As important chemical products, benzaldehyde or benzoic acid is widely used in perfumes, dyes, and pharmaceutical intermediates . At present, the preparation methods of benzaldehyde mainly include the oxidation of benzyl alcohol, the oxidation of toluene, and the hydrolysis of benzyl chloride . Among them, benzyl alcohol oxidation is widely used because of its low cost. Commonly used oxidants or catalysts for the oxidation of benzyl alcohol include chromic acid, dichromate, permanganate, and precious metal catalysts . However, these oxidation methods have some disadvantages. For example, the waste generated from the used oxidant would pollute the environment and is prone to excessive oxidation. So, it is very important and necessary to find a green oxidant.