Oxocarbons(C_(n)O_(n),n=3,4,5,6,...)are a series of compounds that are only composed of carbonyl groups.The highly electrophilic carbon atoms in C_(n)O_(n)make their poor stability toward H_(2)O,and thus the synthesis...Oxocarbons(C_(n)O_(n),n=3,4,5,6,...)are a series of compounds that are only composed of carbonyl groups.The highly electrophilic carbon atoms in C_(n)O_(n)make their poor stability toward H_(2)O,and thus the synthesis of C_(n)O_(n)is very challenging.Here an oxidation-dehydration method is developed to successfully synthesize C_(4)O_(4)and C_(5)O_(5).The combination of nuclear magnetic resonance(^(13)C NMR,^(1)H NMR),mass spectra,and infrared spectra unambiguously proves the exact chemical structure of C_(4)O_(4)and C_(5)O_(5).When used as a cathode material in lithium-ion batteries(LIBs),C_(5)O_(5)could deliver a high discharge capacity of 698m Ah g-1(corresponding to an energy density of 1,256 Wh kg-1C_(5)O_(5)).Furthermore,ex-situ infrared spectra and density functional theory(DFT)calculations demonstrate that the carbonyl groups are redox active sites during discharge and charge processes.This work paves the way to achieve the synthesis and battery application of oxocarbons.展开更多
基金supported by the National Key R&D Program of China(2022YFB2402200)the National Natural Science Foundation of China(21905143,22121005,22020102002,21835004)Frontiers Science Center for New Organic Matter of Nankai University(63181206)。
文摘Oxocarbons(C_(n)O_(n),n=3,4,5,6,...)are a series of compounds that are only composed of carbonyl groups.The highly electrophilic carbon atoms in C_(n)O_(n)make their poor stability toward H_(2)O,and thus the synthesis of C_(n)O_(n)is very challenging.Here an oxidation-dehydration method is developed to successfully synthesize C_(4)O_(4)and C_(5)O_(5).The combination of nuclear magnetic resonance(^(13)C NMR,^(1)H NMR),mass spectra,and infrared spectra unambiguously proves the exact chemical structure of C_(4)O_(4)and C_(5)O_(5).When used as a cathode material in lithium-ion batteries(LIBs),C_(5)O_(5)could deliver a high discharge capacity of 698m Ah g-1(corresponding to an energy density of 1,256 Wh kg-1C_(5)O_(5)).Furthermore,ex-situ infrared spectra and density functional theory(DFT)calculations demonstrate that the carbonyl groups are redox active sites during discharge and charge processes.This work paves the way to achieve the synthesis and battery application of oxocarbons.
