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应用密度泛函理论,在DZP基组水平上研究了(5,5)型锗纳米管催化的氧还原反应(ORR)的性能以及可能的催化机理.计算结果表明,ORR在锗纳米管上可能经历O_2解离、OOH解离、H_2O_2解离三种可能机理.无论是对哪种机理,整个ORR均遵循四电子反应路径.评估ORR性能的重要中间产物O和OH的吸附能分别为-4.33 eV和-2.21 eV,这与它们在贵金属铂(Pt)上的吸附能非常接近.此外,在GeNT上,整个ORR过程中最后一步生成的H_2O分子的吸附能仅仅为-0.05 eV,比O_2分子的吸附能弱得多,意味着整个ORR催化循环在GeNT上可以顺利更替.因此,联合ORR的反应能量数据和中间产物的吸附数据,可以认为(5,5)型锗纳米管具有类Pt的催化性能.溶剂效应计算结果表明,一些反应中间产物的吸附结构,如O中间体会在很大程度上受到溶剂效应的影响.对所研究的锗纳米管来说,溶剂效应可以促进其催化的ORR进程.
The density functional theory (DFT) was used to study the performance of (5,5) -type germanium nanotubes catalyzed by ORR and the possible catalytic mechanism at the DZP basis. The calculated results show that ORR may be on germanium nanotubes And undergoes the four possible mechanisms of O 2 dissociation, OOH dissociation and H 2 O 2 dissociation, and the ORR of the entire ORR follows the four-electron reaction path regardless of the mechanism.The adsorption energies of O and OH, which are important intermediate products for evaluating the ORR performance, are -4.33 eV and -2.21 eV, which is very close to their adsorption energy on platinum (Pt) In addition, the adsorption energy of H 2 O molecules generated in the last step of the entire ORR process on GeNT is only -0.05 eV, , Indicating that the entire ORR catalytic cycle can be successfully replaced on the GeNT.Thus, it can be considered that the (5,5) -type germanium nanotubes have the Pt-like properties in combination with the reaction energy data of the ORR and the adsorption data of the intermediate product The results of solvent effect show that the adsorption structure of some reaction intermediates, such as O intermediate, will be greatly affected by the solvent effect.For the studied germanium nanotube, the solvent effect can promote its catalytic ORR process.