APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Xingchao Zhang,Ruoyu Zhang,Siying Niu,Jiming Zheng,Chongfeng Guo
The MoS 2 /g-C 3 N 4 heterojunction composite (marked as MoS 2 /g-C 3 N 4 -H) was successfully prepared via calcining the melamine coated MoS 2 nano-sphere, where the thin g-C 3 N 4 nano-sheets were tightly grown on the surface of MoS 2 nano-sphere to form MoS 2 inlaying in g-C 3 N 4 heterostructure. The detailed charge transfer mechanism was discussed by combining theoretical calculation and experiments, in which the intrinsic cause of photo-generated charge separation and transfer was determined as the directional built-in electric field driven by different Fermi levels of MoS 2 and g-C 3 N 4 . Comparatively, the enhanced photo-catalytic performance and stability of the sample were assessed by degrading the Rhodamine (RhB) and reducing the Dichromate (Cr 6+ ) solutions under the irradiation of the simulated sunlight, which could be attributed to the widened spectral absorption range and improved electron-hole separation rate. Based on above results, the photo-catalytic mechanism involving redox reactions was also clearly proposed.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL
·
2016
·
IF 3.958
Lei Zhao,Baoyue Zhang,Xin Xiao,Feng Long Gu,Rui-Qin Zhang
Active species such as holes, electrons, hydroxyl radicals ( OH), and superoxide radical anions ( O 2 − ) involved in the photocatalytic oxidation of benzyl alcohol (BA) into benzaldehyde (BAD) on TiO 2 under ultraviolet (UV) light were investigated by adding corresponding scavengers. The experimental results show that the oxidation of BA into BAD is driven mainly by the holes and OH radical. The role of dissolved O 2 was studied by bubbling N 2 through the reaction. The results show that the dissolved O 2 is, to some extent, the source of OH. Additional density functional theory (DFT) calculations identified two H-abstraction pathways ( R abs OH and R abs α). The structure of the R abs OH product is less stable and tends to transfer resulting in the R abs α product. The holes are the main driving force for the abstracting of H from BA. The OH radical combines with the H-abstract product to form a precursor of product BAD, detected by LC–MS technique ( m / z 123), which then undergoes an intramolecular dehydration reaction to form BAD. The results will help to select the optimal active species for the photocatalytic oxidation of BA into BAD on TiO 2 under UV light.
研究领域:
物理化学
·
光催化
·
环境化学
·
材料化学
·
理论计算化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2018
·
IF 4.439
Jishu Han,Fangxu Dai,Ying Liu,Ruiyang Zhao,Lei Wang,Shouhua Feng
The photocatalytic hydrogen production has become one of the most promising strategies to solve the energy crisis and environmental pollution. Novel CdSe/SrTiO 3 nanocomposites (average diameter ≈ 114.6 nm) with high photocatalytic activity are synthesized and used for visible light photocatalytic water splitting for hydrogen production . Through optimizing the concentration of CdSe QDs, CdSe/SrTiO 3 nanocomposites exhibit increased visible light absorption and enhanced photocatalytic hydrogen evolution efficiency compared to SrTiO 3 nanoparticles. The maximum H 2 evolution amount reaches to 3350.53 μmol in 8 h by using CdSe/SrTiO 3 -3 as catalyst. Owing to the formation of heterojunction at the interface between CdSe and SrTiO 3 , the electrochemical impedance spectrum of CdSe/SrTiO 3 -3 exhibits the smallest arc radius and the photocurrent density of CdSe/SrTiO 3 -3 reaches to 0.26 μA cm −2 . The photogenerated electrons are effectively separated and transferred and the recombination of electron-hole pairs is avoided, thus significantly improving the photocatalytic hydrogen production performance of CdSe/SrTiO 3 nanocomposites.
研究领域:
材料科学
·
物理化学
·
纳米催化
·
能源材料
·
光催化
✓ 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
·
半导体器件
·
表面工程
·
能源材料
✓ 已验证
DOI
高影响因子
ORGANIC ELECTRONICS
·
2019
·
IF 3.495
Yan Zhang,Zhenlong Zhang,Yanyan Liu,Yuefeng Liu,Huiping Gao,Yanli Mao
In this work, we synthesized CuInSe 2 quantum dots (CISe QDs) and applied them to perovskite solar cells (PSCs) as an inorganic hole-transporting material (HTM). A power conversion efficiency (PCE) of 12.8% was achieved for the PSCs using CISe QDs as the HTM, which is the highest value reported to date for devices with a Cu-based chalcopyrite semiconductor as HTM. More importantly, the stability of PSCs with CISe QDs was significantly improved compared with that of the devices using spiro-OMeTAD as the HTM. These results demonstrate that CISe QDs are a promising inorganic HTM for PSCs with long-term stability and low cost.
研究领域:
材料科学
·
光伏技术
·
纳米材料
·
能源化学
·
半导体物理
✓ 已验证
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 59
·34658-34670
·
IF 3.049
Xiangyu Wang,Yu Xie,Jun Ma,Ping Ning
The two-stage removal process of tetracycline (TC) in aqueous solutions using a novel photocatalyst based on nano-zero-valent iron (NZVI), g-C3N4 and expanded graphite by carbon layer (EGC) is reported for the first time. The composite (NZVI/g-C3N4@EGC) exhibits remarkable adsorption, reduction ability and visible light activity over the reaction course. Compared with pristine g-C3N4 (25.9%) and pure NZVI (45.9%), NZVI/g-C3N4@EGC achieves high degradation efficiency of TC (98.5%) due to the formation of a heterogeneous photo-Fenton system. This study shows that synergistic effects are achieved in the reaction system, including maintaining the reduction ability of NZVI and enhancing the photocatalytic activity of g-C3N4 by facilitating the separation of photogenerated electrons (e−) and holes (h+). TC removal involved a two-stage process of adsorption–reduction and photo-degradation. The quencher experiments determined that holes (h+) and superoxide radicals (˙O2−) are the major reactive species in the degradation of TC. The degradation pathways of TC were proposed based on the analysis of the intermediates. In addition, NZVI/g-C3N4@EGC revealed a high stability in a five-cycle test and good magnetic properties for facile separation from aqueous solutions. From an application viewpoint, NZVI/g-C3N4@EGC has favorable prospects in the direction of the photocatalytic degradation of antibiotic wastewater.
研究领域:
环境化学
·
材料科学
·
光催化
·
水污染治理
·
纳米复合材料
·
抗生素降解
✓ 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 POWER SOURCES
·
2017
·
IF 6.395
Zhiliang Chen,Guang Yang,Xiaolu Zheng,Hongwei Lei,Cong Chen,Junjie Ma,Hao Wang,Guojia Fang
Perovskite solar cells have developed rapidly in recent years as the third generation solar cells. In spite of the great improvement achieved, there still exist some issues such as undesired hysteresis and indispensable high temperature process. In this work, bulk heterojunction perovskite-phenyl-C 61 -butyric acid methyl ester solar cells have been prepared to diminish hysteresis using a facile two step spin-coating method. Furthermore, high quality tin oxide films are fabricated using pulse laser deposition technique at room temperature without any annealing procedure. The as fabricated tin oxide film is successfully applied in bulk heterojunction perovskite solar cells as a hole blocking layer. Bulk heterojunction devices based on room temperature tin oxide exhibit almost hysteresis-free characteristics with power conversion efficiency of 17.29% and 14.0% on rigid and flexible substrates , respectively.
研究领域:
材料科学
·
光伏技术
·
纳米材料
·
能源材料
·
半导体器件
·
薄膜制备
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2019
·
IF 2.961
Run Wang,Yue Zhang,Fu-Xing Yu,Yajie Dong,Ya-Lan Jia,Xing-Juan Ma,Qiang Xu,Yanhong Deng,Zu-Hong Xiong,Chun-Hong Gao
An efficient perovkite light-emitting diode (PeLED) is fabricated by incorporating 1,3,5-tri (m-pyrid-3-yl-phenyl)benzene (TmPyPB) between the emitting layer (EML) and the electron transporting layer (ETL), where TmPyPB plays an indispensable blocking effect on both excitons and holes. It shows a maximum current efficiency of 9.37 cd/A, and the corresponding external quantum efficiency (EQE) of 2.42% with a saturated green color Commission International de I'Eclairage (CIE1993) coordinated of (0.1279, 0.7951) under a driving voltage of 6 V. Meanwhile, the operational lifetime of the TmPyPB-based PeLED is improved to about 2.6-fold to that of the one with only the traditional ETL of aluminum 8-hydroxyquinolinate (Alq 3 ). The enhancements of electroluminescence (EL) performance are mainly attributed to better confinement of both the holes and the excitons in the EML, and more balanced carrier transportation in the TmPyPB-based PeLED. This work offers a feasible strategy to develop high performance optoelectronic devices.
研究领域:
材料科学
·
光电子学
·
纳米技术
·
半导体器件
·
功能材料
✓ 已验证
DOI
高影响因子
EcoMat
·
2021
·Vol. 3
·期 5
·e12134
·
IF 0
Weixia Lan,Jialu Gu,Shiwei Wu,Yan Peng,Min Zhao,Yingjie Liao,Tao Xu,Bin Wei,Liming Ding,Furong Zhu
Improved efficiency and stability of the organic solar cells (OSCs) are the critical considerations for practical applications. The interface between the interlayer and bulk heterojunction has recently been shown as one of the weak links associated with the degradation in the nonfullerene acceptor (NFA)-based OSCs. It shows that the removal of the interfacial chemical reactions between the 2-(3-oxo-2,3-dihydroinden-1-ylidene)malononitrile (INCN) moieties in NFA and poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS) hole extraction layer (HEL) is desired for enhancing the device stability. In this work, we show that the use of a bilayer MoO 3 /antimonene HEL favors the operational stability in OSCs through maintaining a high built-in potential and suppression of an undesired interfacial reaction between INCN moieties in NFA and the PEDOT structures in PEDOT:PSS. A power conversion efficiency of 16.68% is also obtained for the OSCs with a bilayer MoO 3 /antimonene HEL, prepared using a blend system of PM6:Y6, demonstrating its suitability for high-performance OSCs.
研究领域:
材料科学
·
光伏技术
·
纳米材料
·
表面化学
·
器件物理
✓ 已验证
DOI
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2016
·Vol. 18
·期 48
·32903-32909
·
IF 4.449
Fan Zhang,Jun Song,Ming Chen,Junchen Liu,Yuying Hao,Yuncai Wang,Junle Qu,Pengju Zeng
Organic–inorganic metal halide perovskites have led to remarkable advancements in emerging photovoltaics. The rapid increase in the power conversion efficiency (PCE) of PSCs has been mainly achieved by improving perovskite morphology and crystallinity. Herein, we report a simple and effective means to improve perovskite grain sizes using a porous hole transport layer (i.e., PEDOT:PSS in this work). We used polystyrene nanospheres as a sacrificial template to fabricate the porous-PEDOT:PSS. The growth of the CH3NH3PbI3 perovskite film on the porous-PEDOT:PSS substrate yields a dramatic improvement in crystallinity and an enhancement in perovskite grain sizes. When the porous structure was applied as a hole transport layer in PSCs with planar heterojunction structures, the efficiency was significantly enhanced from 15.33% for the planar device to 17.32%. This simple method for enhancing perovskite morphology and crystallinity paves the way for its application to other device architectures for enhanced photovoltaic performance.
研究领域:
材料科学
·
光伏技术
·
纳米结构调控
·
能源材料
·
薄膜制备
✓ 已验证
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2020
·Vol. 22
·期 23
·13214-13222
·
IF 3.43
Yongfang Yuan,Xiaowen Zhang,Dongliang Li,Xiuyun Zhang,Lihui Wang,Zongliu Lu,Liming Liu,Feng Chi
Hole injection governs the efficiency of ultraviolet organic light-emitting diodes (UV OLEDs) due to the deep highest occupied molecular orbital level of the emissive molecule. Tungsten oxides (WOx), transition metal oxides with high work functions and good stability, cast light on solving this problem. By a low-cost, scalable and high-throughput manufacturing process, herein the facile synthesis of a WOx solution and its doping in poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS + WOx) is systematically investigated for assembling efficient UV OLEDs. X-ray diffraction, atomic force microscopy, scanning electron microscopy and X-ray photoelectron spectroscopy measurements confirm that WOx and PEDOT:PSS + WOx have good film morphology and exceptional electronic properties, such as the oxygen deficiency dominated non-stoichiometry of WOx. With PEDOT:PSS + WOx tailoring hole injection and 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole as the emitter, the UV OLEDs show outstanding electro-optic performance, with a radiance of 3.98 mW cm−2, external quantum efficiency of 2.30%, electroluminescence peak at 400 nm and full width at half maximum of 47 nm, which is superior to the performance of the corresponding reference materials. The mechanism of charge transfer from the PEDOT polycation to WOx, enhancing conductivity, is responsible for the robust hole injection/transport and is further elucidated by ultraviolet photoelectron spectroscopy and impedance spectroscopy, contributing to the optimization of the carrier balance and recombination zone. Our results illustrate an alternative approach for boosting UV OLED performance and advancing organic electronics.
研究领域:
材料科学
·
有机电子学
·
薄膜器件
·
光电功能材料
·
半导体器件物理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）