Pyroelectric Enhanced Catalytic Oxidation: A Universal Strategy for Low-Temperature Gas Phase Catalysis.

Abstract

In the field of gas phase catalysis, reactive oxygen species (ROS) play a crucial role, but how to improve catalytic efficiency and lifetime by forming ROS efficiently and sustainably during the catalytic process is a challenge for high-performance catalysts. Here, a pyroelectric enhanced catalytic oxidation (PECO) strategy is reported that can effectively enhance the catalytic oxidation efficiency and life of the catalyst by constantly generation of ROS. When gaseous pollutants of formaldehyde (HCHO) are catalytically degraded by conductive aerogel catalysts of MnO_x, the HCHO to CO₂ conversion efficiency is increased by ≈300% to 95.33% at a high gas hourly space velocity (GHSV: 600 L g_cat. ^-1·h^-1) using the pyroelectric effect of BaTiO₃, and the efficiency attenuation is less than 3% during the continuous catalytic process of 1200 h. The experimental and theoretical analysis confirm that the pyroelectric effect contributes to improving valence transition of Mn³⁺/Mn⁴⁺ and electron transfer of oxygen-containing molecules thus leading to the continuous formation of ROS. The PECO strategy provides a simple and effective approach for ROS engineering and has broad application prospects in the field of catalysis.