First-Principles\nInsights into Electrochemical Methanol\nOxidation on Boron-Doped Nickel Clusters Supported by Graphene under\nAlkaline Conditions

Methanol\noxidation is essential for efficient methanol utilization\nin hydrogen production and direct methanol fuel cells. This study\nemploys density functional theory (DFT) calculations to explore methanol\noxidation reactions on graphene-supported Ni<sub>10</sub> and boron-doped\nNi<sub>10</sub>B clusters. The Ni<sub>10</sub>-gra model in an acidic\nenvironment demonstrates effective methanol capture with an adsorption\nenergy of −0.48 eV and deprotonates from CO* species with an\nonset potential of 0.14 V, progressing the CH<sub>2</sub>O* to CHO*\nstep. The primary energy barrier is the conversion of CO* to COOH*\nwith an activation onset potential of 0.38 V, while a strong CO<sub>2</sub> adsorption energy of −0.85 eV complicates the product\nrelease. Boron doping in Ni<sub>10</sub>B-gra slightly increases the\nonset potential to 0.51 V for the same potential-determining step\nbut significantly reduces the adsorption energy of CO<sub>2</sub> to\n0.35 eV. Under alkaline conditions, the methanol oxidation reaction\nis examined on preadsorbed OH* models, including 1–4OH*Ni<sub>10</sub>-gra and 1–4OH*Ni<sub>10</sub>B-gra models. The presence\nof OH* groups increases the chemical potential of COOH* on 1–4OH*Ni<sub>10</sub>-gra, but this effect is moderated on 0–3OH*Ni<sub>10</sub>B-gra. Additionally, boron doping in 1–4OH*Ni<sub>10</sub>B-gra increases the chemical potential of CO*, resulting\nin an onset potential for methanol oxidation reaction (MOR) ranging\nfrom 0.42 to 0.65 V, which is better than the 0.55–1.07 V range\nobserved for 1–4OHNi<sub>10</sub>-gra. Overall, boron doping\nsignificantly enhances the catalytic performance of Ni clusters for\nMOR under alkaline conditions by adjusting the chemical potentials\nof CO* and COOH*, leading to lower onset potentials and improved electrocatalytic\nperformance.