In the context of carbon neutrality, environmental innovation has become an important way for companies to achieve sustainable development and gain a competitive advantage. To systematically grasp the current status of the environmental innovation literature, this study conducted a thematic modeling and coding analysis of 19,936 papers published between 2000 and 2022 using an unsupervised thematic model. The research content pertaining to environmental innovation was sorted following the logic of "influencing factors, boundary conditions, and influencing outcomes." The results showed that previous scholars had classified the factors driving environmental innovation based primarily on five theories, including stakeholder theory, resource-based theory, institutional theory, informal institutional theory and upper echelons theory. Green absorptive capacity, firm size, and slack resources played a moderating role in the influence of other factors on environmental innovation, but the relationship between environmental innovation and firm performance remained uncertain. Finally, combining the limitations of previous studies, we outline several directions for future research to achieve breakthroughs.