Theoretical Insights Into Chlorine Evolution Reaction on Cu‐BTC Doped With Transition Metals

ABSTRACT Light‐driven chlorine evolution reaction (CER), with suitable non‐noble metal photocatalysts, is an effective means to replace electrocatalytic CER and alleviate energy crises. Herein, the photocatalytic CER performance of Cu‐BTC, a metal organic framework doped with transition metals (TM), is assessed by density functional theory calculations. The results reveal that as the d ‐electron filling of TM increases, the free energy of chlorine adsorption approaches zero, wherein pristine Cu‐BTC possesses thermodynamic Δ G *Cl close to zero, and CuTM‐BTC with TM of Ni, Pd, and Pt exhibit |Δ G *Cl | less than 0.3 eV, reflecting excellent CER activity. Especially, the bimetallic active sites of CuNi‐BTC and CuPd‐BTC exhibit enormous potentials. Furthermore, the candidates offer the suitable highest occupied molecular orbitals (HOMO), being more negative than the oxidation potential of Cl − /Cl 2 , which is beneficial for the excitation of charge carriers. The electronic structure analysis demonstrates that a good linear relationship is established between the CER overpotentials and the energy levels of HOMO. In the regard, this work sheds lights on the modification of photocatalytic activity via regulation of the energy levels of HOMO.