Research on the adsorption of environmentally friendly insulating gas C_(4)F_(7)N decomposed components on the surface ofγ-Al_(2)O_(3)

C_(4)F_(7)N is considered to be the most potential alternative gas for SF_(6).However,harmful decomposition by-products generated by the discharge or overheating faults will pose threat to safe operation and service life of gas insulated equipment(GIE).Herein,we investigated the adsorption performance ofγ-Al_(2)O_(3)on C_(4)F_(7)N and its decomposition products to evaluate the possibility of using it as by-products adsorbent or exhaust treatment material.It is found thatγ-Al_(2)O_(3)demonstrates superior adsorption capacity for CF_(4),C_(2)F_(6),C_(3)F_(8),C_(3)F_(6),C_(2)F_(4),and keeps stable after the interaction.The first-principles calculation infers thatγ-Al_(2)O_(3)has stronger interaction with C_(4)F_(7)N,C_(3)F_(6)and C_(3)F_(8)than that of C_(2)F_(4),C_(2)F_(6)and CF_(4).There exists obvious charge transfer between C_(4)F_(7)N andγ-Al_(2)O_(3),which belongs to chemisorption.The interaction between F 2p orbital and C=Cπorbital determines the gas-solid adsorption performance.The desorption properties were also explored and the recovery time was in order of CF_(4)<C_(2)F_(6)<C_(2)F_(4)<C_(3)F_(8)<C_(4)F_(7)N<C_(3)F_(6).Overall,theγ-Al_(2)O_(3)is inappropriate to be used as the adsorbent for decomposition by-products of C_(4)F_(7)N gas mixture-based GIE,while it can be used as exhaust treatment material for C_(4)F_(7)N wasted gas.