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排序方式: 共有621条查询结果,搜索用时 453 毫秒
1.
Huimin Zhao Wensi Wang Yunmei Du Yu Yang Minghui Wang Shaoxiang Li Ruixin Chen Yanru Liu Lei Wang 《International Journal of Hydrogen Energy》2021,46(18):10763-10772
In this work, we synthesized Se doped MoS2@Ni3S2 with nanosheets coated nanorods structure supported on Ni foam (MoNiSeS). Firstly, MoS2@Ni3S2 (MoNiS) nanorods was synthesized by hydrothermal method. After selenization treatment, MoSe2 successfully formed on the edge of MoS2 nanosheets and particle Ni3S2 transformed into NiSe, in which MoSe2 and NiSe acted as new phase in MoNiSeS. The obtained MoNiSeS only needs a low overpotential of 68 mV to reach the current density of 10 mA cm?2, and has a low Tafel plots of 72.77 mV dec?1 and good electrochemical durability, whose electrochemical activity is much better than that of MoNiS and NiSeS, implying the introduction of Mo and Se is beneficial to improve the electrocatalytic performance of NiS for HER. In addition, the proper amount of Mo source, which has an effect on the morphology of product, has also been investigated. For MoNiSeS, the typical nanosheets coated nanarods expose more active sites and the synergic effects is good to the improvement of the catalytic activity. Meanwhile, WNiSeS has also been prepared using the same method and the corresponding results show that the electrochemical activity of WNiSeS is much better than that of NiSeS, proving the universality of this strategy. 相似文献
2.
描述了ZnSxSe1-x光盲紫外液晶光阀的结构和工作原理 ,并从器件的电学模型出发 ,着重讨论了整体器件对ZnSxSe1-x光敏层的特殊要求。采用分子束外延技术在ITO导电玻璃上制备了具有 (111)面定向生长结构的ZnSxSe1-x多晶薄膜 ,通过控制反应时的生长参数 ,制备出了符合器件设计要求的光敏层薄膜。室温下 ,该薄膜的紫外 /可见光响应对比度大于10 3 ;响应波长截止边可通过控制薄膜中的Se组分 ,在 (36 0~ 4 10 )nm范围内连续可调 ;薄膜的暗电阻率在 (4 32× 10 9~ 2 0 3×10 11)Ω·m之间 ,并随着晶粒的增大而减小 ;在液晶光阀工作的低频段 (<2 0 0Hz) ,其光 /暗阻抗比在 0 2 2~ 0 36之间。 相似文献
3.
The employment of the Zn(Se,Te) pseudo-graded contacting scheme to p-type ZnSe-based alloys contributes directly to the recent
demonstration of room temperature continuous-wave operation of II– VI green-blue laser diodes. Contact ohmicity is maintained
down to cryogenic temperatures which enabled the investigation of electrical transport properties associated with the p-type
nitrogen-doped ZnSe, Zn(S,Se), and (Zn,Mg)(S,Se). The observation of both persistent photoconductivity and a metastable population
of holes which are in thermodynamic equilibrium with hydrogenic acceptors having reduced activation energy suggests the presence
of a DX-like behavior for holes in p-type (Zn,Mg)(S,Se). 相似文献
4.
A. Amara A. Ferdi A. Drici J.C. Bernde M. Morsli M. Guerioune 《Catalysis Today》2006,113(3-4):251-256
Co-evaporation technique from three sources was used to prepare Cu(In, Ga)Se2 polycrystalline thin films for photovoltaic conversion. Their conductivity was studied in the range 20–300 K. The grain boundary scattering mechanism is mainly responsible for the diffusion process in the latter materials. In the low temperature region, we interpret the data in terms of Mott law and the analysis is very consistent with the variable range hopping. However, thermoionic emission is predominant at high temperatures. When the conductivity deviates from the classical grain boundary conduction models, inhomogeneity is then considered and parameters such as the standard deviation and the mean potential barrier height are derived. Transmittance measurements yielded band gap values of 1.07 and 1.64 eV for CuInSe2 and CuGaSe2, respectively. 相似文献
5.
采用连续离子层吸附反应(SILAR)法,分别用含有Se2-,Bi3+和Sb3+的离子溶液作为独立的阴、阳离子前驱溶液,以载玻片为衬底,在室温下沉积出致密且具有镜面金属光泽的Bi2Se3-Sb2Se3薄膜材料.为了改善薄膜样品的结晶状态,对其进行了退火处理.用AFM观察了薄膜样品的表面形貌,用XRD分析了退火前后薄膜样品的结晶状态.结果表明薄膜样品经200℃较低温度下退火处理4 h以后,薄膜的结晶状态由无定形态转化为多晶态,其平均晶粒尺寸为30 nm~40 nm. 相似文献
6.
由于锂资源的价格逐渐攀升,亟需开发价格低廉的电池系统。通过共沉淀法合成FeCoNiCP片状前驱体,再经过包覆多巴胺、退火和在氮气下硒化,制备钠离子电池负极材料Fe3Se8/Co3Se4/NiSe2/NC。在0.01~3.00 V充放电,以0.1 A/g的电流循环70次,电极仍有468.38 mAh/g的可逆比容量;在0.1 A/g、0.2 A/g、0.5 A/g、1.0 A/g、2.0 A/g和5.0 A/g的电流下,分别具有363.85 mAh/g、345.88 mAh/g、320.73 mAh/g、308.31 mAh/g、290.33 mAh/g和249.29 mAh/g的可逆比容量。Fe3Se8/Co3Se4/NiSe2/NC复合材料较好的电化学性能,可归因于碳导电网络、多金属硒化物和独特的纳米结构的协同作用,缓解了充放电过程中的体积膨胀。 相似文献
7.
Lin Mei Jiantie Xu Zengxi Wei Huakun Liu Yutao Li Jianmin Ma Shixue Dou 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(34)
With the large‐scale applications of electric vehicles in recent years, future batteries are required to be higher in power and possess higher energy densities, be more environmental friendly, and have longer cycling life, lower cost, and greater safety than current batteries. Therefore, to develop alternative electrode materials for advanced batteries is an important research direction. Recently, the Chevrel phase Mo6T8 (T = S, Se) has attracted increasing attention as electrode candidate for advanced batteries, including monovalent (e.g., lithium and sodium) and multivalent (e.g., magnesium, zinc and aluminum) ion batteries. Benefiting from its unique open crystal structure, the Chevrel phase Mo6T8 cannot only ensure rapid ion transport, but also retain the structure stability during electrochemical reactions. Although the history of the research on Mo6T8 as electrodes for advanced batteries is short, there has been significant progress on the design and fabrication of Mo6T8 for various advanced batteries as above mentioned. An overview of the recent progress on Mo6T8 electrodes applied in advanced batteries is provided, including synthesis methods and diverse structures for Mo6T8, and electrochemical mechanism and performance of Mo6T8. Additionally, a briefly conclusion on the significant progress, obvious drawbacks, emerging challenges and some perspectives on the research of Mo6T8 for advanced batteries in the near future is provided. 相似文献
8.
Ren Wuyang Li Handong Gao Lei Li Yong Zhang Zhongyang Long Chengjia Ji Haining Niu Xiaobin Lin Yuan Wang Zhiming 《Nano Research》2017,10(1):247-254
Nano Research - Thermal transport in superlattices is governed by various phonon-scattering processes. For extracting the phonon-scattering contribution of hetero-interfaces in chalcogenide... 相似文献
9.
通过两步法成功合成了Ag2Se/Se/SiO2纳米复合物。首先采用Na2SiO3和Na2SeSO3为反应物,制得纳米Se/SiO2前驱物,然后将前驱物与AgNO3反应制得产物。讨论了产物的形成机理,利用TEM、XRD、UV-vis、FT-IR、LRS、PL等方法对产物进行了表征,并对产物的电化学和电致发光特性进行了研究。结果表明,产物有一定的电化学活性,并有较好的电致发光行为。 相似文献
10.