Using non-combustion explosion in H ₂ O/DMF to synthesize 3D Structure of ultrathin Bi nanofilm with high catalytic activity for p-nitrophenol reduction

Abstract The synthesis of inorganic micro-/nano-materials by dry combustion is somewhat dangerous since it is performed under high temperature. The ultrathin Bi nanofilms with 3D structures were synthesized using a safe approach of non-combustion explosion in H ₂ O/DMF solution at room temperature and atmospheric pressure. The violent reaction between H ₂ O ₂ and NH ₃ · H ₂ O resulted in a non-combustion explosion due to the fast evolution of gases. Then under high temperature and high pressure during solvothermal process, the further slight explosion occurred where the oxygen-containing molecules of H ₂ O ₂ and NO ₃ ⁻ acted as oxidants, while the hydrogen-containing molecules of NaBH ₄ , NH ₃ · H ₂ O and DMF acted as reductants. The release of gases was accompanied with Bi ^III reduction by NaBH ₄ . The 3D structure of ultrathin Bi nanofilms with many void spaces formed due to the explosive force and foams from the sharp liberation of gases. Such ultrathin Bi nanofilms with 3D structure exhibited outstanding catalytic activity for p-nitrophenol hydrogenation which is important to treat the environmental pollution from p-nitrophenol discharge. Within only several seconds p-nitrophenol hydrogenation was completed without delay. The non-combustion explosion exhibits potential applications for the synthesis of 3D ultrathin film materials as high efficient catalysts.