摘要
用溶胶-凝胶方法制备了Ca2Fe2O5,采用浸渍法负载NiO制备了NiO/Ca2Fe2O5催化剂。采用X射线衍射、X射线光电子能谱和紫外-可见光漫反射光谱对催化剂进行了表征。Ca2Fe2O5和NiO/Ca2Fe2O5催化剂对可见光有良好的响应。考察了NiO/Ca2Fe2O5催化剂在可见光下分解水的光催化活性。实验结果表明,负载的NiO可以使光生电子和空穴得到较好的分离;溶液的初始pH对NiO/Ca2Fe2O5催化剂的光催化活性影响显著;NiO/Ca2Fe2O5催化剂光催化分解纯水的氢气生成速率为0.048μmol/(g.h),分解0.272mol/LNaHCO3溶液的氢气生成速率为84.857μmol/(g.h),NaHCO3中的HCO3-促进了光生电子和空穴的分离,从而提高了催化剂的光催化活性。
Nano Ca2Fe2O5 was prepared by sol-gel method and NiO was loaded by impregnation. Ca2Fe2O5 and NiO/Ca2Fe2O5 were characterized by means of XRD, XPS and UV-Vis DRS. Both Ca2Fe2O5 and NiO/Ca2Fe2O5 showed good response to visible light. The activity of NiO/Ca2Fe2O5 in photocatalytic splitting of water was studied under visible light irradiation. Loading of NiO promoted the separation of photogenerated electron and holes, and initial pH of the solution markedly affected the photocatalytic activity of NiO/Ca2Fe2O5. The rate of hydrogen generation by splitting pure water over NiO/Ca2Fe2O5 was 0. 048 μmol/（ g · h）. The photocatalytic activity obviously increased when NaHCO3 was added into water. The rate of hydrogen generation by splitting 0. 272 mol/L NaHCO3 solution over NiO/Ca2Fe2O5 is 84. 857 μmol/（ g · h）, HCO3 from NaHCO3 may consume the photogenerated holes and therefore enhances photocatalytic activity of the catalyst.
出处
《石油化工》
CAS
CSCD
北大核心
2009年第1期10-14,共5页
Petrochemical Technology
关键词
铁酸钙
光催化
分解水
制氢
calcium ferrite
photocatalysis
water splitting
hydrogen production
