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111.
《Journal of the European Ceramic Society》2022,42(15):6985-6996
Dielectric energy storage capacitors have been explored to obtain excellent energy storage density along with high energy storage efficiency with the development of electronic devices. In this work, linear dielectric CaTi0.5Zr0.5O3 is introduced into Bi0.5Na0.5TiO3-NaNbO3 matrix to form 0–3 type composites to vary the size and conductivity of the composite grain, which lead to ultra-high breakdown electric field of 410 kV/cm and the quasi-linear hysteresis loops. Meanwhile, linear dielectric does not change the characteristic of ferroelectric, and thus composites maintain high maximum polarization of 26.4 μC/cm2. Integrating the advantages of linear dielectric and ferroelectric, an excellent recoverable energy density of 4.93 J/cm3 with an efficiency of 93.3% have been achieved in BNT-NN/7 wt%CZT ceramics. This work contributes to the development of dielectric energy storage capacitors for practical applications in pulsed power devices. 相似文献
112.
《Journal of the European Ceramic Society》2022,42(1):119-128
Aurivillius ferroelectrics, Ca0.92-x(Na0.5Bi0.5)x(Na0.5Ce0.5)0.08Bi2Ta2O9 (CNCBT-NBT100x, x = 0, 0.02, 0.04, 0.06, 0.08, 0.10, 0.20, 0.30 and 0.40) ceramics were prepared by conventional electroceramic processing procedures. The novel Aurivillius ferroelectrics possess a gradual improving piezoelectricity (d33max～12.8 pC/N) and ferroelectricity (Prmax～7.4 μC/cm2) with the introduction of (Na0.5Bi0.5)2+ content. Moreover, the addition of (Na0.5Bi0.5)2+ also improves the temperature stability of piezoelectric activity obviously. The d33 of CNCBT-NBT40 maintains 94% of its initial stage even the annealing temperature reaching at 900 °C. The TC of CNCBT-NBT100x exhibits a decreasing trend with the increasing doping concentration, but CNCBT-NBT40 still possesses a high TC (TC～924.9 °C). The high-temperature electrical resistivity of CNCBT-NBT100x almost remains unchanged owing to the close band-gap energy, and the ρ of CNCBT-NBT40 is above 6 × 106 Ω?cm at 600 °C. This work may provide a new way of designing the doping formula to improve comprehensive properties of Aurivillius ferroelectrics. 相似文献
113.
《International Journal of Hydrogen Energy》2023,48(58):22141-22160
Energy storage systems are increasingly used as part of electric power systems to solve various problems of power supply reliability. With increasing power of the energy storage systems and the share of their use in electric power systems, their influence on operation modes and transient processes becomes significant. In this case, there is a need to take into account their properties in mathematical models of real dimension power systems in the study of various operation modes, design, etc. In this article the main types of energy storage devices, as well as the fields and applications of their use in electric power systems are considered. The principles of realization of detailed mathematical models, principles of their control systems are described for the presented types of energy storage systems. The article is an overview and can help in choosing a mathematical model of energy storage system to solve the necessary tasks in the mathematical modeling of storage systems in electric power systems.Information is presented on large hydrogen energy storage units for use in the power system. 相似文献
114.
《Ceramics International》2023,49(19):31006-31011
Multimodal luminescence has emerged as a promising solution in the realm of anti-counterfeiting techniques, which have gained global attention due to their association with information and data security. The conventional approach to achieving multimodal luminescence typically involves combining upconversion and downshifting luminescence, which necessitates the use of external excitation sources and costly detection equipment. Herein, we develop an anti-counterfeiting strategy based on the afterglow performance of NaLuF4: Gd, Tm nanoparticles after X-ray excitation. The X-ray-induced Frenkel defects-base traps ensnare electrons with low kinetic energy, resulting in the creation of persistent photon traps that are responsible for the temperature-dependent afterglow intensity. The dual-band and thermo-enhanced afterglow emission can encrypt information well according to our proof-of-concept experiment and the visible light signal can be successfully captured by a smartphone camera. These unique features of NaLuF4: Gd, Tm nanoparticles render them highly appealing for multilevel anti-counterfeiting applications. 相似文献
115.
Yong-Chun Ye Li Chen Xian-Min Chen Chun-Ying Ma Bing-Hao Lv Jiang-Ying Wang Wei-Dong Dou Chu Zhang Ting-Li Ma Jian-Xin Tang 《Advanced functional materials》2024,34(8):2310136
Tin oxide (SnO2) is currently the dominating electron transport material (ETL) used in state-of-the-art perovskite solar cells (PSCs). However, there are amounts of defects distributed at the interface between ETL and perovskite to deteriorate PSC performance. Herein, a molecule bridging layer is built by incorporating 2,5-dichloroterephthalic acid (DCTPA) into the interface between the SnO2 and perovskites to achieve better energy level alignment and superior interfacial contact. The multifunctional molecular bridging layer not only can passivate the trap states of Sn dangling bonds and oxygen vacancies resulting in improved conductivity and the electron extraction of SnO2 but also can regulate the perovskite crystal growth and reduce defect-assisted nonradiative recombination due to its strong interaction with undercoordinated lead ions. As a result, the DCTPA-modified PSCs achieve champion power conversion efficiencies (PCEs) of 23.25% and 20.23% for an active area of 0.15 cm2 device and 17.52 cm2 mini-module, respectively. Moreover, the perovskite films and PSCs based on DCTPA modification show excellent long-term stability. The unencapsulated target device can maintain over 90% of the initial PCE after 1000 h under ambient air. This strategy guides design methods of molecule bridging layer at the interface between SnO2 and perovskite to improve the performance of PSCs . 相似文献
116.
《International Journal of Hydrogen Energy》2022,47(66):28303-28312
Oxygen evolution reaction (OER) catalysts with highly efficient and cost-effective are cardinal for hydrogen production through water electrolysis. Herein, a novel strategy based on the theory of molecular crystallization and atomic diffusion is described to construct the FeOOH@Ni3(NO3)2(OH)4/NF. It requires an overpotential of 248 mV at the current density of 100 mA cm?2 for OER. The in-situ Raman spectroscopy test exploring the catalytic actives unravels that NiOOH is one of the real active species and a small amount of NiFe2O4 is generated during OER process. The analysis of the mechanism shows that NiOOH converted from the intermediate product of Ni(OH)2 derived from Ni3(NO3)2(OH)4 in the process of OER. NiOOH and FeOOH mainly work together contributing to boosting intrinsic catalytic activity. This work may provide a new insight into fabricating strategy for other nano-catalysts. The in-situ Raman measurement provides a valid and reliable means to probe into the catalytic active site and catalytic mechanism in the catalytic process. 相似文献
117.
Mengyao Tang Qiaonan Zhu Pengfei Hu Li Jiang Rongyang Liu Jiawei Wang Liwei Cheng Xiuhui Zhang Wenxing Chen Hua Wang 《Advanced functional materials》2021,31(33):2102011
Aqueous zinc-ion batteries (ZIBs) are a promising candidate for fast-charging energy-storage systems due to its attractive ionic conductivity of water-based electrolyte, high theoretical energy density, and low cost. Current strategies toward high-rate ZIBs mainly focus on the improvement of ionic or electron conductivity within cathodes. However, enhancing intrinsic electrochemical reaction kinetics of active materials to achieve fast Zn2+ storage has been greatly omitted. Herein, for the first time, stable radical intermediate generation is demonstrated in a typical organic electrode material (methylene blue [MB]), which effectively decreases the reaction energy barrier and enhances the intrinsic kinetics of MB cathode, enabling ultrafast Zn2+ storage. Meanwhile, anionic co-intercalation essentially avoids MB molecules rearranging their configuration and sharing Zn2+ with adjacent functional groups, thus keeps the structure stable. As a result, Zn–MB batteries exhibit an excellent rate capability up to 500C and ultralong life of 20 000 cycles with a negligible 0.07% capacity decay per cycle at 100C, which is superior to that of most reported aqueous ZIBs batteries. This work provides a novel strategy of stable radical chemistry for ultrafast-charging aqueous ZIBs, which can be introduced to other appropriate organic materials and multivalent ion battery systems. 相似文献
118.
《International Journal of Hydrogen Energy》2021,46(59):30344-30354
Excellent light harvest, efficient charge separation and sufficiently exposed surface active sites are crucial for a given photocatalyst to obtain excellent photocatalytic performances. The construction of two-dimensional/two-dimensional (2D/2D) or zero-dimensional/2D (0D/2D) binary heterojunctions is one of the effective ways to address these crucial issues. Herein, a ternary CdSe/WS2/g-C3N4 composite photocatalyst through decorating WS2/g-C3N4 2D/2D nanosheets (NSs) with CdSe quantum dots (QDs) was developed to further increase the light harvest and accelerate the separation and migration of photogenerated electron-hole pairs and thus enhance the solar to hydrogen conversion efficiency. As expected, a remarkably enhanced photocatalytic hydrogen evolution rate of 1.29 mmol g−1 h−1 was obtained for such a specially designed CdSe/WS2/g-C3N4 composite photocatalyst, which was about 3.0, 1.7 and 1.3 times greater than those of the pristine g-C3N4 NSs (0.43 mmol g−1 h−1), WS2/g-C3N4 2D/2D NSs (0.74 mmol g−1 h−1) and CdSe/g-C3N4 0D/2D composites (0.96 mmol g−1 h−1), respectively. The superior photocatalytic performance of the prepared ternary CdSe/WS2/g-C3N4 composite could be mainly attributed to the effective charge separation and migration as well as the suppressed photogenerated charge recombination induced by the constructed type-II/type-II heterojunction at the interfaces between g-C3N4 NSs, CdSe QDs and WS2 NSs. Thus, the developed 0D/2D/2D ternary type-II/type-II heterojunction in this work opens up a new insight in designing novel heterogeneous photocatalysts for highly efficient photocatalytic hydrogen evolution. 相似文献
119.
《能源学会志》2020,93(3):962-976
The CO2 gasification reactivity of pine sawdust chars (PS char) obtained from the different high-temperature pyrolysis is studied based on non-isothermal thermogravimetric method. Results show that the order of gasification reactivity is PS char-1073 > PS char-1273 > PS char-1473. Under the effect of high-temperature pyrolysis, the surface structure of biomass char is gradually destroyed and the pore structure parameters of specific surface area, total pore volume and average pore diameter increase. By means of the N2 adsorption-desorption isotherms, it is seen that biomass char has more micro- and mesoporous at higher pyrolysis temperature. Besides, the PS char-1073 mostly has rich closed cylinder pores and parallel plate pores, and the PS char-1273 and PS char-1473 have plentiful open cylinder pores and parallel plate pores. An increase of pyrolysis temperature contributes to the development of porosity and improves diffusion path, which promotes the gasification reactivity. But, its effect on the decline of active site hinders the gasification reactivity. What's more, the kinetic model of distributed activation energy model (DAEM) is applied to calculate activation energy and pre-exponential factor with the integral and differential methods. The calculation results of integral method is more accurate and precise because the differential method is more sensitive than integral method for experimental noise. There is a compensation effect in the CO2 gasification process. 相似文献
120.
《International Journal of Hydrogen Energy》2020,45(11):6885-6896
Mixed metal sulfides with high specific capacitances and superior rate capabilities can meet the need of new materials for technological advancement of energy storage systems. We demonstrate in this study a facile fabrication of microspheres-like NixMny sulfides with different molar ratios of metallic salts through a one-step solvothermal route. The hierarchical NixMny sulfides-based compounds feature spherical architectures with relatively rough surfaces and assembled from ultrasmall and self-aggregated nanoprimary crystals. Especially, the NixMny sulfide (x/y = 1:1) presents an excellent battery-like performance with a high specific capacitance (219.4 mAh g−1 at current density of 1 A g−1) and a good rate capability (123 mAh g−1 at 50 A g−1), benefiting from the greatly improved faradaic redox processes boosted by the synergistic effect of Ni and Mn electroactive components and as well as fast mass transfer. Furthermore, the as-fabricated asymmetric supercapacitor based on NixMny sulfide (x/y = 1:1) presents a maximum energy density of 34 W h kg−1 at a power density of 868.1 W kg−1 with both superior rate and long-term cycling stabilities. In view of low cost and improved electrochemical performance, such integrated compound proposes a new and feasible pathway as a potential electrode configuration for energy storage devices. 相似文献