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Bifunctional ZnxMoy-TiO2were prepared through sol-gel methodology for efficient furfuryl alcohol (FAL) alcoholysis to ethyl levulinate (EL). From the comprehensive analysis, the abundant Brønsted and Lewis acidity distribution, enhanced reducibility ability, and the synergistic effect between Zn and Mo were found in Zn1Mo1–TiO2. Specially, Zn played an important role in enhancing acidity strength and reducibility from NH3-TPD and H2-TPR profiles, whereas Mo exhibited the highest FAL adsorption capacity. The simulative structure with the adjacent Zn–Mo and non-adjacent Zn–Mo with O vacancies in TiO2showed no difference in FAL adsorption energy and bader charge transfer capacity. After optimization, Zn1Mo1–TiO2exhibited the highest FAL conversion (98 %) and EL yield (80 %) with negligible 2-(ethoxymethyl)furan (EMF) and 5-ethoxy-5-(ethyl-oxidaneylidene) pentan-2-one (intermediate 4) yield under optimum condition (50 mg Zn1Mo1–TiO2, 170 °C, 7 h). Most importantly, the catalyst recyclability was performed in continuous flow until 700 min without obvious EL yield decrease. The rational design of the cost-effective bimetallic based TiO2will drive the green and efficient EL production in industrial scale.

Transition-metal phosphate/pyrophosphate always exhibits promising theoretical electrochemical performance and has essential prospects in supercapacitors. In this study, “rough bark-like” Co2P2O7is successfully synthesized via calcination method using ammonium cobalt phosphate as raw material. By investigating the effect of calcination temperature on the morphology of Co2P2O7, the pure cobalt pyrophosphate piece could be prepared at 600 °C (CPO-600). Due to the unique morphology and mesoporous presence, the CPO-600 exhibits a good affinity and infiltration interface with the electrolyte and displays a specific capacitance of 544 F g−1at 1 A g−1in 3 M KOH, which has excellent rate performance. After 10,000 cycles at 20 A g−1, it still maintains the good cycle stability with 81.48 % initial specific capacitance. Furthermore, the hybrid asymmetric aqueous supercapacitor of CPO-600//AC delivers remarkable energy densities of 10.6 Wh kg−1at power densities of 559 W kg−1. And its gel electrolyte device also provides higher electrochemical properties and good comprehensive performance.

Among the major challenges of the century, reducing the world's dependence on fossil fuels is the most important. In this context, several approaches have been considered, including the production of lignocellulosic ethanol or second-generation bioethanol. After this preprocessing, second-generation bioethanol is produced using a process involving four primary steps. Different processes of hydrolysis and fermentation are highlighted and then technology trends and barriers to industrial development are commented.