The impact of digital economy on industrial carbon emission efficiency at the city level in China: Gravity movement trajectories and driving mechanisms

Can the digital economy be a key driver of China's industrial green and low-carbon transformation, promoting the growth of urban industrial economy and reducing carbon emissions to achieve a "win-win" development? The study measured industrial carbon emission efficiency (ICEE), analyzed the spatiotemporal center of gravity movement, and investigated the nonlinear and spatial spillover effects of digital economy on ICEE using panel data based on 270 cities from 2005 to 2020 through the super-efficient model, threshold effects and spatial econometric model. The results were as follows: The ICEE of Chinese cities has generally improved over time, with its center of gravity shifting from west to east, contrary to the trajectory of industrial carbon emissions. The effect of digital economy on ICEE presented an "N" shape of increasing (0.240), decreasing (-0.037), then increasing (0.145), rather than a simple inverted "U" shape. When green technology innovation was the threshold variable, the effect on ICEE exhibited a "U" shape of inhibition followed by promotion (-0.185 to 0.345) rather than a direct positive effect. The digital economy enhanced the ICEE of local cities (0.118) and generated positive spatial spillover effects (0.179) in neighboring cities. However, the impact of digital economy exhibited regional heterogeneity, with a radiating effect (0.117) on neighboring cities in the eastern region and an opposite "siphon effect" (-0.330, -0.174) on neighboring cities in the central and western regions. It is crucial to utilize digital technology sharing advanced industrial technology and low-carbon concepts to transcend geographical boundaries and establish industrial carbon reduction synergy from the eastern to the central and western regions.