Tertiary amine-functionalized Co(II) porphyrin to enhance the electrochemical CO2 reduction activity

Theoretical Understanding of Potential-Dependent Electrocatalytic CO2RR and Competition with HER upon Cobalt Single Atom Supported by Phthalocyanine Monolayer

“…Thus, these researchers took physically adsorbed CO 2 as the reaction intermediate, 8,17,41,42 or they even simply skipped the CO 2 adsorption step. 3,7,9,11 We have tried to use the CHE model to calculate the adsorption of CO 2 on Co-Pc and obtained the same results: two initial configurations were considered, neither of which could form a CO 2 chemisorption configuration, but only physisorption (Figure S7). However, by using GC-DFT with a more negative potential, CO 2 molecules could chemisorb upon Co-Pc with a deformed structure (Figure 2a).…”

“…Previous CHE model based computational results indicated that CO 2 molecules could hardly be chemisorbed upon numerous SACs, including Co-Pc, and could not be deformed. Thus, these researchers took physically adsorbed CO 2 as the reaction intermediate, ,,, or they even simply skipped the CO 2 adsorption step. ,,, We have tried to use the CHE model to calculate the adsorption of CO 2 on Co-Pc and obtained the same results: two initial configurations were considered, neither of which could form a CO 2 chemisorption configuration, but only physisorption (Figure S7).…”

“…After identified the physical meaning of the ΔΩ­(eV)– U (V) slope, we also calculated the HER competition upon other reported heterogeneous catalysts, ,,, including Cu(211), Ag(110), iron doped in 2D phthalocyanine (Fe-Pc), cobalt in 2D porphyrin (Co–Pr), and cobalt doped in nitrogen-doped (4N) graphene (Co-Gra@N4), shown in Figure b and Figure S9. Generally, larger electron transfer can be observed in *H formation (larger (ΔΩ– U ) slope) than CO 2 chemisorption; thus, these catalysts will show the coverage crossover as discussed above, HER will also completely suppress CO 2 RR at high applied potential, the current dilemma of realization of industrial electrocatalytic CO 2 RR.…”

“…Experimentally, the onset potential of CO 2 RR upon Co-Pc SACs is about −0.4 V vs. RHE (reversible hydrogen electrode); meanwhile, high Faradaic efficiency (maximum exceeding 95%) and considerable current density for CO product could be observed at −0.5 to −0.9 V vs. RHE. When the applied potential becomes lower than −0.9 V, the Faradaic efficiency and current density of CO will rapidly decrease, while those of H 2 increase tremendously, − which could be usually observed on other heterogeneous catalysts. − This is also the main reason for the inadequate CO 2 RR current density for current industrial applications.…”

Variable frequency microwave induced CO2 Boudouard reaction over biochar

“…Notably, electrochemical reduction of CO 2 is acknowledged as a clean and sustainable technology (Jin et al 2021). Xuan et al (2022) innovatively designed a tertiary amine-functionalized Co(II) porphyrin (2NPorCo) catalyst for electrochemical CO 2 reduction, achieving a remarkable CO Faraday efficiency of 96.7%, coupled with a turnover rate of 5433 h −1 . However, the process necessitates a complex catalytic system, and its energy efficiency is constrained by the substantial overpotential required for CO 2 activation.…”