The visible light photocatalytic activity of two-dimensional （2D） BiOl microplates was intensively enhanced through simply dipping in Na2CO3 solutions at room temperature. The X-ray powder diffrac- tion （XRD） and ...The visible light photocatalytic activity of two-dimensional （2D） BiOl microplates was intensively enhanced through simply dipping in Na2CO3 solutions at room temperature. The X-ray powder diffrac- tion （XRD） and scanning electron microscopy （SEM） investigations suggest that little amount of （BiO）2CO3 phase was formed on the surface of 2D BiOI via the in situ chemical conversion. The concen- tration of Na2CO3 solutions affected the structure, morphology, light absorption and surface element component of 2D BiOl. The surface loaded （BiO）2CO3 mainly trapped the photoinduced electrons of BiOI, improved the separation efficiency of photocharges and finally raised the photocatalytic activity of BiOl under visible light （λ 〉 420 nm）. Furthermore, the product of the as-prepared （BiO）2CO3/BiOI displayed excellent stability in the repeated experiment. This study provides a facile way to improve the photocatalytic activity of BiOX （X = CI, Br, I） by means of surface treatment with Na2CO3 solutions.展开更多
Two-dimensional(2D)mesoporous metal-oxide(hydroxide)nanomaterials with defects are promising towards the realization of efficient electrocatalysis.Herein,we report a facile and effective one-pot solvothermal route to ...Two-dimensional(2D)mesoporous metal-oxide(hydroxide)nanomaterials with defects are promising towards the realization of efficient electrocatalysis.Herein,we report a facile and effective one-pot solvothermal route to synthesize mesoporous Mo_(x)-Co-O hybrid nanosheets(NSs)which is composed of crystalline Mo_(4)O_(11) and amorphous cobalt hydroxide.Due to the corrosion of 1-octylamine at high temperatures,abundant mesoporous holes are created in situ over the Mo_(x)-Co-O hybrid NSs during the solvothermal process,which is beneficial to increasing the electrochemical surface area.The dimension of the Mox-Co-O NSs,size of mesoporous and the concentration of defects can be easily modulated by controlling the molar ratio of Mo/Co.Electrochemical measurements reveal that the 2D mesoporous Mo_(x)-Co-O NSs show an excellent activity for the oxygen evolution reaction with the highest catalytic activity of η_(10)=276 mV at 10 mA cm^(−2)in 1 mol L^(−1)KOH.Enhanced adsorption of intermediates and abundant oxygen vacancies achieved by appropriate Mo doping are the two main factors that contribute to the excellent catalytic activity of Mo_(0.2)-Co-O NSs.This work,with the construction of 2D metal-oxide(hydroxide)crystallineamorphous nanomaterials possessing abundant holes,oxygen vacancies and enhanced adsorption of intermediates,provides important insight on the design of more efficient catalysts.展开更多
In this study, the electrochemical behavior of monocrystalline bare Si and Ag-coated Si in hydrofluoric acid （HF） solutions with and without hydrogen peroxide （H202） was systematically tested with an electrochemic...In this study, the electrochemical behavior of monocrystalline bare Si and Ag-coated Si in hydrofluoric acid （HF） solutions with and without hydrogen peroxide （H202） was systematically tested with an electrochemical technique. By analyzing the po- larization curves, the corrosion processes were quantified and the etchants which govern the formation of silicon nanowires （SiNWs） were determined. It was discovered that both H202 and Ag enhanced the reduction reactions, irrespective of the con- ductivity type and doping concentration of Si. It is believed that the formation of SiNWs via Metal-Catalyzed Electroless Etching is a process controlled by cathodic reduction reactions.展开更多
基金supported by the National Natural Science Foundation of China (51472005, 51272081)the Natural Science Foundation of Educational Committee of Anhui Province (gxyq ZD2016413, gxyq ZD2016414, and KJ2015A027)+1 种基金the Natural Science Foundation of Anhui Province (1708085MB32)Innovation Team of Design and Application of Advanced Energetic Materials
文摘The visible light photocatalytic activity of two-dimensional （2D） BiOl microplates was intensively enhanced through simply dipping in Na2CO3 solutions at room temperature. The X-ray powder diffrac- tion （XRD） and scanning electron microscopy （SEM） investigations suggest that little amount of （BiO）2CO3 phase was formed on the surface of 2D BiOI via the in situ chemical conversion. The concen- tration of Na2CO3 solutions affected the structure, morphology, light absorption and surface element component of 2D BiOl. The surface loaded （BiO）2CO3 mainly trapped the photoinduced electrons of BiOI, improved the separation efficiency of photocharges and finally raised the photocatalytic activity of BiOl under visible light （λ 〉 420 nm）. Furthermore, the product of the as-prepared （BiO）2CO3/BiOI displayed excellent stability in the repeated experiment. This study provides a facile way to improve the photocatalytic activity of BiOX （X = CI, Br, I） by means of surface treatment with Na2CO3 solutions.
基金the National Key R&D Program of China(2020YFB1505802)the Ministry of Science and Technology(2017YFA0208200)+1 种基金the National Natural Science Foundation of China(22025108,U21A20327,and 22121001)the Start-up Funds from Xiamen University.
文摘Two-dimensional(2D)mesoporous metal-oxide(hydroxide)nanomaterials with defects are promising towards the realization of efficient electrocatalysis.Herein,we report a facile and effective one-pot solvothermal route to synthesize mesoporous Mo_(x)-Co-O hybrid nanosheets(NSs)which is composed of crystalline Mo_(4)O_(11) and amorphous cobalt hydroxide.Due to the corrosion of 1-octylamine at high temperatures,abundant mesoporous holes are created in situ over the Mo_(x)-Co-O hybrid NSs during the solvothermal process,which is beneficial to increasing the electrochemical surface area.The dimension of the Mox-Co-O NSs,size of mesoporous and the concentration of defects can be easily modulated by controlling the molar ratio of Mo/Co.Electrochemical measurements reveal that the 2D mesoporous Mo_(x)-Co-O NSs show an excellent activity for the oxygen evolution reaction with the highest catalytic activity of η_(10)=276 mV at 10 mA cm^(−2)in 1 mol L^(−1)KOH.Enhanced adsorption of intermediates and abundant oxygen vacancies achieved by appropriate Mo doping are the two main factors that contribute to the excellent catalytic activity of Mo_(0.2)-Co-O NSs.This work,with the construction of 2D metal-oxide(hydroxide)crystallineamorphous nanomaterials possessing abundant holes,oxygen vacancies and enhanced adsorption of intermediates,provides important insight on the design of more efficient catalysts.
基金supported by the National Basic Research Program of China("973"Project)(Grant No.2012CB932400)China Postdoctoral Science Foundation(Grant No.2014M560934)
文摘In this study, the electrochemical behavior of monocrystalline bare Si and Ag-coated Si in hydrofluoric acid （HF） solutions with and without hydrogen peroxide （H202） was systematically tested with an electrochemical technique. By analyzing the po- larization curves, the corrosion processes were quantified and the etchants which govern the formation of silicon nanowires （SiNWs） were determined. It was discovered that both H202 and Ag enhanced the reduction reactions, irrespective of the con- ductivity type and doping concentration of Si. It is believed that the formation of SiNWs via Metal-Catalyzed Electroless Etching is a process controlled by cathodic reduction reactions.
