Are emerging BRICST economies greening? An empirical analysis from green innovation efficiency perspective

Green innovation solves the dilemma of economic growth, energy conservation, and ecological protection to achieve innovation-driven sustainable development. On this premise, it is reasonable to assess the performance of technology innovation for promoting green development. In this context, this study examines green innovation efficiency (GIE) and its influencing mechanisms in rapidly emerging BRICST economies (i.e., Brazil, Russia, India, China, South Africa, and Turkey) during 2000–2021 by adopting the novel super ray slack-based measure model with undesirable output and the dynamic panel data model. As a novelty, we have evaluated GIE by constructing a comprehensive input–output index system based on innovation, energy, economic, and environmental factors. The empirical result reveals an increasing wave-shaped trend of GIE fluctuating around 0.606, failing to be DEA-efficient where inefficient countries need to improve by at least 39.40% to become efficient. There is an emerging gap with individual differences among countries, which is highest in Brazil and lowest in India. Moreover, green technology development and environmental regulation are highly conductive to improve GIE. However, foreign direct investment and government support have a mere positive effect, while trade openness has an inhibitory impact on GIE. These results suggest that individual governments should support technical cooperative relationships to formulate stringent but distinct green innovation policies based on domestic conditions, improve innovation-driven technological development and environmental regulation, encourage adoption and utilization of energy-efficient and clean technologies, enhance sustainable foreign investment and governmental research and development funds, synchronize trade baskets to improve trade diversification, and strengthen absorptive capacity of domestic enterprises. Graphical Abstract: (Figure presented.)