LAUSR

Carbon efficiency has attracted increased attention due to the carbon neutrality goal of various responsible countries, including China. R&D element has been proved to be an effective method to promote carbon efficiency from a static perspective without considering spatial factors. However, due to regional inequality in China, the level of carbon efficiency and R&D element flow vary in different regions. If ignoring the importance of R&D element flow from a dynamic perspective and neglecting the spatial factors of carbon efficiency convergence, it may be not conducive to the improvement of carbon efficiency and its overall development. Thus, this study proposes a gravity model to figure out the specific condition of R&D element flow (including R&D personnel flow and R&D capital flow) between Chinese provinces and cities from 2009 to 2019, builds up a MinDS model with undesirable outputs to estimate carbon efficiency and analyzes the characteristics of regional carbon efficiency with kernel density estimation, and employs a spatial Durbin model to investigate the effect of R&D element flow on regional carbon efficiency convergence. The results show that, firstly, the R&D personnel flow and R&D capital flow show a gathering trend in the neighboring regions, and the flow distribution is unbalanced. Secondly, the overall regional carbon efficiency has improved at first, then decreased gradually. There are large spatial differences among Chinese regional carbon efficiency, and the carbon efficiency between provinces and cities converges. Thirdly, R&D element flow promotes regional carbon efficiency convergence. The results of this study can be useful for solving the problem of unequal regional carbon efficiency development by managing the distribution and transfer of R&D element among provinces and cities.