Aluminum nitride （AlN） films with h〈100〉 crystalline orientation are fabricated on p-Si （100） substrates at room tempera- ture by pulsed laser deposition. The effects of laser energy density and annealing on the...Aluminum nitride （AlN） films with h〈100〉 crystalline orientation are fabricated on p-Si （100） substrates at room tempera- ture by pulsed laser deposition. The effects of laser energy density and annealing on the quality of the films are studied by x-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. The crystalline quality of AlN films is improved considerably by increasing the laser energy density while there is increased number of farraginous particles on the surface. The annealing treatment at 600~C produces a recrystallization process in the film, characterized by the improvement of the original crystallinity, the appearance of new crystalline orientations, and the increase of the crystallites. The surface becomes rougher due to the increase of the grain size during annealing.展开更多
Hydrogel systems promote the development of flexible energy storage devices because of their inherent mechanical elasticity and ionic conductivity.However,achieving stable energy storage capacity under violent mechani...Hydrogel systems promote the development of flexible energy storage devices because of their inherent mechanical elasticity and ionic conductivity.However,achieving stable energy storage capacity under violent mechanical deformation is still a challenge for hydrogel devices.In this work,an all-in-one integrated supercapacitor(AISC)was assembled using in situ deposited polyaniline/graphene oxide nanocomposites for both sides of the incorporated ionic hydrogel electrolyte.The assembly process of the AISC was greatly simplified,and the displacement and separation of the multilayer structured hydrogel complex were avoided during mechanical deformation.The hydrogel electrolyte with ionic additives exhibited strong adhesion and flexibility,and high ionic conductivity,thereby ensuring the excellent specific capacitance and rate performance of the AISC.The specific capacitances of the AISC were 222.8 mF cm^(−2) at the current density of 0.2 mA cm^(−2) and 151.7 mF cm^(−2) at 3.2 mA cm^(−2).The capacitance retention rate was 68.1%.The energy density of a piece of the device reached 44.6μW h cm^(−2) at a power density of 120.0μW cm^(−2).Moreover,reliable and reproducible energy storage was acquired under bending,compression,and stretching deformations.The AISC was also easily assembled in series to power a light-emitting diode(LED)light.This work provides a facile approach to the construction of flexible supercapacitors for the development of energy storage devices in flexible electronics.展开更多
The uneven deposition of lithium(Li) on current collectors causes serious dendrite growth and volume expansion. Commercial foamed copper(Cu) current collectors are unsuitable for Li anodes because of their large volum...The uneven deposition of lithium(Li) on current collectors causes serious dendrite growth and volume expansion. Commercial foamed copper(Cu) current collectors are unsuitable for Li anodes because of their large volume and mass and lithiophobic nature. Herein, a three-dimensional(3 D) copper@tin(Cu@Sn) nanocone current collector with small volume, light weight, and lithiophilic nature was prepared by a simple electrodeposition method. The synergy of the nanoconical structure and lithiophilic Sn promotes the even deposition of Li and effectively inhibits the formation of Li dendrites. The resultant half batteries exhibit high Coulombic efficiency of 97.6% after 100 cycles at 1 mA cm^(-2), and the symmetrical Li battery demonstrates a prolonged lifespan of over 600 h at 1 mA cm^(-2). The full battery based on organic liquid electrolyte with LiFePO_(4) also exhibits a long lifespan of 550 cycles with high capacity retention of 95.1% at 1 C.Moreover, 3 D Cu@Sn nanocone-based solid-state batteries exhibit excellent electrochemical performance and show no decay after 500 cycles at 1 C. Our work provides a strategy for fabricating 3 D current collectors for high-energy-density Li metal batteries.展开更多
基金Supported by the Nature Science Foundation of Shandong Province under Grant No Y2002A04
文摘Aluminum nitride （AlN） films with h〈100〉 crystalline orientation are fabricated on p-Si （100） substrates at room tempera- ture by pulsed laser deposition. The effects of laser energy density and annealing on the quality of the films are studied by x-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. The crystalline quality of AlN films is improved considerably by increasing the laser energy density while there is increased number of farraginous particles on the surface. The annealing treatment at 600~C produces a recrystallization process in the film, characterized by the improvement of the original crystallinity, the appearance of new crystalline orientations, and the increase of the crystallites. The surface becomes rougher due to the increase of the grain size during annealing.
基金supported by the Natural Science Foundation of Shandong Province(ZR2020KB018)the Natural Science Foundation of Jiangsu Province(BK20190688)+2 种基金the Six Talent Peak Innovation Team in Jiangsu Province(TD-SWYY-009)the"Taishan Scholars"Construction Special Fund of Shandong Provincethe Industrial Alliance Fund of Shandong Provincial Key Laboratory(SDKL2016038)。
文摘Hydrogel systems promote the development of flexible energy storage devices because of their inherent mechanical elasticity and ionic conductivity.However,achieving stable energy storage capacity under violent mechanical deformation is still a challenge for hydrogel devices.In this work,an all-in-one integrated supercapacitor(AISC)was assembled using in situ deposited polyaniline/graphene oxide nanocomposites for both sides of the incorporated ionic hydrogel electrolyte.The assembly process of the AISC was greatly simplified,and the displacement and separation of the multilayer structured hydrogel complex were avoided during mechanical deformation.The hydrogel electrolyte with ionic additives exhibited strong adhesion and flexibility,and high ionic conductivity,thereby ensuring the excellent specific capacitance and rate performance of the AISC.The specific capacitances of the AISC were 222.8 mF cm^(−2) at the current density of 0.2 mA cm^(−2) and 151.7 mF cm^(−2) at 3.2 mA cm^(−2).The capacitance retention rate was 68.1%.The energy density of a piece of the device reached 44.6μW h cm^(−2) at a power density of 120.0μW cm^(−2).Moreover,reliable and reproducible energy storage was acquired under bending,compression,and stretching deformations.The AISC was also easily assembled in series to power a light-emitting diode(LED)light.This work provides a facile approach to the construction of flexible supercapacitors for the development of energy storage devices in flexible electronics.
基金supported by the National Natural Science Foundation of China (51771094 and 21835004)the National Key R&D Program of China (2016YFB0901500)+1 种基金the Ministry of Education of China (B12015 and IRT13R30)Tianjin Natural Science Foundation (18JCZDJC31500)。
文摘The uneven deposition of lithium(Li) on current collectors causes serious dendrite growth and volume expansion. Commercial foamed copper(Cu) current collectors are unsuitable for Li anodes because of their large volume and mass and lithiophobic nature. Herein, a three-dimensional(3 D) copper@tin(Cu@Sn) nanocone current collector with small volume, light weight, and lithiophilic nature was prepared by a simple electrodeposition method. The synergy of the nanoconical structure and lithiophilic Sn promotes the even deposition of Li and effectively inhibits the formation of Li dendrites. The resultant half batteries exhibit high Coulombic efficiency of 97.6% after 100 cycles at 1 mA cm^(-2), and the symmetrical Li battery demonstrates a prolonged lifespan of over 600 h at 1 mA cm^(-2). The full battery based on organic liquid electrolyte with LiFePO_(4) also exhibits a long lifespan of 550 cycles with high capacity retention of 95.1% at 1 C.Moreover, 3 D Cu@Sn nanocone-based solid-state batteries exhibit excellent electrochemical performance and show no decay after 500 cycles at 1 C. Our work provides a strategy for fabricating 3 D current collectors for high-energy-density Li metal batteries.
