Photoelectrocatalytic reduction of CO_2 into formic acid using WO_(3-x)/TiO_2 film as novel photoanode

新型WO_(3-x)/TiO_2薄膜光阳极光电催化还原CO_2制备甲酸（英文）

A novel WO3-x/TiO2 film as photoanode was synthesized for photoelectrocatalytic（PEC） reduction of CO2 into formic acid（HCOOH）. The films prepared by doctor blade method were characterized with X-ray diffractometer（XRD）, scanning electron microscope（SEM） and transmission electron microscope（TEM）. The existence of oxygen vacancies in the WO3-x was confirmed with an X-ray photoelectron spectroscopy（XPS）, and the accurate oxygen index was determined by a modified potentiometric titrimetry method. After 3h of photoelectrocatalytic reduction, the formic acid yield of the WO3-x/TiO2 film is 872 nmol/cm^2, which is 1.83 times that of the WO3/TiO2 film. The results of PEC performance demonstrate that the introduction of WO3-x nanoparticles can improve the charge transfer performance so as to enhance the performance of PEC reduction of CO2 into formic acid.

采用刮涂法制备一种新型光阳极WO_(3-x)/TiO_2薄膜,并对其进行光电催化还原CO_2制备甲酸。运用X射线衍射(XRD)、扫描电镜(SEM)和透射电镜(TEM)对光阳极薄膜进行表征。通过XPS确认WO_(3-x)中存在氧空位,并通过电位滴定法精确测定WO_(3-x)中的氧指数。光电催化还原CO_2 3h后,WO_(3-x)/TiO_2薄膜光阳极的甲酸产量为872nmol/cm2,是WO_3/TiO_2薄膜光阳极的1.83倍。光电化学测试表明,由于氧空位的存在提高材料电荷传输性能,从而提高光电催化还原CO_2活性,故WO_(3-x)/TiO_2薄膜光阳极相对WO_3/TiO_2具有更好的光电催化还原活性。