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A robust and green strategy for the selective upgrading of biomass-derived platform chemicals towards highly valuable products is important for the sustainable development. Herein, the efficient electrocatalytic oxidation of biomass-derived furfuryl alcohol (FFA) into furoic acid (FurAc) catalyzed by the electrodeposited non-precious NiFe microflowers was successfully reached under the low temperature and ambient pressure. The 3D hierarchical NiFe microflowers assembled from ultrathin nanosheets were controllably synthesized by the electrodeposition method and uniformly grown on carbon fiber paper (CFP). Electrochemical analysis confirmed that NiFe nanosheets more preferred in the selective oxidation of FFA (FFAOR) than oxygen evolution reaction (OER). The linear sweep voltammetry (LSV) in FFAOR displayed a clear decrease towards lower potential, resulting in 30 mV reduction of overpotential at 20 mA cm−2 compared with that of OER. The optimal catalyst Ni1Fe2 nanosheets exhibited the highest selectivity of FurAc (94.0%) and 81.4% conversion of FFA within 3 h. Besides, the influence of various reaction parameters on FFAOR was then explored in details. After that, the reaction pathway was investigated and rationally proposed. The outstanding performance for FFAOR can be ascribed to the unique structure of 3D flower-like NiFe nanosheets and oxygen vacancies, resulting in large exposure of active sites, faster electron transfer and enhanced adsorption of reactants. Our findings highlight a facile and convenient mean with a promising green future, which is promising for processing of various biomass-derived platform chemicals into value-added products.

Rational synthesis of robust layered double hydroxides (LDHs) nanosheets for high-energy supercapacitors is full of challenges. Herein, we reported an ultrasonication-assisted strategy to eco-friendly fabricate NiFe-LDHs nanosheets for the enhanced capacitive behavior. The experimental results combined with different advanced characterization tools document that the utilization of ultrasonication has a profound effect on the morphology and thickness of the as-obtained NiFe-LDHs, alternatively affecting the capacitive behavior. It shows that NiFe-LDHs nanosheets prepared with 2-h ultrasonic treatments display the exceptional capacitive performance because of the synergetic effect of ultrathin thickness, large specific surface area, and high mesoporous volume. The maximum specific capacitance of Ni3Fe1-LDHs nanosheets with the thickness of 7.39 nm and the specific surface area of 77.16 m2 g−1 reached 1923 F g−1, which is competitive with most previously reported values. In addition, the maximum specific energy of the assembled NiFe-LDHs//AC asymmetric supercapacitor achieved 49.13 Wh kg−1 at 400 W kg−1. This work provides a green technology to fabricate LDHs nanosheets, and offers deep insights for understanding the relationship between the morphology/structure and capacitive behavior of LDHs nanosheets, which is helpful for achieving high-performance LDHs-based electrode materials.