Fabrication and supercapadtive properties of Fe_2O_3@C nanocomposites

摘要

Fe_2O_3@C nanocomposites (denoted as FeC-n, n represents the weight percent of Fe(NO_3)_3-9H_2O in the starting gel) have been fabricated by pyrolyzing Fe(NO_3)3-9H_2O impregnated starch gels. When the Fe(NO_3)_3-9H_2O content was below 50 wt.%, the products contained well dispersive and uniform γ-Fe_2O_3 nanoparticles that embedded in the carbon matrix. The particle sizes were positively related to the content of Fe(NO_3)3-9H_2O. The nanocomposites FeC-50 that contained 4.25 nm nanoparticles exhibited an enhanced electrochemical performance within the voltage window of -1.3-0.4 V in 6mol L~(-1) KOH solutions. The symmetric capacitor of FeC-50 possessed a high specific capacitance (SC) of 267.2 Fg~(-1) at 035 Ag~(-1) with a high voltage of 1.4 V.