Septia Eka Marsha Putra, Indah Gumala Andirasdini, Fahdzi Muttaqien
Understanding water's role in stabilizing adsorbates on metal surfaces is key to improving catalytic systems. Using density functional theory (DFT), we investigated the co-adsorption of formate (HCOO) and water on Cu(111). Three formate geometries were evaluated: bidentate (Eads=−0.82eV), monodentate via hydrogen (Eads=−0.27eV), and monodentate via oxygen (Eads=−0.24eV), with bidentate being the most stable. Co-adsorption with H2O enhances stability: bidentate formate shows interaction energies of Eint=−0.32eV (one H2O) and −0.53eV (two H2O), while monodentate forms show much weaker stabilization. The approximate 0.20 eV increase in stability per added water molecule arises mainly from hydrogen bonding between water and formate oxygens. The enhanced stability in the two-water case arises from cooperative effects, where one H2O forms a hydrogen bond with the formate oxygen and the second H2O interacts weakly with the Cu surface. These results highlight water's key role in stabilizing bidentate formate on Cu surfaces, reinforcing its thermodynamic preference in aqueous conditions. © 2025 Elsevier B.V.
Department of Engineering Physics, Institut Teknologi Sumatera, Jl. Terusan Ryacudu, Way Huwi, Jati Agung, South Lampung, 35365, Indonesia; Department of Actuarial Science, Institut Teknologi Sumatera, Jl. Terusan Ryacudu, Way Huwi, Jati Agung, South Lampung, 35365, Indonesia; Master Program in Computational Science, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha No. 10, West Java, Bandung, 40132, Indonesia; Instrumentation and Computational Physics Research Group, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha No. 10, West Java, Bandung, 40132, Indonesia