CVD-grown molybdenum boride (MBene) for high-performance supercapacitors

Abstract

In this study, Mo₂B, an important member of the MBenes family, was successfully synthesized as single-phase, homogeneous and thickness-controlled thin films on a copper substrate by chemical vapor deposition (CVD). The structural and morphological properties of the material were characterized in detail by SEM, EDX, XRD, Raman and AFM techniques, and the results showed the high crystal quality and smooth surface structure of the films. AFM analysis revealed a thickness of approximately 45 nm and an average crystallite size of 43.7 nm. In the electrochemical performance evaluations, high specific metric capacitance (1227.6 F g⁻¹), specific area capacitance (33.15 mF cm⁻²), specific power density (1704 W kg⁻¹) and specific energy density (6138 Wh kg⁻¹) were obtained using the Mo₂B supercapacitor electrode. In supercapacitor performance tests at a current density of 15 A g⁻¹, 99% capacity retention over 20 000 cycles indicates high energy efficiency and longevity. These results suggest that Mo₂B is a strong candidate for energy storage applications. As a result, it has been demonstrated that molybdenum boride produced by the CVD method provides both cost advantages and scalability in terms of production and high performance in supercapacitors. This study presents an important innovation in the field by showing the performance of CVD-grown Mo₂B materials in supercapacitor applications for the first time in the literature. It also provides an important reference for the applicability of Mo₂B not only for supercapacitors but also in advanced technology fields such as sensors and nanoelectronic devices.