Single-crystalline WSe₂ nanoflakes as efficient electrocatalysts

This study presents a novel single molecular source with covalently bonded ligand systems, featuring pre-existing W-Se bonds, for direct synthesis of single crystalline flakes of 2D tungsten diselenide (WSe2). Synthesis and structural characterization of [W{(SeC2H4)(2)NMe}(2)] expand the class of single- source precursors for metal sulfides and selenides of general formula [M-IV{(XC2H4)(2)NMe}(2)] (M-IV = Ti, Zr, Hf, Mo, W, Sn; X = S, Se). Comprehensive analysis including NMR, elemental analysis, and single crystal X-ray diffraction, provide insights into structural characteristics of [W{(SeC2H4)(2)NMe}(2)] in solution and solid state. Microwave-assisted solvothermal decomposition at 300 degrees C for 15 minutes yielded highly crystalline WSe2 flakes, confirmed by XRD, SEM, EDS, and TEM analyses. Reduced reaction time under mild conditions enables reproducible generation of layered 2D WSe2 materials for large-scale applications. Electrochemical studies reveal increased electrocatalytic activity, attributed to enhanced electrochemical surface area (ECSA, 67.3 cm(2)) observed in the as-prepared WSe2 flower-like nanostructures.