The spatiotemporal effects of electrification on China’s synergistic pollution and carbon reduction efficiency

China’s dual objectives of “Beautiful China” and “Carbon Neutrality” necessitate a synergistic approach to reducing air pollution and carbon emissions. Analyzing the spatiotemporal dynamics of the Efficiency of Synergistic Air Pollution and Carbon Emissions Reduction (ESACR) and its influencing factors, particularly electrification, is critical for enhancing this synergy. This study utilizes provincial-level data from 2000 to 2021, employing the super-efficiency Slack-Based model to measure China’s ESACR. It then integrates Exploratory Spatial Data Analysis, Spatial Econometric Models, and Geographically and Temporally Weighted Regression (GTWR) models to uncover the spatiotemporal evolution of ESACR and dissect the influence of electrification. The results show that the overall ESACR remains relatively low, indicating substantial room for improvement, with a pronounced decreasing trend from East to West. Meanwhile, the positive effect of electrification on ESACR demonstrates significant spatial heterogeneity, being most effective in coastal and certain western provinces. Therefore, effectively unlocking China’s synergistic pollution and carbon reduction potential requires a multi-tiered policy framework that implements differentiated regional electrification strategies, fosters cross-regional system coordination, and integrates electrification with complementary policies on energy efficiency and industrial structure.