Towards technology-convergent cities: How does the low-carbon economy contribute?

This paper tests whether dual-purpose policy promotes digital–green technology convergence (DGTC) by expanding domain-specific technological stocks within a policy impetus–technological accumulation–technological convergence framework. We evaluate this mechanism in the context of China’s Low-Carbon City Pilot (LCCP). Using a city–year panel of 264 Chinese prefecture-level cities from 2008–2023, DGTC is measured with two classic patent-based indicators—co-classification and cross-domain direct citation. The mediating mechanism is captured as digital and green technology accumulation through patent stocks and counts of innovating entities in both domains. Heterogeneity is examined with respect to policy implementation conditions, focusing on city endowments and the digital–green ecosystem. The empirical results show that the LCCP significantly increases DGTC, with consistent effects across both indicators and robust to multiple checks. Mediation analyses indicate that the LCCP raises digital and green accumulation, with stronger effects on the digital side and similar but milder effects on the green side. Heterogeneity tests reveal stronger effects in eastern and mega/large cities, as well as in contexts where intellectual property protection is tighter, network infrastructure more advanced, and government or public attention to green goals higher. Taken together, the study reaffirms that policy is an important driver of technological convergence. Using a nationwide, long-span city-level dataset, it constructs and validates two co-primary city-level DGTC measures with novel scope and comprehensive urban coverage, providing actionable evidence for designing and implementing context-specific policy portfolios.