“…As an n-type wide-band semiconductor (Eg = 3.6 eV, 300 K), it is widely used in many areas such as gas sensor [1,2], electrode material [3,4], solar cells [5,6], and catalysts [7]. For these key functional applications, it has been prepared through a wide variety of synthetic approaches such as solvothermal method, spray pyrolysis, sputtering, solution-phase growth, vapor-liquid-solid (VLS) growth, and molten salt synthesis, among others [8][9][10][11][12][13].…”