元素掺杂对V2O5/TiO2(001)表面活性的影响机制

Effect of Element Doping on the Surface Activity of V2Os/TiO2(001)

SCR催化剂改性是一种常用方法,但其改性元素的选择往往依靠经验性。鉴于此,本文针对F、N、Cu、La和Ce掺杂改性的V205/TiO2催化剂,拟从分子层面探讨其改性机理。基于密度泛函理论(DFT)计算了F、N、Cu、La和Ce掺杂V2O5/TiO2的键长、电荷、总能量和态密度。结果表明:F、N、Cu、La和Ce通过部分置换Ti进入TiO2晶体结构形成稳定结构,掺杂后总能量变低,带隙变小,有利于提高催化剂的催化活性。其中,Ce掺杂的效果明显优于其他元素的掺杂,对催化反应更加有利。

SCR catalyst modification is a common method,but the choice of modified elements often depends on experience.Therefore,the F,N,Cu,La and Ce doped V2 O5/TiO2 catalysts are proposed to be discussed at the molecular level.The bond length,charge,total energy and density of states of F,N,Cu,La and Ce doped V2 O5/TiO2 were calculated based on density functional theory(DFT).The results show that F,N,Cu,La and Ce doping form a stable structure by partially substituting Ti into the crystal structure of TiO2.The total energy is lower and the band gap is smaller than before,which is beneficial to improve the catalytic activity of the catalyst.The effect of Ce doping is more favorable for the catalytic reaction,which is obviously better than other elements.