Surface-redox pseudocapacitive nanomaterials show promise for fast-charging energy storage.However,their high surface area usually leads to low density,which is not conducive to achieving both high volumetric capacity...Surface-redox pseudocapacitive nanomaterials show promise for fast-charging energy storage.However,their high surface area usually leads to low density,which is not conducive to achieving both high volumetric capacity and high-rate capability.Herein,we demonstrate that TiO_(2)nanosheets(meso-TiO_(2)-NSs)with densely packed mesoporous are capable of fast pseudocapacitance-dominated sodium-ion storage,as well as high volumetric and gravimetric capacities.Through compressing treatment,the compaction density of meso-TiO_(2)-NSs is up to~1.6g/cm^(2),combined with high surface area and high porosity with mesopore channels for rapid Na+diffusion.The compacted meso-TiO_(2)-NSs electrodes achieve high pseudocapacitance(93.6%of total charge at 1mV/s),high-rate capability(up to 10 A/g),and long-term cycling stability(10,000 cycles).More importantly,the space-efficiently packed structure enables high volumetric capacity.The thick-film meso-TiO_(2)-NSs anode with the mass loading of 10mg/cm^(2)delivers a gravimetric capacity of 165 mAh/g and a volumetric capacity of 223 mAh/cm^(3)at 5 mA/cm^(2),much higher than those of commercial hard carbon anode(80mAh/g and 86mAh/cm^(3)).This work highlights a pathway for designing a dense nanostructure that enables fast charge kinetics for high-density sodium-ion storage.展开更多
基金support from the National Natural Science Foundation of China(Nos.22005256,22179-113),the Natural Science Foundation of Fujian Province of China(No.2020J01034)Fundamental Research Funds for the Central Universities(Nos.20720210045,2072-0210084)+4 种基金Science and Technology Projects of Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM)(No.HRTP-2022-19)Kun Lan acknowledges the support from the National Natural Science Foundation of China(No.22205118)the“Junma"Program of Inner Mongolia University(No.21300-5223715)the Grassland Talent Program of Inner Mongolia Autonomous Region of China.Haobin Wu acknowledges the support the Zhejiang Provincial Natural Science Foundation(No.LR21E020003)the National Natural Science Foundation of China(No.22005266).
文摘Surface-redox pseudocapacitive nanomaterials show promise for fast-charging energy storage.However,their high surface area usually leads to low density,which is not conducive to achieving both high volumetric capacity and high-rate capability.Herein,we demonstrate that TiO_(2)nanosheets(meso-TiO_(2)-NSs)with densely packed mesoporous are capable of fast pseudocapacitance-dominated sodium-ion storage,as well as high volumetric and gravimetric capacities.Through compressing treatment,the compaction density of meso-TiO_(2)-NSs is up to~1.6g/cm^(2),combined with high surface area and high porosity with mesopore channels for rapid Na+diffusion.The compacted meso-TiO_(2)-NSs electrodes achieve high pseudocapacitance(93.6%of total charge at 1mV/s),high-rate capability(up to 10 A/g),and long-term cycling stability(10,000 cycles).More importantly,the space-efficiently packed structure enables high volumetric capacity.The thick-film meso-TiO_(2)-NSs anode with the mass loading of 10mg/cm^(2)delivers a gravimetric capacity of 165 mAh/g and a volumetric capacity of 223 mAh/cm^(3)at 5 mA/cm^(2),much higher than those of commercial hard carbon anode(80mAh/g and 86mAh/cm^(3)).This work highlights a pathway for designing a dense nanostructure that enables fast charge kinetics for high-density sodium-ion storage.
