Presentation Information
[2P02]First-Principles and Experimental Study of Arsenic Adsorption on Cu and CuO in Hot Spring Water
*Yuiri Mizukoshi1, Rina Inuzuka, Takahiro Yamamoto1 (1. Department of Physics, Tokyo University of Science)
Access to safe drinking water remains a global issue due to contamination by toxic substances such as arsenic (As), especially in groundwater sources like hot springs. Copper (Cu) and copper oxide (CuO) have been identified as promising adsorbents for As, and carbon nanotubes (CNTs) offer high surface areas for enhanced adsorption. This study aims to develop CNT/Cu hybrid materials by first investigating how Cu's surface oxidation affects As adsorption. DFT calculations were performed for meta-arsenite (HAsO2) on Cu and CuO surfaces. Adsorption energies were -1.82 eV for Cu and -2.92 eV for CuO, indicating strong adsorption on both, with CuO showing higher affinity. However, SEM-EDS analysis of Cu plates immersed in hot spring water for one week revealed only 0.35% As on the surface. This mismatch suggests that coexisting ions in real water inhibit adsorption. To address this, we are applying the Nudged Elastic Band (NEB) method to evaluate kinetic barriers. These insights will guide the design of efficient, selective adsorbents for safe water treatment.