We review ionic liquid-based processes in the renewable energy field, including CO₂conversion, biomass conversion, solar energy and energy storage.

An environmentally benign catalytic system consisting of 1,8-diazabicyclo[5.4.0]-undec-7-ene (DBU) and cellulose was developed for CO₂ chemical fixation with epoxides under metal-free and halide-free conditions. Due to the dual roles played by DBU and cellulose on the activations of CO₂ and epoxide, the reaction could be performed with high activity and selectivity. A possible catalytic cycle for the hydrogen bond assisted ring-opening of epoxide and the activation of CO₂ induced by DBU was proposed. The process herein represents a simple, ecologically safe and efficient route for CO₂ chemical fixation into high value chemicals.