The effectiveness of promoting green products in an effort to reduce carbon emissions relies heavily on understanding the mechanisms that influence green purchasing behavior. These mechanisms, however, remain both controversial and unclear, necessitating a thorough investigation to identify and decipher their underlying impacts. This paper presents a comprehensive dual-study analysis employing a mixed-methods approach to demystify this subject. Our first study tests the “net effect” mechanism of a theoretical model based on responses from 611 questionnaires from Chinese customers. Utilizing hierarchical regression analysis and Bootstrap confidence intervals, we examine the main effect, mediating effect, moderating effect, and moderated mediating effect to construct a more distinct “net effect” model than previously available. In the second study, the fuzzy set qualitative comparative analysis method (fs-QCA) is employed to examine the different antecedent variables affecting green purchasing behavior. The findings show no single determinant is essential; instead, green purchasing behavior follows three distinct patterns - namely, internal autogenous, environment-oriented, and individual profit-driven. Further analysis reveals that each pattern hinges on “green trust” to facilitate green purchasing behavior. The findings offer significant contributions to the understanding of the role environmental values play in green purchasing behavior. Moreover, it furnishes empirical insights that fostering consumers toward low-carbon consumption.