Combined excitation of microwave thermal field and electric field on doped ferroelectric catalyst of MgFe-LiNbO3 for lignin depolymerization

Lignin utilization is the main bottleneck restricting the full component utilization of lignocellulose, and hydrogenation depolymerization is an important method for efficient utilization of lignin. In response to the key challenges of low energy efficiency and low product selectivity in traditional depolymerization methods, as well as poor adaptability of microwave depolymerization catalysts, the paper proposed a strategy of microwave-excited the doped ferroelectric catalyst of MgFe-LiNbO 3 for lignin depolymerization. This work focused on the relationship between the doped catalyst and its activity and selectivity of catalyzing lignin depolymerization through experimental research and theoretical calculations. Surprisingly, it was revealed that the co-doped catalyst of MgFe-LiNbO 3 realized a complete conversion of 2-phenoxy-1-phenylethanol, with the phenol and styrene yield of 41.3 wt% and 12.15 wt%, respectively. The catalyst of MgFe-LiNbO 3 also exhibited a good universality in catalyzing lignin depolymerization and an excellent cycling stability. The DFT calculation further revealed that the internal cause of the improved catalytic activity lies in the improvement of the energy band structure and density of states distribution of LiNbO 3 after elements doping , as well as significant reduction of decisive step energy. This work has gained new insights of lignin efficient depolymerization.