A theoretical study of the effect and mechanism of FeN_(3)-doped biochar for greenhouse gas mitigation

Paddy fields are a major emission source of greenhouse gases(GHGs)[for instance,methane(CH4),nitrous oxide(N_(2)O),and carbon dioxide(CO_(2))]among agricultural fields.Biochar has been deemed a potential candidate for the reduction of GHGs in paddy fields.However,there is no consistent conclusion that biochar can simultaneously reduce emissions of CH4,N_(2)O,and CO_(2).Herein,we proposed the FeN_(3)-doped biochar(FG)as an excellent material for GHGs restriction in paddy fields via the first-principles calculation.The computation results indicated that the FG exhibited satisfactory adsorption ability for CH4,CO_(2),and N_(2)O,which improved the adsorption energies to−1.37,−1.54,and−2.91 eV,respectively.Moreover,the density of state(DOS)analyses revealed that the factor responsible for FeN_(3)-doped biochar to exhibit excellent adsorption ability was the occurrence of drastic energy up-or down-shift of the electron for Fe d,C p,O p,or N p orbital upon adsorption of CH4,CO_(2),or N_(2)O.Our study suggested an advanced modified biochar material for reducing the GHGs emissions in paddy fields,in addition to exploring the adsorption properties and mechanisms of FeN_(3)-doped biochar for GHGs mitigation,which provided a strategy to explore biochar modification and efficient emission reduction materials.