A scalable, tunable, electrochemical dissolution method for anchoring single-atom catalysts on 2d sheets of molybdenum disulfide

Abstract

Single-atom catalysts (SACs), featuring isolated metal atoms dispersed on supporting materials, are driving sustainable catalysis by offering superior catalytic properties compared to bulk metals. These SACs enhance metal utilization efficiency, crucial for applications in electrochemical energy conversion, heterogeneous catalysis, and high-sensitivity sensing, particularly in reducing reliance on expensive noble metals. Traditional SAC synthesis methods, however, face scalability challenges and limitations in atomic loading, often leading to the formation of nanoclusters at higher metal concentrations. To address these challenges, this study explores an electrochemical dissolution strategy for SAC synthesis. The approach involves the accelerated cathodic or anodic dissolution of thin metal films, utilizing their fine grain structure and residual stress to generate metal ions that are anchored at defect sites on 2D MoS₂-coated laser-scribed graphene electrodes (LSGEs). This method achieves controlled deposition of Pt, Au, and Cu SACs with uniform atomic dispersion and tunable loading contents. Comprehensive characterization, coupled with density functional theory simulations (DFT), confirms the absence of nanoparticle agglomeration and reveals the coordination environment of the SACs. Lastly, we demonstrate precise discrimination of uric acid (UA) in the presence of dopamine (DA) and ascorbic acid (AA), despite their overlapping redox peaks in a complex matrix of urine, showcasing the method’s potential for scalable SAC production and high-sensitivity sensing applications.