Green bond premium: A bibliometric analysis of emerging trends and future directions

This study provides a systematic mapping of the intellectual and conceptual landscape of the green bond premium, which is referred to as the ‘greenium’. Web of Science and Scopus were considered to analyze 532 documents from 204 sources, capturing the market’s evolution through recent post-pandemic and high-interest-rate environments, with an annual growth rate of 51.65% from 2012 to 2024. A co-word analysis and Walktrap clustering algorithm were applied for thematic network analysis. The study identifies four core thematic clusters that define the discourse: (1) Economic efficiency and financial markets (Niche theme); (2) Certification, quality, and information asymmetry (Motor theme); (3) Risk, performance, and investor behavior (Basic theme); and (4) Green economy and agricultural systems (Emerging theme). These clusters demonstrate a multidimensional research ecology where the ‘greenium’ is shaped by a complex interplay of market efficiency, regulatory signaling, and institutional trust. The findings suggest that the academic focus has transitioned from early conceptual inquiries to applied analysis of how certification standards and carbon risks influence yield spread. Researchers have reached consensus that supports the existence of a greenium, but its magnitude is shown to be context-dependent, fluctuating with market volatility, disclosure quality, and institutional frameworks. After clarifying these conceptual and methodological contours, the study offers an integrative framework for understanding sustainable finance. It also highlights critical areas for future research on the role of green bonds in sectoral climate transitions and the resilience of sustainable pricing in maturing markets.