How do complementary technological linkages affect carbon emissions efficiency?

Complementary technological linkages provide access to the external technology at lower cost and compensate for weak or absent local technological capabilities, which has an important role in improving carbon emissions efficiency. This study examines this issue in the industrial sector in China. First, input-output data are reconstructed, and the industrial carbon emissions efficiency of each province in China is calculated using the super-SBM DEA method. Second, we examine patent text data to measure complementary technological linkages, applying the principle of co-occurrence. We also calculate regional technological capabilities, which are further divided into related and unrelated technological diversification. Third, we apply a benchmark model combined with moderating effect tests. The results reveal an inverted U-shaped impact of complementary technological linkages on industrial carbon emissions efficiency, while the impact of the number of interregional linkages is U-shaped. The interactive term of regional technological capabilities and complementary technological linkages have a positive effect on industrial carbon emissions efficiency, while the interactive effect of related technological diversification and complementary technological linkages on industrial carbon emissions efficiency is positive and larger than that of unrelated technological diversification. The moderating effect tests indicate that in comparison to low-income regions, the interactive term of regional technological capabilities and complementary technological linkages in high-income regions has a negative influence on industrial carbon emissions efficiency. Furthermore, unrelated technological diversification matches better with complementary technological linkages in promoting industrial carbon emissions efficiency in high-income regions than related technological diversification. The results of this study can help regional policymakers to choose different innovative strategies to achieve the green transition.