Dr Robert Lawrence
Academic and research departmentsFaculty of Engineering and Physical Sciences.
The dissociation of NO on metal-free graphene was studied using density functional theory (DFT). The effect of heteroatomic substitution of boron and nitrogen on the activity of the single vacancy was explored. While the doping did not affect the NO chemisorption barrier, it was found that the dissociation step was activated by B (down to 4 meV) but deactivated by N (up to 2.42 eV). In addition to the nature of the dopant, the location of the heteroatom with respect to the single vacancy site had an even stronger influence on the reactivity of graphene, reducing the barrier for dissociation fourfold.
Electrochemical carbon dioxide (CO2) reduction reaction (CO2RR) is an attractive approach to deal with the excessive emission of CO2 and to produce valuable fuels and chemicals in a carbon-neutral way. Many efforts have been devoted to boost the activity and selectivity of high-value multicarbon products (C2+) on Cu-based electrocatalysts. However, Cu-based CO2RR electrocatalysts suffer from poor catalytic stability mainly due to the structural degradation and loss of active species under CO2RR condition. To date, most reported Cu-based electrocatalysts present stabilities over dozens of hours, which limits the advance of Cu-based electrocatalysts for CO2RR. Here, a porous chlorine-doped Cu electrocatalyst is reported and exhibits high C2+ Faradaic efficiency (FE) of 53.8 % at-1.00 V versus reversible hydrogen electrode (VRHE). Importantly, the catalyst exhibited an outstanding catalytic stability in long-term electrocatalysis over 240 hours. Experimental results show that the chlorine-induced stable cationic Cu 0-Cu + species and the well-preserved structure with abundant active sites are found to be critical to maintain the high FE of C2+ in the long-term run of electrochemical CO2 reduction.