统计研究

低碳城市建设是实现“双碳”目标和经济绿色转型的重要举措。客观评估低碳城市建设对企业绿色技术创新的影响，是当下亟需探讨的重要议题。本文选取2006—2023年我国A股上市公司样本，结合双重机器学习的因果推断方法，探究低碳城市建设对企业绿色技术创新的影响，考察其在不同所有制属性、污染程度与技术水平企业中的异质性，并进一步分析数字经济与制度环境的调节作用。研究发现，从创新产出层面来看，低碳城市建设不仅显著提升企业绿色技术创新数量，也有效促进绿色技术创新质量的提高；从创新方向层面来看，低碳城市建设主要推动末端治理型绿色技术创新。异质性分析表明，低碳城市建设对企业绿色技术创新的促进作用在国有企业、重污染企业和高新技术企业中更加显著。机制检验发现，低碳城市建设通过提升绿色金融发展水平与居民绿色消费水平，推动企业绿色技术创新。调节作用结果显示，数字经济发展和良好的制度环境能够进一步增强低碳城市建设对企业绿色技术创新的促进效应。本文研究不仅拓宽低碳城市建设成效评估的视野，还有助于促进政府、金融机构、公众和企业形成低碳转型的合力，为我国实现“双碳”目标与经济高质量发展提供有益启示。

The construction of low-carbon cities is an important initiative for achieving carbon peaking and neutrality goals and promoting economic green transformation. Objectively assessing the impact of low-carbon city construction on corporate green technology innovation is an important topic that needs to be discussed. Drawing on a panel of Chinese A-share listed firms from 2006 to 2023 and leveraging a double machine learning causal inference framework, this paper assesses the impact of low-carbon city construction on corporate green technology innovation, investigates heterogeneity across ownership structures, pollution intensity, and technological capability. Additionally, it further analyzes the moderating roles of the digital economy and institutional environment in the relationship between the two. The results demonstrate that low-carbon city construction significantly enhances both the quantity and quality of corporate green technology innovation, and in terms of innovation orientation it primarily drives technologies focused on end-of-pipe emission abatement. Heterogeneity analysis indicates that the promotion of green technology innovation by low-carbon city construction is more pronounced among state-owned enterprises, heavily polluting enterprises, and high-tech enterprises. Mechanism tests show that low-carbon city construction primarily stimulates corporate green technology innovation by elevating the level of green finance development and encouraging green consumption among residents. Furthermore, the moderating effect results indicate that both digital economy development and a supportive institutional environment bolster the positive impact of low-carbon city construction on corporate green technology innovation. This paper broadens the assessment of the effectiveness of low-carbon city construction, helps promote the low-carbon transformation synergy among the government, financial institutions, the public and enterprises, and provides beneficial inspiration for China to achieve the goal of carbon peaking and neutrality and high-quality economic development.