Facial deposition of Prussian blue on thermochemically functionalized carbon cloth: An efficient cesium recovery via electrochemically assisted ion–exchange process

An electrochemically assisted ion-exchange method using iron(III) hexacyanoferrate(II) (Prussian blue, PB) on a chemically treated carbon cloth (ACC) substrate presents a promising approach for the adsorption of cesium ions (Cs+) from contaminated water, due to its ease of operation, superior ion-exchange capability, rapid removal efficiency, and high selectivity. In this study, we improved the functionality of commercial carbon cloth (CC) using a simple yet effective acid rinsing under maintained thermal conditions, which embodied its high wettability and homogenous electrochemical deposition of PB. The PB-deposited ACC electrodes exhibited high charge transfer, fast adsorption, improved capacity, selectivity for Cs+ ions, and improved cycling performance. To the best of our knowledge, PB deposited on ACC fabric network demonstrates superior electrochemical adsorption capacity. Within 3 h of the adsorption kinetics, the PB-deposited ACC electrode shows a 1173 mg g–1 Cs+ adsorption capacity. It is the highest ever reported adsorption capacity for PB based materials with an above 90% cycling efficiency for five consecutive cycles, which is promising for real-world Cs+ separation, water distillation, and recovery. This study provides a new avenue for designing durable and high-performance electrodes for electrochemically assisted ion-exchange systems. These results confirm that the initial hydrophobic nature of pristine CC is substantially modified by acid treatment at 60 °C, which improves the surface wetting properties crucial for electrochemical performance and PB deposition.