Electrocatalytic valorization of waste sulfur-containing species

Sulfur-containing wastes are typical pollutants generated from oil and gas extraction, petroleum refining, and fossil fuel combustion, with annual global emissions reaching tens of millions of tons. Traditional treatment technologies rely on end-of-pipe control, suffering from high energy consumption, substantial carbon emissions, severe secondary pollution, and low resource utilization efficiency. Electrocatalytic conversion driven by renewable electricity enables the directional valorization of sulfur-containing pollutants under mild conditions, providing an alternative route for the green upgrading of sulfur resources. This review systematically summarizes the research progress in electrocatalytic valorization technologies for waste sulfur-containing species. Starting from the fundamental reaction principles, we elaborate the electrocatalytic conversion routes, reaction mechanisms, catalyst design, and system optimization strategies for four typical sulfur-containing substrates, including inorganic sulfides, sulfur oxides, organosulfur wastes, and metal sulfide minerals. It highlights the core technological innovations of direct interfacial electrocatalysis, redox mediator-mediated indirect electrocatalysis, and paired electrolysis. Moreover, the key challenges in anti-sulfur-passivation electrodes, reactor scale-up, reaction process design, and adaptation to complex industrial systems are outlined, and future perspectives are proposed. This review aims to provide theoretical and technical guidance for the green and low-carbon valorization of industrial sulfur-containing pollutants.