Surface Facet of CuFeO2 Nanocatalyst: A Key Parameter for H2O2 Activation in Fenton-Like Reaction and Organic Pollutant Degradation

The development of efficient heterogeneous Fenton catalysts is mainly by “trial-and-error” concept and the factor determining H2O2 activation remains elusive. In this work, we demonstrate that suitable facet exposure to elongate O–O bond in H2O2 is the key parameter determining the Fenton catalyst’s activity. CuFeO2 nanocubes and nanoplates with different surface facets of {110} and {012} are used to compare the effect of exposed facets on Fenton activity. The results indicate that ofloxacin (OFX) degradation rate by CuFeO2 {012} is four times faster than that of CuFeO2 {110} (0.0408 vs 0.0101 min–1). In CuFeO2 {012}-H2O2 system, OFX is completely removed at a pH range 3.2–10.1. The experimental results and theoretical simulations show that •OH is preferentially formed from the reduction of absorbed H2O2 by electron from CuFeO2 {012} due to suitable elongation of O–O (1.472 A) bond length in H2O2. By contrast, the O–O bond length is elongated from 1.468 to 3.290 A by CuFeO2 {110} facet, H2O2 tends to be d...