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

Abstract

The development of efficient heterogeneous Fenton catalysts is mainly by "trial-and-error" concept and the factor determining HO activation remains elusive. In this work, we demonstrate that suitable facet exposure to elongate O-O bond in HO is the key parameter determining the Fenton catalyst's activity. CuFeO 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 CuFeO {012} is four times faster than that of CuFeO {110} (0.0408 vs 0.0101 min). In CuFeO {012}-HO 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 HO by electron from CuFeO {012} due to suitable elongation of O-O (1.472 Å) bond length in HO. By contrast, the O-O bond length is elongated from 1.468 to 3.290 Å by CuFeO {110} facet, HO tends to be dissociated into -OH group and passivates {110} facet. Besides, the new formed ≡Fe* on CuFeO {012} facet can accelerate the redox cycle of Cu and Fe species, leading to excellent long-term stability of CuFeO nanoplates.

Effect of Mn doping on the microstructure and magnetic properties of CuFeO2 ceramics

“…As a delafossite compound, multiferroic CuFeO 2 (CFO) has a triangular lattice anti-ferromagnetic (TLA) structure composed of two layers of O 2and one layer of Cu + along the c axis in crystallography [1,2]. Anti-ferromagnetic interaction between iron ions (S = 5/2 and L = 0) causes geometric frustration [3,4]. Without an external magnetic field, the magnetic phase of CFO changes from a paramagnetic (PM) phase to a partially disordered (PD) incommensurate phase at the transition temperature T N1 = 14 K with a 3 R m space group lattice structure, and then to a foursublattice (4SL) state at the transition temperature T N2 = 11 K with a monoclinic C2/m structure.…”

Efficient Fe/CuFeO2/rGO nanocomposite catalyst for electro‐Fenton degradation of organic pollutant: Preparation, characterization and optimization

“…The other reaction that Fe 3+ attends is Equation . This reaction produces Fe 2+ , which can react with H 2 O 2 to make more hydroxyl radical (Equation ) The utilization of Fe/CuFeO 2 /rGO as the catalyst in the EF reaction for degradation of catechol increases the pollutant removal (99%).…”

Doping‐Dependent Phase Fractions in Hydrothermally Synthesized Mn‐Doped CuFeO2

“…Depending on the stacking orientation of the double layers consisting of edge‐sharing B III O 6 octahedra and of triangularly arranged A I layers, delafossite exists in a rhombohedral (R3) and hexagonal (2H) form with and space group, respectively. [ 1 ] is a semiconductor with an indirect optical bandgap at about 1.3 eV [ 2 ] and other favorable properties, which drive research into its application as an active anode material for lithium‐ion and sodium‐ion batteries, [ 3 ] for thermoelectric energy generation, [ 4,5 ] and as a catalyst for various catalytic approaches ranging from pollutant degradation to CO 2 conversion and solar energy conversion [ 6–9 ] among others. Besides, it is also of fundamental interest thanks to its magnetic properties and structures at low temperatures.…”