中文摘要：

以La（NO3）3为掺杂源,采用柠檬酸络合溶胶-凝胶法制备La^3＋掺杂BiVO4新型光催化剂,通过XPS、XRD、SEM、BET和UV-Vis等手段对其进行表征和分析。结果表明,制备的La^3＋掺杂BiVO4均为单斜白钨矿型,无其它杂质相生成,但晶体中V4＋和氧空缺增多,光吸收能力增强,且红移。但形貌和比表面积变化较小。La^3＋掺杂能有效提高BiVO4光催化活性,当掺杂量为0.02%（摩尔分数）时,BiVO4光催化效率最高,50min内对甲基橙溶液的脱色率达96%,较纯Bi-VO4提高63%左右。

英文摘要：

La^3＋ doped BiVO4 photocatalyst was synthesized by complexing sol-gel method using citric acid as chelate and characterized with XPS, XRD, SEM, BET and UV-Vis DRS. It revealed that pure BiVO4 and all the La^3＋ doped samples were monoclinic phases and no peaks o5 any other phases or impurities were detected. It also found that doping La^3＋ increased the amount of V4＋ , oxygen vacancies, the visible-light absorption and the absorbing boundary appear red shift, but little influence on morphology and the specific surface area. The pho- tocatalytic activity was evaluated by photocatalytic degradation of methyl orange （MO） solution under halogen lamp as visible light. Doping La^3＋ improved the photocatalytic activity and the highest photocatalytic degradation rate reached to be 96% when the La^3＋doped amount was 0.02%, which was more 58% or so than that of BiVO4 in 50min.