MATERIALS CHEMISTRY AND PHYSICS
·
2022
·
IF 4.778
Juguo Dai,Lili Luo,Xiaohong Wang,Long Xia,Hongmei Xie,Chunying Yang,Ruipan Wang,Yiting Xu,Lizong Dai
Nowadays, energy conversion devices have gradually gained attention while vigorously developing clean energy. Carbon materials are promising candidates for supercapacitors , but two issues have plagued the researchers. 1) Does the cation radius in the neutral electrolyte significantly impact the electrochemical performance of carbon materials? 2) How to introduce heteroatoms while constructing hollow structures in carbon spheres. This work proposes a facile template free strategy that uses aniline and pyrrole as nitrogen sources to synthesize carbon sphere precursors. High-temperature carbonization combined with alkali treatment leads to the formation of N-doped hollow porous carbon spheres. Robust wall structure (thickness is about 60–80 nm) and ideal surface structure (the specific surface area is 1079.9 m 2 g −1 ) endow the carbon spheres with excellent electrochemical performance and outstanding cycle stability. The specific capacitance of the carbon spheres in Li 2 SO 4 and Na 2 SO 4 electrolytes under negative working potential (−0.8–0 V) are 378.4 and 367.6 F g −1 , respectively, at a current density of 1 A g −1 . After 5000 cycles, the capacitance retentions are 87.1% and 94.8% in Li 2 SO 4 and Na 2 SO 4 electrolytes. We inferred that the cation radius has a negligible effect on the specific capacitance of carbon materials, but has a more significant effect on the cycling stability and capacitance rate performance. It is hoped that this work can provide a reference for the subsequent construction of N-doped hollow carbon spheres and reasonable selection of electrolytes.
研究领域:
材料科学
·
电化学
·
纳米能源
·
功能材料
·
储能技术
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·Vol. 46
·期 3
·2845-2852
·
IF 3.45
Quansheng Wu,Quan Zhao,Penghui Zheng,Wenbo Chen,Dongfeng Xiang,Ziyu He,Qiang Huang,Jianyan Ding,Jiangcong Zhou
Lithium-containing silicate compounds have attracted so much attention in recent years for applications in energy storage and illumination source due to their rigid structure and good electrical conductivity . In this study, a Eu 3+ doped lithium-containing silicate red phosphor , Li 2 Ca 4 Si 4 O 13 :Eu 3+ , was explored by using structural computational simulations and systematic experiments for multifunctional applications. As a result, due to the quite non-central symmetry of the Ca 2+ sites (C 1 symmetry), the strong 4f-4f excitations in near ultraviolet region were observed. Under near ultraviolet and cathode ray light excitation , Li 2 Ca 4 Si 4 O 13 :Eu 3+ phosphor has an efficient red emission with good thermal stability and ageing resistance. Furthermore, Li 2 Ca 4 Si 4 O 13 :Eu 3+ phosphor exhibits a concentration-sensitive behavior induced by the change of site symmetry. The results show that it is feasible to develop near-ultraviolet and cathode ray light excited red phosphors in lithium-containing silicate compounds.
研究领域:
材料科学
·
无机化学
·
固体物理
·
光电功能材料
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发光材料
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2018
·
IF 2.873
Wenjie Lin,Weiliang Wu,Jie Bao,Zongtao Liu,Kaifu Qiu,Lun Cai,Zhirong Yao,Youjun Deng,Zongcun Liang,Hui Shen
The dopant-free back contact solar cells are demonstrated based on hole selective contact material, chromium trioxide (CrO x , x < 3) with a low melting point for high stability and high performance. In this contribution, CrO x is first applied in silicon based solar cell as the emitter. Integrating 5 nm CrO x and 2 nm LiF x into solar cell as the emitter and the back surface filed, resulted in a device efficiency of 13.6%. For further improvement, the back contact solar cell reaching an efficiency of 15.8% was fabricated, by implementing the multilayer films of CrO x (5 nm)/Au (4 nm)/ CrO x (5 nm) as the emitter. The formation of Cr(OH) 3 in ambient condition, resulted in a lower work function (4.8 eV) of the CrO x film. Furthermore, the multilayer back contact solar cell demonstrated a high stability due to CrO x covered with 500 nm Ag, when stored in ambient air longer than 170 days.
研究领域:
材料科学
·
光伏技术
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半导体器件
·
表面工程
·
能源材料
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Yaping You,Ya Zheng,Zesheng Pan,Yunluo Wang,Tianrui Zhou,Minghui Wang,Haijie Chen,Wan Jiang,Lianjun Wang
White light-emitting diode (WLED) has been widely used as solid-state lighting in recent years, with the advantages of energy saving, high luminous efficiency , and safety. Red phosphors are crucial to the color rendering index of WLED, and Eu 3+ -activated red phosphors can significantly improve the chromaticity performance of WLED. In this work, a series of new orange-red emitting BaLiZn 3 (PO 4 ) 3 : Eu 3+ phosphors were synthesized through high-temperature solid-state reaction method. The phase composition , crystal structure, morphology and photoluminescence properties of BaLiZn 3 (PO 4 ) 3 : Eu 3+ samples were investigated. The phosphors can be effectively excited by the violet light at 394 nm and emit orange-red lights corresponding to the electric dipole transition (5D 0 →7F 1 ) at 594 nm. The optimal doping concentration of Eu 3+ ions was about 5 mol%. The concentration quenching was caused by the electric dipole-dipole interaction between Eu 3+ ions. Temperature-dependent PL spectra indicate that BaLiZn 3 (PO 4 ) 3 : Eu 3+ has excellent emission and color stability at high temperatures. The color coordinates were calculated and fall in the orange-red luminescent area. The color purity is about 98.3 %, and the correlated color temperature is 1710K. These results indicate that the new orange-red phosphor BaLiZn 3 (PO 4 ) 3 : Eu 3+ has potential application prospects in WLED.
研究领域:
材料科学
·
发光材料
·
固体照明
·
无机化学
·
光电子学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·Vol. 50
·期 6
·9753-9761
·
IF 5.2
Li Li,Haoliang Yang,Yongjie Wang,Faling Ling,Xianju Zhou,Guotao Xiang,Zhongmin Cao,Sha Jiang,Zhiyu Yang,Yongbin Hua
Novel Ca 2 ScNbO 6 (CSNO): Cr 3+ phosphors were synthesized through a solid-phase method. The crystal structures, luminescence performances, and applications were introduced in this work. The optimized doping concentration was found with a Cr 3+ concentration of 0.01 mol. Under the 336 nm excitation, the recorded photoluminescence spectrum in the range of 650–1300 nm indicated that the obtained sample can emit a broad near-infrared emission with a dominant peak of 858 nm while the full width at half maximum (FWHM) was determined to be 191 nm. To gain a deeper comprehension of the luminescent properties, the crystal field strength was investigated as Dq/B = 2.03, and the electron-phonon coupling for parameter S was calculated to be about 2.01. As for the potential application, utilizing the variable temperature decay lifetime technique, the relative sensitivity (S R ) was approximately 1.16% K −1 at 387 K, which can be promised for utilization in optical temperature measurement. On the other hand, a near-infrared phosphor-converted lighting-emitting diode ( Pc -LED) was fabricated for night vision. Eventually, the security ink based on the obtained sample was made for use in the anti-counterfeiting field.
研究领域:
材料科学
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光学工程
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无机化学
·
功能材料
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生物医学工程
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Yaoliang Huang,Yunru Zhang,Guizhi Yuan,Dingshan Ruan,Xinlong Zhang,Weijian Liu,Zhongshuai Zhang,Xiaoyuan Yu
Ni/Mn-based layered oxides have been widely studied for sodium ion battery cathode because of high capacity and simple preparation. However, its application has been restricted owing to unstable structure and poor cycling performance. Herein, the multi-element doped hexagonal sheet Ni/Mn-based layered oxide with ZrO 2 surface modification O3-NaNi 0.3 Mn 0.5-x Fe 0.1 Cu 0.1 Zr x O 2 @ZrO 2 (NFMCZ-x) cathode materials have been successfully synthesize by high temperature calcination method accompanied by ball milling activation. XRD refinement results show Zr 4+ substitution of Mn 3+ can increase interlayer distance of sodium layer. Benefiting from the synergetic effect of multi-element doping and ZrO 2 surface modification, the optimized NFMCZ-0.03 sample exhibits a higher discharge capacity of 178 mAh/g at 0.1C and good capacity retention (77 % after 50 cycles at 2C). Furthermore, NFMCZ-0.03 has an excellent air stability with a capacity retention rate of 86 % during 50 cycles at 1C after being exposed in the air for 20 days. The ex-situ XRD results of NMFC at different charge/discharge voltages show Zr 4+ doping can suppress O3 + P3′'–O3′-O3 + P3′' phase transition during charge/discharge process. These results confirm that synergistic effect of multi-doping combined with surface modification can improve electrochemical performance of layered oxides cathodes, which provides a research idea for development of Ni/Mn-based layered oxides cathodes for sodium-ion batteries.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
固态化学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2019
·
IF 5.383
Aijia Wei,Wen Li,Qian Chang,Xue Bai,Rui He,Lihui Zhang,Zhenfa Liu,Yanji Wang
Mg 2+ /F − co-doped LiNi 0.5 Mn 1.5 O 4 cathode material was synthesized by a facile one-step solid-state process. The effect of Mg 2+ /F − co-doping on grain morphology, phase structure, and electrochemical properties was studied by a series of characterizations. Scanning-electron-microscopy images show that Mg 2+ /F − co-doped LiNi 0.5 Mn 1.5 O 4 (denoted LNMO-MF) particles grow larger than pure LiNi 0.5 Mn 1.5 O 4 particles. X-ray diffraction, Raman spectra , Fourier transformation infrared spectroscopy , X-ray photoelectron spectroscopy, and cyclic-voltammetry tests indicate that all samples mainly display a Fd -3m space group and more Mn 3+ ions in the LNMO-MF sample after Mg 2+ /F − co-doping, which is conducive to increasing the cationic disorder degree and enhancing the electronic conductivity of electrode material. Results show that the LNMO-MF cathode material delivers an excellent rate performance with discharge capacities of 142, 144, 140 136, 132, 124, 115, and 100 mAh g −1 at 0.2, 0.5, 1, 2, 3, 5, 7, and 10C (1C = 140 mAh g −1 ), respectively. Remarkably, LNMO-MF also shows cycling stability with a capacity retention of 86.2% at 5C after 400 cycles, which is much higher than that of pure LiNi 0.5 Mn 1.5 O 4 (67.7%). The improvement of LNMO-MF's electrochemical properties could be ascribed to the Mg 2+ /F − co-doping, delivering a more stable structure, better crystallinity , the highest Li + diffusion coefficient , and the lowest charge-transfer resistance.
研究领域:
材料科学
·
电化学
·
无机非金属材料
·
能源存储
·
锂离子电池
·
固态化学
·
功能材料
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2023
·
IF 5.4
Zhihao Zhang,Huimin Li,Ran Pang,Wenjing Wang,Da Li,Lihong Jiang,Su Zhang,Hongjie Zhang
Phosphor-converted light emitting diodes (pc-LEDs) are essential for current lighting and display areas because of their unique properties of being uncomplicated, durable and economical. In previous studies, Pr 3+ doped red-emitting phosphors have attracted enormous research interest due to their high color purity. However, their photoluminescence excitation (PLE) spectra are always hard to be combined with LED chips. This mismatch is a great obstacle to achieve Pr 3+ phosphors utilizing in LED devices. Here, to circumvent this issue, Pr 3+ -doped Ca 3 MgTiGe 3 O 12 (CMTG) red-emitting phosphor was optimized with PLE band shifting from 330 nm to 360 nm after tuning with Bi 3+ co-doping based on the structure and phosphorescence properties. The chip-matched excitation makes it a good candidate for white LEDs (wLEDs) fabrication to improve the output quality of device. Meanwhile, the high color purity of 93.02 % was obtained, which is conducive to widening the color gamut of backlight display applications. The photoluminescence (PL) spectra, fluorescence lifetime, and X-ray photoelectron spectroscopy (XPS) analysis were employed and discussed in detail to explain the role of Bi 3+ played in the system. Finally, wLEDs were fabricated with CMTG:Pr 3+ , Bi 3+ , showing a high color rendering index (Ra) of 94.4. And the color gamut covers ∼80 % of the National Television System Committee (NTSC) standard, suggesting great potential for applications of wLEDs and backlight display.
研究领域:
材料科学
·
发光材料
·
固态照明
·
显示技术
·
无机化学
·
光电子学
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2023
·Vol. 129
·期 11
·794
·
IF 2.7
Wang Xuekai,Cao Yongze,Yan Xianglan,Li Lei,Zhang Xizhen,Zhang Jinsu,Chen Baojiu
17K 2 O–33SnO–50P 2 O 5 –xMnCl 2 glasses with x = 0, 0.6, 1.2, 1.8, 2.4, 3.0 were made using melt quenching at 500 °C low temperature. The structure and photoluminescence properties of these glasses were investigated, and the water resistance was evaluated. The experimental results show that the effectively energy transfer from Sn 2+ to Mn 2+ occurs, and when Mn 2+ doping at 3.0, the energy transfer efficiency reaches 74%. Under 340 nm excitation, the emission wavelength is in the range of 500–800 nm, covering the absorption wavelength of chlorophyll P R and P FR , which indicates that the low temperature glasses can be used for plant cultivation. This glass material was immersed in water for 24 h, and the luminescence intensity decreases 10%. This indicates that the glass material has certain waterproof property.
研究领域:
材料科学
·
农业光学
·
无机非金属材料
·
光生物学
·
功能玻璃
✓ 已验证
DOI
高影响因子
Science China-Materials
·
2018
·Vol. 61
·期 9
·1209-1217
·
IF 4.318
Sun Fu-Hua,Dong Jinfeng,Dey Shaugath,Asfandiyar,Wu Chao-Feng,Pan Yu,Tang Huaichao,Li Jing-Feng
Cu 12 Sb 4 S 13 tetrahedrite has received great attention as an earth-abundant and environmental-friendly thermoelectric material. This work aims to uncover the thermoelectric performance-enhancing effect and the mechanism of nickel doping on tetrahedrite. A series of Cu 12− x Ni x Sb 4 S 13− δ ( x = 0.5, 0.7, 1.0, 1.5 and 2.0) compounds were synthesized by mechanical alloying combined with spark plasma sintering. It is found that the thermal conductivity sharply reduces with increasing Ni content over the entire temperature range, < 0.9 W m −1 K −1 , accompanied with an enhanced thermoelectric power factor. The model predicted that the reduced lattice thermal conductivity is attributed to mid-frequency phonon scattering, caused by precipitates and dislocations resulting from Ni doping. Consequently, a high ZT value up to 0.95 at 723 K was achieved for Cu 11 NiSb 4 S 13− δ , corresponding to a ∼46% increase over non-doped Cu 12 Sb 4 S 13− δ . Furthermore, the cyclic measurement showed that the Ni-doped tetrahedrites displayed high chemical stability.
研究领域:
材料科学
·
热电材料
·
无机化学
·
固体物理
·
能源材料
✓ 已验证
DOI
高影响因子
Laser & Photonics Reviews
·
2023
·Vol. 18
·期 1
·2300732
·
IF 11
Zhuowei Li,Ge Zhu,Shanshan Li,Wen Xu,Qingfeng Bian,Yan Cong,Ming He,Xixian Luo,Shuangyu Xin,Bin Dong
The burgeoning phosphor-converted near-infrared light-emitting diodes (pc-NIR LEDs) have important applications in special illumination and spectroscopy analysis. However, the development of efficient NIR-emitting phosphors with high performance is still a challenge. In this work, a chemical unit co-substitution strategy is proposed to realize the excitation transition regulation and successfully achieve high-performance NIR luminescence in Ca 3- y Na y Mg 1- y Sb 2- x Al 2+ y O 12 : x Cr 3+ (0 ≤ x ≤ 0.05, 0 ≤ y ≤ 1) garnet-type solid solution phosphors. Through the excitation transition modulation from the 4 A 2 ground state to the 4 T 1 ( 4 P) and 4 T 1 ( 4 F) excitation state, the excitation intensity at the blue light region is largely enhanced by 25.6 times. Moreover, the NIR-emitting efficiency and thermal stability are improved, with the optimal luminescence internal quantum efficiency of 90.6% and thermal stability of 97%@423 K, without any flux-assisted sintering or reduction atmosphere protection. The structure regulation induced small Stokes shift, weak electron-phonon coupling effect, and decreased non-radiative transition are responsible for the excellent NIR-emitting performance. Finally, the NIR pc-LED is fabricated with photoelectric efficiencies of 18.7%@100 mA and NIR output powers of 63 mW@100 mA, presenting potential applications in nondestructive internal defect detection, veins imaging, and night vision surveillance.
研究领域:
材料科学
·
光学工程
·
固体化学
·
发光材料
·
半导体器件
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Huicai Xie,Quanyi Liu,Xiaohua Luo,Shengcan Ma,Xinqiang Gao,Zhenxing Li,Zhaojun Mo,Jun Shen
For more practical applications, research on magnetic refrigeration has been gradually focused on developing refrigerants with large magnetocaloric effect (MCE) under low magnetic fields (≤2 T). EuTiO 3 exhibits considerable low-field MCE near ordering temperature, meanwhile the magnetic switch from antiferromagnetic to ferromagnetic (AFM-FM) in it provides the feasibility of improving the magnetocaloric performance. In this study, a series of Eu(Ti,Nb,M)O 3 (M=Cu or Zn) compounds were synthesized, and the crystal structure, magnetic properties together with cryogenic MCEs were investigated in detail. The co-substitution contributes to an FM coupling domination in all the compounds. Besides, significantly enhanced and giant low-field MCEs were detected in these compounds. Under the field change of 1 T, all the samples possess remarkable magnetic entropy change (>15 J·kg -1 ·K -1 ) around 5 K without hysteresis. The corresponding refrigerating capacities are calculated to be 68.0, 72.6, 76.0, and 69.6 J·kg -1 , respectively, exhibiting an increase of 149–178% than EuTiO 3 . The outstanding magnetocaloric performances make the Eu(Ti,Nb,M)O 3 (M=Cu or Zn) compounds competitive candidates for cryogenic magnetic refrigeration.
研究领域:
材料科学
·
凝聚态物理
·
功能材料
·
低温工程
·
磁学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）