Does the dual-pilot policy of low-carbon city and sci-tech finance improve urban green total factor productivity?

This study investigates whether a dual-pilot (DP) policy—merging the low-carbon city pilot and sci-tech finance pilot—enhances urban green total factor productivity (GTFP) in China. It aims to clarify both the effects and the underlying mechanisms, as well as to assess the heterogeneity of outcomes across cities. Panel data from 281 Chinese cities spanning 2004 to 2021 are analyzed using a multi-period difference-in-differences framework. Urban GTFP is measured by Global Malmquist-Luenberger (GML) index method of Slacks-Based Measure (SBM) model, while three key pathways—green technology innovation, environmental protection investment, and government environmental concern—are examined to understand the mechanisms behind policy effects. Findings indicate that the DP policy generates a distinct synergistic effect that strengthens urban GTFP and contributes to its growth by spurring green technology innovation, expanding environmental protection investment, and increasing government environmental concern. Cities implementing both low-carbon and sci-tech finance measures exhibit significantly greater improvements in GTFP than those adopting only a single-pilot policy. Furthermore, the magnitude of policy impact varies according to the level of government support and sci-tech expenditure. The results highlight that the scope of the dual-policy pilot should be expanded, policy synergy should be strengthened, and the integrated development should be promoted. With “incremental quality improvement” as the guiding aim, attention should center on how these policies foster green technology innovation, raise environmental protection investment levels, and reinforce government environmental concern. Furthermore, the government and market should play a coordinated role in implementing the DP policy attuned to local conditions and needs.