In this paper， a high value-added utilization method of rice husk char was proposed to prepare lanthanum-supported porous carbon composite electrode materials（La/PCs）. A series of La/PCs were prepared via in situ activation/loading method. The effects of calcination temperature and impregnation ratio on the adsorption and electrochemical properties of La/PCs were investigated. X-Ray diffraction（XRD）， X-ray photoelectron spectroscopy（XPS）， scanning electron microscope-energy dispersive spectrometer（SEM-EDS） and Brunauer-Emmett-Teller surface area（BET） were used to study the metal structure， valence state， element compositions and surface morphology of those La/PCs. It was analyzed that the possible relationship between pore structure and capacitance value. As a result， the La/PC_900/10 exhibited high gravimetric capacitance of 269.45 F/g in 6 mol/L KOH electrolyte. At 0.5 A/g， the assembled symmetric supercapacitor presented a superior gravimetric energy density of 23.45 W·h/kg at 0.70 kW/kg and the capacitance retention rate was 86.41% after 5000 cycles. The favorable capacitive behavior of La/PC_900/10 demonstrated its potential as carbon-based electrode applied in high performance supercapacitors. This paper provides a feasible path for the utilization of rice husk char and the application of lanthanum in the field of new energy materials.
