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31.
Fanbo Meng Mingchang Zhang Jin Huang Wen Feng Lu Jun Min Xue Hao Wang 《Advanced functional materials》2021,31(9):2008280
The development of the Internet of things has prompted an exponential increase in the demand for flexible, wearable devices, thereby posing new challenges to their integration and conformalization. Additive manufacturing facilitates the fabrication of complex parts via a single integrated process. Herein, the development of a multinozzle, multimaterial printing device is reported. This device accommodates the various characteristics of printing materials, ensures high-capacity printing, and can accommodate a wide range of material viscosities from 0 to 1000 Cp. Complete capacitors, inclusive of the current collector, electrode, and electrolyte, can be printed without repeated clamping to complete the preheating, printing, and sintering processes. This method addresses the poor stability issue associated with printed electrode materials. Furthermore, after the intercalation of LiFePO4 with Na ions, X-ray photoelectron spectroscopy and X-ray diffraction results reveal that the Na ions permeate the interlayer structure of LiFePO4, enhancing the ion migration channels by increasing the ion transmission rate. A current rate of 2.5 mAh ensures >2000 charge/discharge cycles, while retaining a charge/discharge efficiency of 96% and a discharge capacity of 91.3 mAh g−1. This manufacturing process can provide conformal power modules for a diverse range of portable devices with various shapes, improving space utilization. 相似文献
32.
Wenyan Ma Lian-Wei Luo Peihua Dong Peiyun Zheng Xiuhua Huang Chong Zhang Jia-Xing Jiang Yong Cao 《Advanced functional materials》2021,31(45):2105027
Recent studies have demonstrated that dihydrophenazine (Pz) with high redox-reversibility and high theoretical capacity is an attractive building block to construct p-type polymer cathodes for dual-ion batteries. However, most reported Pz-based polymer cathodes to date still suffer from low redox activity, slow kinetics, and short cycling life. Herein, a donor–acceptor (D–A) Pz-based conjugated microporous polymer (TzPz) cathode is constructed by integrating the electron-donating Pz unit and the electron-withdrawing 2,4,6-triphenyl-1,3,5-triazine (Tz) unit into a polymer chain. The D–A type structure enhances the polymer conjugation degree and decreases the band gap of TzPz, facilitating electron transportation along the polymer skeletons. Therefore the TzPz cathode for dual-ion battery shows a high reversible capacity of 192 mAh g−1 at 0.2 A g−1 with excellent rate performance (108 mAh g−1 at 30 A g−1), which is much higher than that of its counterpart polymer BzPz produced from 1,3,5-triphenylbenzene (Bz) and Pz (148 and 44 mAh g−1 at 0.2 and 10 A g−1, respectively). More importantly, the TzPz cathode also shows a long and stable cyclability of more than 10 000 cycles. These results demonstrate that the D–A structural design is an efficient strategy for developing high-performance polymer cathodes for dual-ion batteries. 相似文献
33.
Qiushi Huang Chuanhua Li Yuankun Tu Yu Jiang Ping Mei Xuemin Yan 《Ceramics International》2021,47(2):1602-1608
In the development of fuel cells, it is the key to large-scale commercialization of fuel cells to rationally design and synthesize efficient and non-noble metals-based bifunctional electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). In this paper, spinel CoFe2O4/carbon nanotube composites (CoFe2O4/CNTs/FA) were synthesized by solvothermal and calcination method. XRD, TEM, XPS and BET characterizations indicate that the addition of complexing agent fumaric acid can improve the crystal growth kinetics and morphology of CoFe2O4/CNTs nanohybirds. The as-synthesized CoFe2O4/CNTs/FA pyrolyzed at 500 °C have an outstanding bifunctional catalytic activity for ORR and OER with the potential of 1.62V (vs. RHE) at a current density of 10 mA/cm2 and half-wave potential E1/2 = 0.808V (vs. RHE) in alkaline electrolyte, respectively. It is obviously better than unloaded CoFe2O4 nanoparticles and commercial CNTs. CoFe2O4/CNTs/FA also exhibit better methanol tolerance ability and durability than commercial Pt/C and RuO2 catalyst. This investigation broadens an idea of simple compounding of spinel with carbon-based materials to improve electrochemical properties. 相似文献
34.
Wen Cao Zhonghua Zhou Chenyu Li Qun Wang Yue Huang Shirley Shen 《Ceramics International》2021,47(2):1807-1818
Sodalime float (SF) glass is widely used in our societies and industries. Hydrothermal corrosion method is one of the effective ways to prepare a superhydrophobic glass, but there is still lack of knowledge about hydrothermal corrosion behavior and mechanism of SF glass. We have hydrothermally treated SF glass at 180 °C for different time, and tried to reveal the aqueous corrosion process of SF glass. We have characterized the morphologies and chemical compositions of samples, and found that (1) the two sides of SF glass have different corrosion resistances, and (2) a multilayer structural coating with a nanoflake layer (Mg-rich gel layer), a nanowire layer (Ca-rich gel layer), and a porous layer (etched layer) is formed on the air-side of SF glass. Based on the experimental results, we have proposed an aqueous corrosion mechanism of SF glass. The insights of the hydrothermal corrosion behaviors and mechanism provide helpful guidelines to glass surface structural control and functionalization. 相似文献
35.
Yu-Xuan Li Ping Li Yu-Zhe Wu Zhen-Liang Xu Ming-Ling Huang 《Ceramics International》2021,47(2):2180-2186
A novel TiO2 thin film was prepared on the ceramic hollow fiber by the sol-gel method using poly(vinylpyrrolidone) (PVP) and polyvinyl alcohol (PVA) as additives. SEM images verified the formation of TiO2 layer with various thickness using different composition of titania sols. The effect of the PVP and PVA contents on the TiO2 sol properties, the separation and the antifouling performance of the ultrafiltration membranes were investigated thoroughly. When the contents of PVP and PVA were 1.0 wt% and 0.8 wt%, respectively, the resultant membrane showed a thickness of 0.55 μm with a pure water flux of 255 L m?2 h?1. In addition, the adherent foulant bovine serum albumin was applied to evaluate the antifouling performance. During the three fouling-recovery cycles, the flux recovery ratio and the flux decay ratio maintained about 99% and 30%. The BSA flux and rejection were still 169 L m?2 h?1 and 96.9% after the cycles, indicating a superior antifouling property. 相似文献
36.
Catalysis Letters - The production of H2 from non-fossil sources is a key research challenge to contributing solving the forthcoming energy problem. Aqueous solutions of tetrahydroxydiboron have... 相似文献
37.
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39.
Applied Intelligence - With the development of sensor and communication technology, industrial systems have accumulated a large amount of data. This data has provided new perspectives and methods... 相似文献
40.