Abstract: In-depth research on the impact and mechanism of financial technology development on urban carbon emissions has important theoretical and practical significance for accurately formulating emission reduction policies, developing low-carbon economies, and promoting smart carbon reduction in cities. Unlike previous studies that focused on a single dimension within a region, this paper calculates the financial technology development index of Chinese cities and examines the impact and mechanism of financial technology development on urban carbon emissions from both within and between regions based on panel data of 264 Chinese cities from 2011 to 2019. The results show that financial technology development within a region can significantly reduce urban carbon dioxide emissions, and this conclusion still holds after using instrumental variables to mitigate endogeneity and replacing financial technology development indicators in a series of robustness tests. Mechanism analysis indicates that financial technology can reduce urban carbon emissions by improving technological innovation and resource allocation efficiency. There is a significant spatial correlation between financial technology development and carbon dioxide emissions between regions. And although financial technology can reduce local urban carbon emissions, it can also promote carbon dioxide emissions in neighboring cities, showing a "beggar-thy-neighbor" phenomenon. Further research on the different performance of financial technology carbon reduction effects within and between regions shows that the carbon reduction effect of financial technology is significantly stronger in northern cities than in southern cities, significantly stronger in non-urban agglomeration cities than in urban agglomeration cities, and significantly stronger in other cities than in central cities.

Key words: fintech, urban carbon emissions, technological innovation, resource allocation