Synergistic Evolution and Spatial-Temporal Differences in Green Technological Innovation and Carbon Emission Reduction in the Construction Industry from the Perspective of New Productive Forces

Green technological innovation, as a critical emerging resource element, is instrumental in advancing sustainable and high-quality development of the construction sector. However, despite extensive research, the synergistic mechanism linking regional green technology innovation (RGTI) and carbon reduction in the construction industry (CRCI) remains theoretically underexplored, especially through the lens of new quality productivity (NQP). Based on dynamic panel data from 30 Chinese provinces spanning 2013–2021, this study employed multiple analytical approaches, including econometric models, coupling coordination models, kernel density estimation, and Dagum Gini coefficient decomposition, to systematically examine their interactive relationships and spatiotemporal evolution characteristics. The findings reveal that RGTI directly reduces the carbon emissions intensity of the construction industry and yields a “dual-driving effect” through the mediating role of NQP. Significant coupling coordination effects were identified among RGTI, NQP, and CRCI. Further investigation showed that their synergistic evolution manifests distinct “regional lock-in effects” and “polarization effects”, with eastern regions achieving positive interactions, while central and western regions remain constrained by developmental limitations. Although overall disparities narrowed during the study period, inter-regional differences persisted as the dominant factor. This study extends the research perspective on construction industry carbon reduction, contributing to new quality productivity formation and inter-regional emission reduction coordination.