Revealing the equilibrium relationship between lattice oxygen mobility and styrene removal: Sources of adsorption and activation by in situ experiments

Abstract

Copper-manganese composite oxides have been extensively researched for the catalytic oxidation of volatile organic compounds (VOCs), but there is little understanding of the adsorption and activation of VOCs over these compounds. In this work, a series of amorphous Cu-Mn binary oxides with varying Cu/Mn ratios were prepared to explore their catalytic performance and the species involved in the adsorption and activation of styrene (C8H8). It was found that Cu1Mn5Ox demonstrated better catalytic activity among the four samples, better stability and water resistance due to the presence of more structural flaws, weaker Mn-O bonds and more surface lattice oxygen species. In situ designed experiments showed that the adsorbed oxygen species, O2, lattice oxygen, and copper species all played roles in the adsorption and activation of C8H8 at low temperatures. The degradation route for C8H8 was revealed by in situ DRIFTS, and benzoic acid decomposition was identified as the rate-limiting step of C8H8 degradation. This work provides a novel technique for regulating the synergistic adsorption and catalytic ability of amorphous bimetallic oxides to remove VOCs.