Journal of Materials Chemistry A
·
2014
·Vol. 2
·期 37
·15546-15552
·
IF 0
Yitan Li,Lin Wei,Cuncun Wu,Chang Liu,Yanxue Chen,Hong Liu,Jun Jiao,Liangmo Mei
Uniform zinc oxide (ZnO) nanosheet arrays were grown on woven titanium wires using a low temperature hydrothermal method. Photoanodes were prepared by depositing CdS and CdSe quantum dots onto the ZnO nanosheet arrays by a successive ionic layer adsorption and reaction (SILAR) method. Solar cells were assembled using these nanostructured photoanodes and their photovoltaic performance was characterized. The effect of using SILAR cycles for the deposition of quantum dots on the performance of these nanostructured solar cells was investigated systematically. The overall light-to-electricity conversion efficiency of 0.98% was achieved under 100 mW cm−2 illumination for flexible CdS/CdSe co-sensitized solar cells using conventional Pt foils as counter electrodes. To further improve the performance of the flexible solar cells, PbS and Cu2S counter electrodes based on Pb and Cu foils were fabricated. The best conversion efficiencies of flexible CdS/CdSe co-sensitized solar cells using Cu2S and PbS counter electrodes were 3.4% and 2.5%, which demonstrated a significant enhancement in values for short circuit current, open circuit voltage, and fill factor compared to those obtained with the commonly used Pt and Au electrodes.
研究领域:
材料科学
·
纳米科技
·
能源材料
·
光电化学
·
半导体器件
✓ 已验证
DOI
International Journal of Electrochemical Science
·
2023
·Vol. 12
·期 5
·4610-4618
·
IF 1.5
Chenle Zhang,Libo Deng,Peixin Zhang,Xiangzhong Ren,Yongliang Li,Tingshu He
Electrocatalytic NiS 2 cubes were directly synthesized on F-doped tin oxide using a hydrothermal approach and used as counter electrode in dye-sensitized solar cells (DSSCs). The NiS 2 cubes displayed an excellent electrocatalytic activity in the reduction of I 3 − showing a power conversion efficiency of 5.56%, which is close to that of the Pt-containing DSSC (7.05%). Furthermore, the NiS 2 cubes showed a comparable stability to Pt. This is ascribed to the low resistance to diffusion and transfer of electrolyte ions. These results suggest that the NiS 2 cubes prepared through a facile process is a promising substitute to Pt electrode.
研究领域:
材料科学
·
能源化学
·
纳米材料
·
电化学
·
光伏器件
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Hui Chen,Jinfeng Wang,Chenchen Jia,Junpeng Mou,Lei Zhu
For the purpose of increasing the power conversion efficiency (PCE) meanwhile decreasing the cost of dye-sensitized solar cell (DSSC), Cu 2 ZnSnS 4 - multiwall carbon nanotubes (CZTS-MWCNTs) nanohybrid Pt-free counter electrode (CE) was prepared via a facile fabricating route. In brief, CZTS nanoparticles were synthesized by a solvothermal method and the composite film was fabricated by spin coating the aqueous solution of the composite. The short-circuit current density and PCE of the DSSC with CZTS-MWCNTs CE were found to be 16.62 mA cm −2 and 9.04%, respectively. But the corresponding values were 15.42 mA cm −2 and 8.74% for a DSSC with a pure Pt-CE. This is owing to the synergistic effect of the intrinsic superior electrocatalytic activity of the CZTS nanoparticles and highly specific surface area and high electrical conductivity of the MWCNTs . The presence and distribution of CZTS-MWCNTs on the CE were characterized by X-Ray Diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM), respectively. Cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) were examined for confirming the high electrocatalytic efficiency of this nanohybrid system.
研究领域:
材料科学
·
能源化学
·
纳米技术
·
电化学
·
光伏器件
✓ 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
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发光材料
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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
CERAMICS INTERNATIONAL
·
2014
·Vol. 40
·期 9
·15199-15206
·
IF 2.086
Yanbo Yang,Xiao Peng,Si Chen,Liping Lin,Bao Zhang,Yaqing Feng
The novel hierarchical compact layer involving ZnO and TiO 2 blocking films is used to improve the overall performance of dye-sensitized solar cells. The ZnO compact films are fabricated as a bottom layer to block the electrons injection to the conductive glass and improve the open-circuit voltage. The TiO 2 compact layer is employed to suppress back electron transfer and avoid ZnO contacting the acid dyes directly. The short-circuit current density of the DSSC containing the hierarchical compact layer is improved by 30% compared to that of one with only ZnO as the compact layer. The open-circuit voltage is increased by 4% after introducing the additional TiO 2 blocking layer between the ZnO compact layer and mesoporous TiO 2 layer. Overall, the short-circuit current density, open-circuit voltage and solar energy conversion efficiency are enhanced by 15.3%, 3.7% and 29.6%, respectively, relative to the traditional DSSC without any blocking layers. The ZnO–TiO 2 blocking layer has been characterized by electrochemical impedance spectroscopy , open-circuit voltage decay and dark current measurement to reveal the mechanism of short-circuit current density and open-circuit voltage improvement.
研究领域:
材料科学
·
纳米科技
·
能源化学
·
光伏技术
·
表面科学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2019
·Vol. 45
·期 12
·15589-15595
·
IF 3.45
Sining Yun,Yuzhi Hou,Chen Wang,Yangliang Zhang,Xiao Zhou
Mo-based binary/ternary nanocomposites were designed and prepared via soft template synthesis by combining Mo 2 C and Bi/Mo 2 C into mesoporous carbon (MC). The materials were characterized by using various analytical and electrochemical techniques . When Mo 2 C/MC composites were used as counter electrodes (CEs) in iodide-mediated dye-sensitized solar cells (DSSCs), the power conversion efficiencies (PCEs) of the cells reached 7.29%, and the performance of DSSC with Bi/Mo 2 C/MC was 8.06%, which was much higher than that of the cell with Pt CE (7.08%). The excellent electrochemical stability of Mo-based nanocomposites in triiodide/iodide electrolyte indicated that they could be promising alternatives to Pt electrodes in DSSCs. This work provided a new idea for the development of metal/carbide/carbon nanocomposite CE materials for DSSCs.
研究领域:
材料科学
·
能源化学
·
电化学
·
纳米科技
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2015
·
IF 2.288
J.L. Wang,E.H. Song,M. Wu,W.B. Dai,S. Ye,Q.Y. Zhang
Selectively enhanced green upconversion (UC) and near-infrared (NIR) downconversion (DC) emissions of Er 3+ by Yb 3+ -Mn 2+ dimer sensitizing have been demonstrated in Er 3+ /Yb 3+ /Mn 2+ tri-doped spinel MgGa 2 O 4 upon excitation of 980 nm laser diode (LD). By optimizing the doping rate of Mn 2+ , the intensity ratio of green to red UC emission intensities of Er 3+ (G/R) could be enhanced about 10 times. Meanwhile, the 1.5 μm NIR DC emission could also be increased about 3.6 times in this system. The DC and UC emission properties, UC mechanism, as well as the enhancing mechanism have been investigated and discussed in detail. A selectively enhancing mechanism based on Yb 3+ -Mn 2+ dimer sensitizing is proposed to explain the selectively enhancing phenomena. This work could inspire the design of novel UC materials for various applications, such as temperature sensors and optical transmission, etc.
研究领域:
光学材料
·
生物医学光子学
·
无机功能材料
·
分子影像
·
转化医学
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2017
·Vol. 27
·期 2
·413-418
·
IF 2.594
Yanyun Zhang,Xichuan Yang,Weihan Wang,Xiuna Wang,Licheng Sun
X1 (MeO-TPD) is an inexpensive and easily synthesized π -conjugated molecule that has been used as a hole-transport material (HTM) in solid-state dye-sensitized solar cells (ssDSSCs), achieving relatively high efficiency. In this paper, we characterize the physicochemical properties of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) and show that it is a promising p-dopant in a spin-coating solution with X1 as the HTM. The doped ssDSSCs showed an increase in short-circuit current density from 5.38 mA cm –2 to 7.39 mA cm –2 , and their overall power conversion efficiency increased from 2.9% to 4.3%. Also, ssDSSCs with DDQ-doped X1 were more stable than the undoped samples, demonstrating that DDQ can act as a p-type dopant in X1 as an HTM for highly efficient, stable ssDSSCs.
研究领域:
材料科学
·
能源化学
·
光伏技术
·
纳米材料
·
半导体器件
·
表面化学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2022
·
IF 4.171
Yunkang Bu,Yu Chen,Xingyue Chen,Yichun Zhang,Degang Deng,Yuyu Shen,Liuyan Zhou,Chenwei Xu
Up conversion luminescent materials Sr 2 YTaO 6 : Er 3+ , Yb 3+ phosphors were prepared by high temperature calcination . In view of the formation, temperature characteristics , and photoluminescence features of the sample, X-ray diffraction and photoluminescence were used. Under the excitation at 980 nm, the series of samples is significantly stimulated by Er 3+ up-conversion luminescence and Yb 3+ sensitization at 524, 550 and 659 nm. According to the diversity of temperature sensing performance from these three highest peaks, a dual-mode temperature sensor on account of fluorescence intensity ratio (thermally coupled level between 2 H 11/2 and 4 S 3/2 , and nonthermally coupled energy levels between 2 H 11/2 and 4 F 9/2 ) is achieved by using a single luminescent center. Moreover, the phosphor has strong thermal stability, which is helpful to improve the accuracy of temperature measurement. Under the temperature measurement of a dual-mode temperature sensor, it is calculated that the optimal absolute sensitivity S a of thermally coupled energy level is 0.78 × 10 −3 K −1 (473 K) and relative sensitivity S r is 1.32 %K −1 (293 K), and the maximum optimal absolute sensitivity S a of non-thermally coupled energy level is 1.02 × 10 −4 K −1 (473 K) and relative sensitivity S r is 0.58 %K −1 (293 K). All results imply that Sr 2 YTaO 6 : Er 3+ , Yb 3+ phosphors are promising materials for self-referenced optical temperature measurement.
研究领域:
材料科学
·
光学工程
·
无机化学
·
功能材料
·
生物医学传感
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2019
·
IF 2.961
Hao Lin,Dekang Xu,Yongjin Li,Lu Yao,Liqin Xu,Ying Ma,Shenghong Yang,Yueli Zhang
Lanthanide-doped upconversion (UC) materials are commonly excited by 700–1000 nm laser because of Yb 3+ (980 nm excitation) and Nd 3+ (808 nm excitation) are typically used as sensitizers. However, the excitation band located in the second near-infrared window (NIR-II, 1000–1700 nm) demonstrates the deeper penetration in biological tissue with minimum tissue scattering and autofluorescence. Herein, intense red UC emission in Er 3+ -sensitized NaLuF 4 particles under 1532 nm NIR-II excitation is presented. Red UC luminescence is significantly enhanced and purified through confining the 1532 nm excitation energy by Ho 3+ and Tm 3+ mediators, via an energy back transfer pathway (Er 3+ → Ho 3+ → Er 3+ and Er 3+ → Tm 3+ → Er 3+ ). Furthermore, when the particles injected into the fresh beef, red UC luminescence can be distinctly observed from the inside of beef under 1532 nm NIR-II excitation, implying the deep penetration of 1532 nm NIR-II excitation and 660 nm red UC emission. Our results suggest that bright red UC luminescence from Er 3+ -sensitized NaLuF 4 crystals with 1532 nm NIR-II excitation may be suitable for deep optical imaging .
研究领域:
材料科学
·
生物医学工程
·
光学成像
·
纳米医学
·
分子影像
✓ 已验证
DOI
高影响因子
JOURNAL OF NON-CRYSTALLINE SOLIDS
·
2014
·
IF 1.716
J. Yuan,W.C. Wang,D.D. Chen,M.Y. Peng,Q.Y. Zhang,Z.H. Jiang
Enhanced 1.8 μm emission from Tm 3+ by Yb 3+ sensitization and bubbling in tungsten tellurite glasses has been demonstrated under the excitation of a 976 nm laser diode . Radiative properties such as spontaneous emission probabilities, radiative lifetimes and fluorescence branching ratios along with absorption and emission cross sections have been calculated from the absorption spectra . The influences of Yb 3+ concentration, Tm 3+ concentration, and bubbling time on spectroscopic properties have been thoroughly investigated. It is found that with increasing the bubbling time to 35 min, OH − content deceases sharply while 1.8 μm emission intensity improves greatly and 3 F 4 level lifetime prolongs to 1.57 ms close to radiative time. After 35 min, they change very little due to almost reaching the dynamic balance. The strength of interaction between Tm 3+ and OH − is determined. The energy transfer mechanism between Yb 3+ and Tm 3+ is proposed by photoemission spectroscopy and lifetime measurement. The energy transfer coefficients have been analyzed by the extended spectral overlap method and hopping model. Large ratio of the forward energy transfer from Yb 3+ to Tm 3+ to the backward one (223) and high energy transfer efficiency (97%) from Yb 3+ to Tm 3+ ensure efficient 1.8 μm emission. Hence, Yb 3+ sensitization and the reduction of OH − content could be expected to open up a possibility to achieve high efficient 2.0 μm lasing from Tm 3+ under a 976 nm LD pump.
研究领域:
光学材料
·
激光物理
·
固体激光器
·
光谱学
·
无机非金属材料
·
光子学
·
稀土发光材料
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2017
·
IF 3.133
Jianguang Jia,Chunmei Liu,Yuan Lin,Xiaowen Zhou
Charge recombination is an important factor that limits the cell efficiency of quantum dot sensitized solar cells (QDSSCs). Herein, we report a facile way to improve the cell performance of CdSe sensitized ZnO QDSSC by overcoating a thin layer of ZnSe on CdSe/ZnO film through a successive ionic layer adsorption and reaction (SILAR) procedure. Photovoltaic investigations indicate that ZnSe overcoating can increase photocurrent and photovoltage of the cell, resulting in significant enhancement of the cell efficiency, which is much better than the widely used traditional ZnS material. The superior role of ZnSe overcoating is ascribed to its large inhibition of charge recombination loss owing to its suitable band structure, efficient passivation of ZnO and CdSe QDs as well as its small lattice mismatch with CdSe that leads to the large decrease of surface/interface defects in CdSe/ZnO photoanode . This finding provides an alternative efficient way to enhance the cell performance of ZnO based QDSSC by suppressing the charge recombination.
研究领域:
材料科学
·
纳米科技
·
能源化学
·
半导体物理
·
光伏技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）