钴掺杂锰酸镧光催化剂的第一性原理与可见光响应光催化性能研究

Cobalt Substitutions in Lanthanum Manganate Photocatalyst:First-principles and Visible-light Photocatalytic Ability Investigation

利用了第一性原理方法模拟计算了LaMnO_(3)在掺杂Co前后的电子性质和光学性能,计算结果表明,掺杂Co可以提高LaMnO_(3)对可见光的吸收能力.探究了不同pH环境下采用溶胶-凝胶法制备的LaMnO_(3)结构的稳定性,多种表征手段的结果表明,LaMnO_(3)在中性或碱性环境下较为稳定.研究了不同Co掺杂浓度对LaMnO_(3)光催化活性的影响.其中,LaMn_(0.9)Co_(0.1)O_(3)粉体表现出最高的光催化活性,在可见光照射下对甲基橙溶液的降解率达54%,比LaMnO_(3)提高了17%.

Perovskite photocatalyst has attracted many attention due to its good stability and perfect catalytic decontamination ability.Sol-gel method can effectively and stably synthetize LaMnO_(3).Perovskite can effectively adjust the bandgap with substitute B site of metal and improve its catalytic performance.In this paper,The electronic and optical properties of LaMnO_(3)and the combination of La Mn_(1-x)CoxO_(3) were simulated by the first principle method.The results showed that Co substitutions can improve the absorption ability to visible light of LaMnO_(3).LaMnO_(3)was synthetized by sol-gel method,and the stability of the structure under different p H environment was explored.The results showed that LaMnO_(3)was more stable under neutral or alkaline environment.The effect of LaMnO_(3) in different Co substitution concentration on the photocatalytic activity was studied.Among that,the results of experiment prove that the Co substitutions in LaMnO_(3)can improve the photocatalysis ability of LaMnO_(3).Compare with other proportion of Co substitutions,LaMn_(0.9)Co_(0.1)O_(3)powder showed the highest photocatalytic activity,and the degradation rate of methyl orange under visible light was 54%,which is 17%higher than that of LaMnO_(3).