Catalytic degradation of ethyl acetate at room temperature over Ni/NAC monolithic catalyst

Ethyl acetate, a typical oxygen-containing volatile organic compounds (OVOCs) pollutant with a pungent odor and low toxicity, is still a great challenge to catalyze degradation at room temperature. Here, nitrogen-doped activated carbon loading Ni monolithic catalysts prepared by the one-pot impregnation method at an annealing temperature of 900°C (Ni/NAC-900) achieves the 95% removal of ethyl acetate and 67.15% CO 2 selectivity within 58.5 h at 25°C. The result of XRD proves the monolithic catalysts contains Ni single atoms and Ni NPs, of which the Ni single atoms accounts for 92% of the total Ni elements. The XAFs characterization results shows that the active site structure of Ni single atoms is NiN 4 C 2 coordination structure. Hydroxyl radicals (·OH) converted by O 2 and H 2 O in the air on the atomically dispersed NiN 4 C 2 catalytic centers results in the breakage of the C-O bond and C-C bond, which eventually causes the oxidation of ethyl acetate to CO 2 and H 2 O. The findings provide fresh insights into the degradation of ethyl acetate with high efficiency, low consumption and in a safe manner. • A atomically dispersed Ni monolithic catalyst achieved 100% removal of ethyl acetate under mild conditions of 101.3 kPa and 25 ℃. • The catalyst generated oxygen vacancies that activated hydroxyl radicals (·OH). • The NiN4C2 structure served as the active site structure of Ni single atoms. • The N element greatly promoted the uniform dispersion of Ni and better electron transfer on the surface of AC carrier.