeposition method.The prepared photocatalysts promoted the decomposition of ethanol into high-value-added products while generating hydrogen.The composite photoanodes loaded with the Ni_(2)P co-catalysts showed significantly higher ethanol conversion and hydrogen production in the visible light region,which was almost three times higher than that of pure CdS.The main products of photocatalytic ethanol production are acetaldehyde(AA)and 2,3-butanediol(2,3-BDA).Compared with CdS,the selectivity of the composite photocatalysts for converting ethanol to acetaldehyde was significantly improved(62% to 78%).Characterization of the prepared photocatalysts confirmed that the loading of Ni_(2)P co-catalysts on CdS not only broadened the optical region of the catalysts for trapping light but also effectively promoted the separation and transfer of charge carriers,which significantly improved the photocatalytic efficiency of ethanol conversion and hydrogen production in the catalysts.It has been proven through Electron Paramagnetic Resonance testing that loading a Ni_(2)P co-catalyst on CdS is beneficial for the adsorption of hydroxyethyl radicals(*CH(OH)CH_(3)),thereby further improving the selectivity of acetaldehyde.This study plays an important role in the rational design of composite catalyst structures and the introduction of co-catalysts to improve catalyst performance,promote green chemistry,advocate a low-carbon society,and promote sustainable development.展开更多
Artificial photosynthesis is an ideal method for solar-to-chemical energy conversion,wherein solar energy is stored in the form of chemical bonds of solar fuels.In particular,the photocatalytic reduction of CO_(2)has ...Artificial photosynthesis is an ideal method for solar-to-chemical energy conversion,wherein solar energy is stored in the form of chemical bonds of solar fuels.In particular,the photocatalytic reduction of CO_(2)has attracted considerable attention due to its dual benefits of fossil fuel production and CO_(2)pollution reduction.However,CO_(2)is a comparatively stable molecule and its photoreduction is thermodynamically and kinetically challenging.Thus,the photocatalytic efficiency of CO_(2)reduction is far below the level of industrial applications.Therefore,development of low-cost cocatalysts is crucial for significantly decreasing the activation energy of CO_(2)to achieving efficient photocatalytic CO_(2)reduction.Herein,we have reported the use of a Ni_(2)P material that can serve as a robust cocatalyst by cooperating with a photosensitizer for the photoconversion of CO_(2).An effective strategy for engineering Ni_(2)P in an ultrathin layered structure has been proposed to improve the CO_(2)adsorption capability and decrease the CO_(2)activation energy,resulting in efficient CO_(2)reduction.A series of physicochemical characterizations including X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),transmission electron microscopy(TEM),high-resolution transmission electron microscopy(HRTEM),and atomic force microscopy(AFM)were used to demonstrate the successful preparation of ultrathin Ni_(2)P nanosheets.The XRD and XPS results confirm the successful synthesis of Ni_(2)P from Ni(OH)2 by a low temperature phosphidation process.According to the TEM images,the prepared Ni_(2)P nanosheets exhibit a 2D and near-transparent sheet-like structure,suggesting their ultrathin thickness.The AFM images further demonstrated this result and also showed that the height of the Ni_(2)P nanosheets is ca 1.5 nm.The photoluminescence(PL)spectroscopy results revealed that the Ni_(2)P material could efficiently promote the separation of the photogenerated electrons and holes in[Ru(bpy)3]Cl2?6H2O.More importantly,the Ni_(2)P nanosheets could more efficiently promote the charge transfer and charge separation rate of[Ru(bpy)3]Cl2?6H2O compared with the Ni_(2)P particles.In addition,the electrochemical experiments revealed that the Ni_(2)P nanosheets,with their high active surface area and charge conductivity,can provide more active centers for CO_(2)conversion and accelerate the interfacial reaction dynamics.These results strongly suggest that the Ni_(2)P nanosheets are a promising material for photocatalytic CO_(2)reduction,and can achieve a CO generation rate of 64.8μmol·h^(-1),which is 4.4 times higher than that of the Ni_(2)P particles.In addition,the XRD and XPS measurements of the used Ni_(2)P nanosheets after the six cycles of the photocatalytic CO_(2)reduction reaction demonstrated their high stability.Overall,this study offers a new function for the 2D transition-metal phosphide catalysts in photocatalytic CO_(2)reduction.展开更多
基金supported by the National Natural Science Foundation of China(22075197,22278290)the Shanxi Provincial Natural Science Foundation of China(202103021224079,201903D421081)the Research and Development Project of Key Core and Common Technology of Shanxi Province(20201102018)。
文摘In this study,Ni_(2)P/CdS composites were constructed by depositing non-precious metal co-catalyst Ni_(2)P on a one-dimensional network of CdS using a simple in-situ photodeposition method.The prepared photocatalysts promoted the decomposition of ethanol into high-value-added products while generating hydrogen.The composite photoanodes loaded with the Ni_(2)P co-catalysts showed significantly higher ethanol conversion and hydrogen production in the visible light region,which was almost three times higher than that of pure CdS.The main products of photocatalytic ethanol production are acetaldehyde(AA)and 2,3-butanediol(2,3-BDA).Compared with CdS,the selectivity of the composite photocatalysts for converting ethanol to acetaldehyde was significantly improved(62% to 78%).Characterization of the prepared photocatalysts confirmed that the loading of Ni_(2)P co-catalysts on CdS not only broadened the optical region of the catalysts for trapping light but also effectively promoted the separation and transfer of charge carriers,which significantly improved the photocatalytic efficiency of ethanol conversion and hydrogen production in the catalysts.It has been proven through Electron Paramagnetic Resonance testing that loading a Ni_(2)P co-catalyst on CdS is beneficial for the adsorption of hydroxyethyl radicals(*CH(OH)CH_(3)),thereby further improving the selectivity of acetaldehyde.This study plays an important role in the rational design of composite catalyst structures and the introduction of co-catalysts to improve catalyst performance,promote green chemistry,advocate a low-carbon society,and promote sustainable development.
文摘Artificial photosynthesis is an ideal method for solar-to-chemical energy conversion,wherein solar energy is stored in the form of chemical bonds of solar fuels.In particular,the photocatalytic reduction of CO_(2)has attracted considerable attention due to its dual benefits of fossil fuel production and CO_(2)pollution reduction.However,CO_(2)is a comparatively stable molecule and its photoreduction is thermodynamically and kinetically challenging.Thus,the photocatalytic efficiency of CO_(2)reduction is far below the level of industrial applications.Therefore,development of low-cost cocatalysts is crucial for significantly decreasing the activation energy of CO_(2)to achieving efficient photocatalytic CO_(2)reduction.Herein,we have reported the use of a Ni_(2)P material that can serve as a robust cocatalyst by cooperating with a photosensitizer for the photoconversion of CO_(2).An effective strategy for engineering Ni_(2)P in an ultrathin layered structure has been proposed to improve the CO_(2)adsorption capability and decrease the CO_(2)activation energy,resulting in efficient CO_(2)reduction.A series of physicochemical characterizations including X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),transmission electron microscopy(TEM),high-resolution transmission electron microscopy(HRTEM),and atomic force microscopy(AFM)were used to demonstrate the successful preparation of ultrathin Ni_(2)P nanosheets.The XRD and XPS results confirm the successful synthesis of Ni_(2)P from Ni(OH)2 by a low temperature phosphidation process.According to the TEM images,the prepared Ni_(2)P nanosheets exhibit a 2D and near-transparent sheet-like structure,suggesting their ultrathin thickness.The AFM images further demonstrated this result and also showed that the height of the Ni_(2)P nanosheets is ca 1.5 nm.The photoluminescence(PL)spectroscopy results revealed that the Ni_(2)P material could efficiently promote the separation of the photogenerated electrons and holes in[Ru(bpy)3]Cl2?6H2O.More importantly,the Ni_(2)P nanosheets could more efficiently promote the charge transfer and charge separation rate of[Ru(bpy)3]Cl2?6H2O compared with the Ni_(2)P particles.In addition,the electrochemical experiments revealed that the Ni_(2)P nanosheets,with their high active surface area and charge conductivity,can provide more active centers for CO_(2)conversion and accelerate the interfacial reaction dynamics.These results strongly suggest that the Ni_(2)P nanosheets are a promising material for photocatalytic CO_(2)reduction,and can achieve a CO generation rate of 64.8μmol·h^(-1),which is 4.4 times higher than that of the Ni_(2)P particles.In addition,the XRD and XPS measurements of the used Ni_(2)P nanosheets after the six cycles of the photocatalytic CO_(2)reduction reaction demonstrated their high stability.Overall,this study offers a new function for the 2D transition-metal phosphide catalysts in photocatalytic CO_(2)reduction.
