Synthesis And Performance Research Of Biomass Derived Carbon Material As Orr Electrocatalyst

The electrocatalyst in energy conversion processes have vital importance on the conversion efficiency and the spread of its related application.Taking oxygen reduction reaction as example,the high cost,low stability and poison effect of state of art Pt/C material restricts the wider development of fuel cell.Thus,developing newly stable,efficient and low-cost electrocatalyst has been the keen spot in energy conversion field.A successful electrocatalyst should possess effective active sites,meanwhile,efficient mass and electro transport.Biomass naturally contains multiple metal and heteroatoms,making them suitable candidates of precursor of carbon electrocatalyst.Herein,we selected two representative biomass(nanofibrillated cellulose and fungi residue)as main precursors,successfully design,synthesis and optimize two biomass derived carbon materials according to their composition and structure advantages.We make a systematic investigation of their electrocatalytic performance(ORR?OER),meanwhile,analysis the origin of their performance by different characterization method.The nanofibrillated cellulose and fungi residue derived carbon material show promising electrocatalytic performance.Specifically,1)the onset potential of NCPY Fe-N-C electrocatalyst which derived from nanofibrillated cellulose,pyrrole and FeC13 reaches 0.84 V,the current density reaches 4 mA cm-2.The onset potential exceed the state of art carbon black of 2e-ORR and approach the state of art 20%Pt/C of 4e-ORR.Meanwhile,NCPY also show part of OER catalytic performance,denotes the application potential of bi-functional electrocatalyst.2)As the in-situ synthesized multi non-precious metal doped electrocatalyst from fungi residue(FRC),FRC shows top performance among H2O2 electrocatalysis(2e-ORR),the maximum of H2O2 selectivity reaches 98%and remain above 91%in wide potential range(-0.7 V?-0.3 V),the ring current density reaches 0.45 mA cm-2(-0.5 V).The selectivity of FRC exceeds almost all metal contained carbon materials in alkaline medium to our knowledge,making it highly promising low cost electrocatalyst for H2O2 electrogeneration.The origin of high catalytic performance of two materials mainly come from the heteroatom and metal that naturally existed in biomass precursors.Besides,the 3D structure of biomaterials and oxygen functional groups on their surface also contribute to the high performance.The studies of pure biomass and waste biomass provide promising and low cost electrocatalysts for real application,exploring a new direction for ORR electrocatalyst development,meanwhile,providing reference for the synthesis and characterization of biomass derived carbon materials in the future.