Aqueous zinc-ion batteries(AZIBs)have significant promise as large-scale energy storage devices due to their high safety,low cost,and environmental friendliness.However,their application has been constrained by limite...Aqueous zinc-ion batteries(AZIBs)have significant promise as large-scale energy storage devices due to their high safety,low cost,and environmental friendliness.However,their application has been constrained by limited operational voltage windows.A high-voltage-resistant Ti-graphene-Ti cathode current collector(TGT)was designed and fabricated by three-dimensional(3D)printing.The surface of the TGT has a TixOy protective layer,which effectively suppresses electrolyte decomposition under high voltage conditions so that the voltage window of the battery is extended to 1.0-2.2 V without the obvious formation of by-products.Simultaneously,the graphene layer in the TGT structure significantly improves the adsorption and insertion/extraction kinetics of cations,resulting in a high specific capacity of 307.5 mAh g−1and a prolonged cycling life of the battery.The resultant AZIBs have a stable charge/discharge performance over 400 cycles at a high voltage.Furthermore,the influence of the geometric arrangements of Ti and graphene in the 3D printing process on the energy storage mechanism was investigated and provided novel insight for the development of high-voltage-resistant composite cathode current collectors for AZIBs.展开更多
Pitch is an excellent precursor for the production of hard carbon,with pre-oxidation crucial process in the fabrication.The structural changes in the different molecular components of pitch during thermochemical treat...Pitch is an excellent precursor for the production of hard carbon,with pre-oxidation crucial process in the fabrication.The structural changes in the different molecular components of pitch during thermochemical treatment are a key factor in determining the sodium-ion storage of pitchbased hard carbon anodes.We investigated the effects of the different molecular structures in the asphaltene precursor,including aromatic rings and aliphatic chains,on the sodiumion storage behavior of the resulting carbon.We found that polar oxygen functional groups limit the steric hindrance caused by the aromatic rings in pitch,and thus facilitate the introduction of cross-linked structures.During high-temperature carbonization,aromatic rings form a rigid carbon framework that prevents the rearrangement of ordered carbon layers,leading to a short-range disordered carbon structure and promotes the production of closed pores.For example,a material prepared from asphaltene,which contains a large number of oxygen-containing functional groups and macromolecular aromatic rings,using pre-oxidation at 300℃ and carbonization at 1200℃ had a reversible capacity of 316.7 mAh g−1 when used as the anode for sodium ion batteries.Our research provides a theoretical basis for the selection of raw materials for the development of high-quality pitch-based hard carbons.展开更多
基金financial support from National Natural Science Foundation of China(22179145)Shandong Provincial Natural Science Foundation(ZR2023LFG005)+1 种基金Qingdao Natural Science Foundation(24-8-4-zrjj-5-jch)Science and Technology Park Incubation Program Project of Qingdao City(25-1-1-yqpy-33-qy).
摘要Aqueous zinc-ion batteries(AZIBs)have significant promise as large-scale energy storage devices due to their high safety,low cost,and environmental friendliness.However,their application has been constrained by limited operational voltage windows.A high-voltage-resistant Ti-graphene-Ti cathode current collector(TGT)was designed and fabricated by three-dimensional(3D)printing.The surface of the TGT has a TixOy protective layer,which effectively suppresses electrolyte decomposition under high voltage conditions so that the voltage window of the battery is extended to 1.0-2.2 V without the obvious formation of by-products.Simultaneously,the graphene layer in the TGT structure significantly improves the adsorption and insertion/extraction kinetics of cations,resulting in a high specific capacity of 307.5 mAh g−1and a prolonged cycling life of the battery.The resultant AZIBs have a stable charge/discharge performance over 400 cycles at a high voltage.Furthermore,the influence of the geometric arrangements of Ti and graphene in the 3D printing process on the energy storage mechanism was investigated and provided novel insight for the development of high-voltage-resistant composite cathode current collectors for AZIBs.
摘要Pitch is an excellent precursor for the production of hard carbon,with pre-oxidation crucial process in the fabrication.The structural changes in the different molecular components of pitch during thermochemical treatment are a key factor in determining the sodium-ion storage of pitchbased hard carbon anodes.We investigated the effects of the different molecular structures in the asphaltene precursor,including aromatic rings and aliphatic chains,on the sodiumion storage behavior of the resulting carbon.We found that polar oxygen functional groups limit the steric hindrance caused by the aromatic rings in pitch,and thus facilitate the introduction of cross-linked structures.During high-temperature carbonization,aromatic rings form a rigid carbon framework that prevents the rearrangement of ordered carbon layers,leading to a short-range disordered carbon structure and promotes the production of closed pores.For example,a material prepared from asphaltene,which contains a large number of oxygen-containing functional groups and macromolecular aromatic rings,using pre-oxidation at 300℃ and carbonization at 1200℃ had a reversible capacity of 316.7 mAh g−1 when used as the anode for sodium ion batteries.Our research provides a theoretical basis for the selection of raw materials for the development of high-quality pitch-based hard carbons.