Extending the TPB Model in the Study of Gen Z’s Green Purchase Behavior: The roles of Obligations, Collective Efficacy, and Environmental Concern and Knowledge in Ho Chi Minh City

Abstract

The study examines factors influencing green purchase intention and behavior among Generation Z consumers in Ho Chi Minh City by extending the Theory of Planned Behavior (TPB). The research model integrates ethical obligation, moral obligation, environmental collective efficacy, environmental concern, environmental knowledge, social media usage, and attitude toward green products. Data were collected from 321 Gen Z consumers who had previously purchased green products and analyzed using PLS-SEM. The results indicate that moral obligation, ethical obligation, environmental collective efficacy, environmental concern, and attitude toward green products significantly influence green purchase intention. Environmental knowledge and social media usage do not have a direct effect on purchase intention; however, social media usage positively affects attitude, while environmental concern promotes the formation of environmental knowledge. Green purchase intention is confirmed as a strong predictor of actual green purchase behavior. The findings provide empirical evidence for the Vietnamese context and offer policy and managerial implications to promote sustainable green consumption among young consumers.