Catalytic Pollutant Upgrading to Dual‐Asymmetric MnO <sub>2</sub> @polymer Nanotubes as Self‐Propelled and Controlled Micromotors for H <sub>2</sub> O <sub>2</sub> Decomposition
Yangyang Yang, Kunsheng Hu, Zhong‐Shuai Zhu, Yu Yao, Panpan Zhang, Peng Zhou, Pengwei Huo, Xiaoguang Duan, Hongqi Sun, Shaobin Wang
Abstract
Abstract Industrial and disinfection wastewater typically contains high levels of organic pollutants and residue hydrogen peroxide, which have caused environmental concerns. In this work, dual‐asymmetric MnO 2 @polymer microreactors are synthesized via pollutant polymerization for self‐driven and controlled H 2 O 2 decomposition. A hollow and asymmetric MnO 2 nanotube is derived from MnO 2 nanorods by selective acid etching and then coated by a polymeric layer from an aqueous phenolic pollutant via catalytic peroxymonosulfate (PMS)‐induced polymerization. The evolution of particle‐like polymers is controlled by solution pH, molar ratios of PMS/phenol, and reaction duration. The polymer‐covered MnO 2 tubing‐structured micromotors presented a controlled motion velocity, due to the reverse torque driven by the O 2 bubbles from H 2 O 2 decomposition in the inner tunnels. In addition, the partially coated polymeric layer can regulate the exposure and population of Mn active sites to control the H 2 O 2 decomposition rate, thus avoiding violent motions and massive heat caused by vigorous H 2 O 2 decomposition. The microreactors can maintain the function of mobility in an ultra‐low H 2 O 2 environment (<0.31 wt.%). This work provides a new strategy for the transformation of micropollutants to functional polymer‐based microreactors for safe and controlled hydrogen peroxide decomposition for environmental remediation.