Plasma-catalytic oxidation of chlorobenzene over Mn-doped BaTiO3: Unveiling plasma-enhanced lattice oxygen dynamics

Chlorinated volatile organic compounds (CVOCs) such as chlorobenzene (CB) are highly stable and toxic pollutants that are difficult to degrade under mild conditions. Conventional thermal catalytic oxidation requires elevated temperatures (200–400 °C), which not only limits its industrial applicability but also risks the formation of secondary chlorinated by-products. Herein, we report a plasma-catalytic oxidation system employing Mn-doped barium titanate (BaTi(Mn)O x ), synthesized via a solvothermal route, for efficient low-temperature CB oxidation. The incorporation of a small amount of Mn (0.97 wt%) into BaTiO 3 significantly enhanced catalytic performance, achieving 97.2% CB conversion and 68.3% CO x selectivity at an exceptionally low specific energy input (< 18 J/L). Comprehensive characterizations revealed that Mn doping promotes electron transfer between Mn and Ti, resulting in the formation of abundant oxygen vacancies (O v ) and chemisorbed oxygen species with high redox activity. Plasma-catalyst synergy further activated lattice oxygen species, enhancing oxygen mobility and sustaining deep oxidation of intermediates. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) identified key reaction intermediates, including p- and o-benzoquinones, and demonstrated that their complete oxidation to maleic acid and conjugated dienes is facilitated by the dynamic interaction between surface (O sur ) and lattice oxygen (O lat ). These findings provide new insight into the plasma-induced activation mechanism of perovskite catalysts and offer a rational design strategy for high-performance plasma-catalytic systems for low-temperature oxidation of CVOCs.