Fig. 5: Theoretical investigation of the UOR on the atomically isolated asymmetric Ni–O–Ti sites.
From: Highly selective urea electrooxidation coupled with efficient hydrogen evolution
a The adsorption energies of urea on asymmetric Ni–O–Ti sites and symmetric Ni–O–Ni sites in different configurations. Charge density difference of urea adsorbed on (b) asymmetric Ni–O–Ti sites and (c) symmetric Ni–O–Ni sites. The yellow and blue iso-surfaces with an iso-value of 0.004 a.u. represent spatial charge accumulation and depletion, respectively. d The COHP analysis of C–N bond in the free and adsorbed urea on asymmetric Ni–O–Ti and symmetric Ni–O–Ni sites. e The UOR process diagram and Gibbs free energy change on asymmetric Ni–O–Ti and symmetric Ni–O–Ni sites.
