Carbon lever and green gear: how firm-level carbon finance sparks green innovation efficiency in manufacturing

In the face of mounting pressure on global initiatives to combat climate change, the question of how to capitalize on the opportunity presented by green transformation has become a pressing concern. Unlike the concept of green finance, carbon finance (CF) is a specific means dedicated to reducing greenhouse gases. Its essence lies in emerging financial tools based on strict technical accounting, with carbon emissions as the primary commodity and reliance on the financial market. Therefore, based on the data of A-share listed manufacturing enterprises from 2009 to 2023, this study constructs a carbon finance measurement at the firm level and explores the causal relationship between CF and the green innovation efficiency (GIE) of manufacturing enterprises. The findings indicate that: (1) Enterprises’ CF can boost the GIE. High-tech manufacturing companies, as well as those in the mature and declining stages, exhibit this boosting influence in particular. (2) The development of CF can enhance the GIE of enterprises through two main channels: increasing the proportion of senior executives with environmental backgrounds and improving the short-term debt-paying ability of enterprises. (3) The impact of CF is moderated both positively and negatively by the degree of digital integration (Dig) and financing constraints (Sa). The level of Dig and Sa play a positive and negative moderation role in the impact of carbon finance. The results provide a reference for the application of carbon financial tools in the entity economy from a micro perspective.