Photocatalytic performance of K2Ti6O13 whiskers to H2 evolution and CO2 photo-reduction  

作　　者：L. F. Garay-Rodríguez L.M.Torres-Martínez E.Moctezuma 

机构地区：[1]Facultad de Ingeniería Civil-Departamento de Ecomateriales y Energía,Universidad Autónoma de Nuevo León,Av. Universidad S/N Cd. Universitaria,C. P. 66455 San Nicolás de los Garza,NL,México [2]Facultad de Ciencias Químicas,Universidad Autónoma de San Luis Potosí,Av. Manuel Nava#6,C. P.78290 San Luis Potosí,SLP,México

出　　处：《Journal of Energy Chemistry》2019年第10期18-28,共11页能源化学（英文版）

基　　金：CONACYT (CB-2014-237049, PDCPN-2015-487 and Ph. D. scholarship 635249) for the financial support

摘　　要：K2Ti6O13 whiskers were synthesized by conventional sol-gel method, sono-chemical assisted and microwave assisted sol-gel method in order to obtain catalysts with different particle sizes and to modify their optical, textural and electrochemical properties. These modifications improved their photocatalytic activity for H2 evolution and CO2 photo-reduction. Long K2Ti6O13 whiskers prepared by ultrasound assisted sol-gel method are the most active photocatalysts for the hydrogen evolution reaction using pure water as reactant (U-SG, 10,065 μmol g^-1). In contrast, an opposite behavior was observed using a mixture of ethanol-water, where the highest activity was achieved by the shortest and less crystalline K2Ti6O13 whiskers (C-SG, 3,2871 μmol g^-1). In case of CO2 photo-reduction, long whiskers that were also prepared by the sono-chemical assisted sol-gel method were the most active to transform CO2 to formaldehyde, methane, methanol and hydrogen. The EFB value of this catalyst is located very close to the potential for formaldehyde production and favors the selectivity to this organic product.K2Ti6O13 whiskers were synthesized by conventional sol-gel method, sono-chemical assisted and microwave assisted sol-gel method in order to obtain catalysts with different particle sizes and to modify their optical, textural and electrochemical properties. These modifications improved their photocatalytic activity for H2 evolution and CO2 photo-reduction. Long K2Ti6O13 whiskers prepared by ultrasound assisted sol-gel method are the most active photocatalysts for the hydrogen evolution reaction using pure water as reactant(U-SG, 10,065 μmol g-1). In contrast, an opposite behavior was observed using a mixture of ethanol-water, where the highest activity was achieved by the shortest and less crystalline K2Ti6O13 whiskers(C-SG, 3,2871 μmol g-1). In case of CO2 photo-reduction, long whiskers that were also prepared by the sono-chemical assisted sol-gel method were the most active to transform CO2 to formaldehyde,methane, methanol and hydrogen. The EFBvalue of this catalyst is located very close to the potential for formaldehyde production and favors the selectivity to this organic product.

关 键 词：K2Ti6O13 SOL-GEL WHISKERS HYDROGEN EVOLUTION CO2 reduction 

分 类 号：O4[理学—物理]