Verma Manju, Deshpande Parag A
Quantum and Molecular Engineering Laboratory, Department of Chemical Engineering, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India), Tel: (+91) 3222-283916.
Chemphyschem. 2016 Oct 5;17(19):3120-3128. doi: 10.1002/cphc.201600649. Epub 2016 Aug 17.
The biomimetic CO hydration activity of Ru/Rh-doped fullerenes was revealed by using density functional theory calculations. The mechanism of CO hydration on the proposed heterofullerenes followed the mechanistic action of α-carbonic anhydrases, and consisted of the adsorption and deprotonation of H O, CO interaction with hydroxyl groups, CO bending, and proton transfer to give the HCO-3 product. Free-energy landscapes for the reaction showed the catalysts to be active for the reaction. H O adsorption over the catalysts was exergonic whereas CO adsorption over the catalyst-OH complex was observed to be an endergonic process. Intramolecular proton transfer resulting in the final product, HCO-3 , was found to be the rate-limiting step for the reaction on C N M (M=Ru/Rh), whereas H O dissociation was found to be the rate-limiting step for the reaction on C M (M=Ru/Rh). C N M catalysts were found to be superior to C M catalysts for biomimetic CO hydration, as indicated by the free-energy landscapes and energy requirements.
通过密度泛函理论计算揭示了钌/铑掺杂富勒烯的仿生一氧化碳水合活性。所提出的杂富勒烯上一氧化碳水合的机理遵循α-碳酸酐酶的作用机制，包括水的吸附和去质子化、一氧化碳与羟基的相互作用、一氧化碳弯曲以及质子转移以生成碳酸氢根产物。反应的自由能曲线表明催化剂对该反应具有活性。水在催化剂上的吸附是放能的，而一氧化碳在催化剂-羟基络合物上的吸附是吸能过程。导致最终产物碳酸氢根的分子内质子转移被发现是在CₙM（M = Ru/Rh）上反应的速率限制步骤，而水的解离被发现是在Cₘ（M = Ru/Rh）上反应的速率限制步骤。自由能曲线和能量需求表明，在仿生一氧化碳水合方面，CₙM催化剂优于Cₘ催化剂。
