Page 387 - ISC PROCEEDINGS 21.4

H1: Price perception positively influences sustainable product purchasing behavior.
2.2.2. Green knowledge (GK)
Environmental knowledge and awareness of sustainability certifications play a
foundational role in shaping green purchasing behavior. Akandere and Gümrah (2025)
demonstrated that environmental knowledge significantly and positively affects green
purchasing behavior among university students. In the digital economy, access to
information about sustainable products has been democratized through online platforms,
potentially amplifying the role of knowledge.
H2: Green knowledge positively influences sustainable product purchasing behavior.
2.2.3. Perceived quality and trust (PQ)
Consumer trust in the quality and authenticity of sustainable products is a critical
determinant of purchase decisions (Schiaroli, Dangelico, & Fraccascia, 2025). In contexts
where greenwashing is prevalent, perceived quality serves as a risk-reduction mechanism.
H3: Perceived quality positively influences sustainable product-purchasing behavior.
2.2.4. Social influence (SI)
Social norms and peer influence are central constructs in TPB. In the digital
economy, social influence extends beyond face-to-face interactions to encompass online
peer reviews, social media communities, and digital word-of-mouth (Wu, Lim, & Lim,
2025).
H4: Social influence positively affects sustainable product purchasing behavior.
2.2.5. Green marketing (GM)
Digital green marketing, including targeted advertising, content marketing, and
promotional campaigns on social media platforms, represents a primary channel through
which enterprises communicate sustainability credentials to Gen Z consumers. Su and Li
(2024) demonstrates that green advertising and environmental knowledge are dual
drivers of green purchase intention, with their effects amplified by eco-labels and brand
innovation.
H5: Green marketing positively influences sustainable product purchasing behavior.
2.3. Moderating variables: digital-age phenomena
2.3.1. Influencer endorsement (INFLU)
Social media influencers have emerged as powerful intermediaries in the green
consumption ecosystem. Zhao et al. (2024) show that consumers prefer “informer-type”
influencers for green products, with trust as the key mediating mechanism. Wu et al.
(2025) further demonstrate that green influencer marketing positively affects consumer
trust in green products. We hypothesize that influencer endorsement amplifies the effect
of perceived quality on purchasing behavior because influencer credibility reinforces
consumers' trust in product quality claims.
H6: Influencer endorsement positively moderates the relationship between
perceived quality and sustainable purchasing behavior.
2.3.2. Fear of missing out – FOMO
FOMO is a digital-age psychological phenomenon driven by social media exposure,
limited-time offers, and social comparison. A recent study of 492 Gen Z consumers in Ho
Chi Minh City found that FOMO positively affects green consumption intention through
mediating roles of attitude, motivation, and subjective norms (Nghiem & Tien, 2025). We
hypothesize that FOMO amplifies the impact of green marketing, as time-limited
promotions and trending sustainable products create urgency.

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