Tailoring hydrophobic-aerophilic microenvironment for robust electrochemical ozone production

Improving the activity and durability of electrocatalysts in electrochemical ozone production (EOP) processes is essential for efficient ozone generation. Herein, superhydrophallic cubic-Pb3O4 particles were encapsulated in a Si-CH3 functionalized SiO2 layer to obtain superhydrophobic cubic-Pb3O4@SiO2. Experimental and theoretical results indicate that the presence of Si-CH3 groups of cubic-Pb3O4@SiO2 confers a hydrophobic-aerophilic microenvironment, which increases the diffusion of reactive molecules across the electrode and oxygen adsorption, ultimately leading to ozone enrichment. Besides, due to the excellent protective effect of the SiO2 layer, the cubic-Pb3O4@SiO2 based membrane electrode assembly (MEA) electrolyzer achieved a stable EOP operation of 400 h in neutral medium at the current density of 1A cm−2 (Faraday efficiency: 21%, yield: 633 mg h−1 g-1catalyst). Furthermore, the combination of the MEA electrolyzer with the continuous flow process can achieve efficient degradation of dyes and pesticides. This work provides novel insights into tuning electrocatalyst microenvironments for efficient EOP process.