Energy engineers are focusing on technologies like electrolyzers to generate and store electrical power sustainably. PEM electrolyzers have advantages over alkaline ones but require ultrapure water to prevent degradation. Researchers have developed a strategy to enhance catalysts for PEM electrolyzers, enabling them to operate with impure water. By introducing Brønsted acid oxides onto cathodes, a strongly acidic microenvironment is created, boosting hydrogen production and extending the device's lifetime. This breakthrough allows PEM electrolyzers to perform steadily in impure water for more than 3,000 hours, comparable to those using pure water. The team's findings open new possibilities for designing reliable PEM electrolyzers that can function with lower-purity water, reducing costs and simplifying deployment. Future advancements in this field could leverage this research to develop more efficient electrolyzers for hydrogen production in real-world applications.