Interface-Engineered AgCoAc on Ti3C2T x MXene as a Bifunctional Electrocatalyst for Advancing CO2 Utilization and Oxygen Evolution

Abstract

The escalating global demand for renewable energy sources and chemicals necessitates sustainable and resource-conscious production protocols that address future demands with a minimal environmental impact. The current study presents the viability of the AgCoAc@Ti3C2Tx-based catalyst for the CO2 fixation and oxygen evolution reaction (OER) reactions at mild operational parameters. Unlike previously reported MXene-based electrocatalysts, this work integrates a controlled electrodeposition methodology to create a synergistic AgCoAc active interface directly on a conductive MXene support. This tailored architecture leads to dual functionality, demonstrating enhanced performance in both electrocarboxylation and the OER, which has not been explored in similar systems. The multilayered Ti3C2Tx, having a large electroactive area, improves the physicochemical properties and charge-transfer pathways of AgCoAc moieties, restricting particle aggregation and stabilizing the composite structure. Meanwhile, AgCoAc anchored on Ti3C2Tx amplifies its conductive properties and provides dual metal coordination sites, elevating the catalyst efficiency for the electrocatalytic process. Electrocarboxylation of benzyl bromide with CO2 was carried out in a single-chamber cell comprising tetrabutylammonium bromide/acetonitrile (TBABr/ACN) as the electrolytic medium to generate phenylacetic acid (PAA). This synergy in AgCoAc@Ti3C2Tx yielded a maximum of 70% PAA at a current density of 50 mA cm–2 at room temperature. The performance of AgCoAc@Ti3C2Tx was further investigated for the OER in 1 M KOH, which showcased a low overpotential of 251 mV at 10 mA cm–2 with a Tafel slope of 93 mV dec–1, validating excellent OER performance. Hence, the developed protocol provides a facile catalyst preparation strategy for the dual-purpose multimetallic AgCoAc@Ti3C2Tx composite, which showcased admirable outcomes for electrocarboxylation as well as the OER.