Wide-temperature NO_x removal enabled by synergistic atomically dispersed CeV dual sites: Activation of the...

Commercial V-W/TiO₂ catalysts are extensively applied for NO_x emission control in coal-fired power plants. However, their limited operating temperature range and low active site utilisation significantly restrict NO_x removal efficiency, particularly during boiler load fluctuations. This study introduces atomically dispersed Ce-V/TiO₂ catalysts synthesised using a dual-site coordination strategy, enhancing active site dispersion. This method addresses the limitations of low active site turnover frequency (TOF) and high energy barriers in rate-determining steps, resulting in an extended operating temperature range and improved NO_x removal efficiency. Under identical conditions, Ce-V/TiO₂ achieved 90 % NO_x conversion from 290 to 450 °C, a substantial increase over the commercial catalyst (365-425 °C). Additionally, Ce-V/TiO₂ exhibited a TOF of 3.58 × 10^-3 s^-1, 1.52 times higher than the commercial catalyst. Density functional theory (DFT) analysis demonstrated that CeV synergy accelerates the Eley-Rideal rate-determining step by lowering the activation energy for NH₃ dissociation into -NH₂, and reduces the energy barrier for -NHNO intermediate formation in the Langmuir-Hinshelwood pathway. This work overcomes poor low-temperature activity by leveraging CeV synergy, offering a strategy for efficient NO_x removal across a broad temperature range with selective catalytic reduction catalysts.