OPTICAL MATERIALS
·
2020
·
IF 2.779
Guonan Cui,Yanchun Yang,Ruilan Chen,Chengjun Zhu
Cations substitutions are known to make much significant contribution on achieving the high-quality kesterite Cu 2 ZnSn(S,Se) 4 thin films . And the optimal ratios of Mn, Ni and Co substitutions are reported to be ~0.05, belong to the low doping to reduce their defect density , which looks like to some extent the effect of Na doping. In this study, learning the research experience of alkali metal doping, we introduced the extra trace Mn 2+ ion into the precursor solution without affecting the compositions of other elements (i.e. Cu, Zn, and Sn), and the effect of trace addition on properties of the absorber layer was also studied. It was discovered that crystalline, electrical properties, and hole carrier concentration of Cu 2 ZnSn(S,Se) 4 thin films increased with an increase of Mn incorporation, and the best doping ratio of Mn/(Cu + Zn + Sn) was considered to be 0.03. In addition, the effect of extra trace Mn-doping on the film thickness and elemental compositions of Cu 2 ZnSn(S,Se) 4 absorber layer were studied in detail.
研究领域:
材料科学
·
半导体物理
·
薄膜制备
·
光伏材料
·
固体化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·Vol. 48
·期 22
·33455-33461
·
IF 5.532
Yuyu Liu,Wenye Deng,Xianghui Chen,Yan Xue,Xuelian Bai,Huimin Zhang,Aimin Chang,Yongxin Xie
A series of novel high temperature negative temperature coefficient (NTC) composite ceramics based on (1- x )CaMn 0.05 Zr 0.95 O 3 - x NiMn 2 O 4 ( x = 0, 0.1, 0.2, 0.3) were fabricated by using the solid-state method. The Rietveld refinement method and backscattered electron (BSE) image confirmed the absence of any other phase. The conduction mechanism of the composite ceramics was determined by analyzing the complex impedance and resistance-temperature characteristics, which could be related to the formation of a continuous Mn 3+ -O-Mn 4+ network. The effect of spinel content on the high temperature stability was analyzed using aging tests. The ρ 400°C , ρ 700°C and B 400/700 values of the NTC thermistors were determined to be 4.9 × 10 6 –1.2 × 10 4 , 1.4 × 10 5 –0.8 × 10 3 Ω cm and 12739-5712 K, respectively. This indicated that the electrical properties could be tuned by adjusting the weight ratio of CaMn 0.05 Zr 0.95 O 3 and NiMn 2 O 4 . The findings obtained in this study reveal that the composite NTC thermistor exhibits a good application potential at high temperatures and under harsh environments.
研究领域:
材料科学
·
无机非金属材料
·
电子功能材料
·
固态离子学
·
高温传感器技术
✓ 已验证
DOI
高影响因子
MATERIALS & DESIGN
·
2016
·
IF 3.997
Yanjie Wang,Min Li,Weibang Lu,Yizhuo Gu,Shaokai Wang,Rui Sun,Xuetong Zhang,Qingwen Li,Zuoguang Zhang
A nano-carbon composite, consisting of a graphene aerogel-carbon nanotube (CNT) film, is constructed by coating a strong and flexible CNT film onto the surface of a porous graphene aerogel core. The prepared gradient composite, ultralight and strong, can carry objects more than 15,000 times its own weight, exhibiting impressive compression resistance. Compared to the original graphene aerogel , the composite exhibits 8–9-fold increased values in its elastic modulus and compressive strength at a strain of 20% and an approximately 10-fold increase in electrical conductivities in the axial direction . In addition, the elastic recovery ability after compressive deformation and the ability to preserve liquid are also improved.
研究领域:
材料科学
·
纳米科技
·
复合材料工程
·
生物启发设计
·
力学性能研究
·
功能材料
·
电学性能
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2018
·Vol. 30
·期 2
·1699-1705
·
IF 2.324
Teng Fei,Chen Dong,Ma Yuzhe,Ji Shaohua,Liu Jiaojiao,Wang Tianhua,Tang Jie,Cao Lifeng,Teng Bing
N,N -dimethylamino-4′-N′-methylstilbazolium 2,4,6-trimethylbenzenesulfonate (DSTMS)-graphene ex-situ and in-situ composite films with 2% concentration of graphene were first prepared and systematically investigated. The crystallinity of DSTMS-based composite films were confirmed by XRD analysis, and the functional groups of composite films can be obtained by FT-IR. Optical absorptions were recorded using UV–Vis-NIR spectral analysis, and the band gap and extinction coefficient of the films were calculated. The thermal stability of the composite films were analyzed by TG/DSC. The pressure sensitive resistance test showed that the pressure sensitive signal of the composite films were significantly increased after graphene added, while the signal of DSTMS film eventually disappears. This work expands the application of organic nonlinear crystal DSTMS in optics and electricity by doping graphene.
研究领域:
材料科学
·
凝聚态物理
·
功能材料
·
非线性光学
·
纳米复合材料
·
电学性能
·
光学性能
·
热分析
✓ 已验证
DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2020
·Vol. 221
·期 14
·2000144
·
IF 2.335
Guangfa Shi,Xiaomin Cai,Wenqiang Wang,Gengchao Wang
Polymeric positive temperature coefficient (PTC) materials can be used to install “brake” technology for the thermal runaway of lithium-ion batteries. However, it still has poor cycle stability and obvious negative temperature coefficient (NTC) effect, which reduces the reliability of the material. In order to solve these problems, conductive polymer poly(3,4-ethylenedioxythiophene) (PEDOT) modified multilayer graphene (MLG) conductive additive (PEDOT-MLG) is introduced into middle density polyethylene/carbon black (MDPE/CB) system. Compared with the conventional modification, the PEDOT modified MLG shows high conductivity and excellent thermal stability. In addition, the introduction of PEDOT-MLG into MDPE/CB can further reduce the room temperature resistivity due to the good compatibility between the modified graphene and the matrix, thus improving the PTC intensity to 7.1. What is more, MLG limits the re-aggregation of CB particles when the temperature further rises, which effectively weakens the NTC effect.
研究领域:
高分子材料科学
·
功能材料
·
能源材料
·
纳米复合材料
·
电学性能
·
锂离子电池安全
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）