JOURNAL OF MATERIALS SCIENCE
·
2019
·Vol. 55
·期 3
·990-996
·
IF 3.442
Yin Hang,Zhang Xudong,Lu Jiangwei,Geng Xuemin,Wan Yanfen,Wu Mingzai,Yang Peng
Chemical vapor deposition (CVD)-grown 2D materials like MoS 2 and WS 2 have been widely used for research and application. Here, we study substrates’ effects on CVD-grown MoS 2 and WS 2 . The morphology, crystalline quality and optical properties have been modified while changing substrates, which can be derived from lattice matching between 2D materials and substrate, defect/impurities on the interface and conductance/transparency of different substrates. The results provide suggestion for further study in CVD growth of 2D materials and device fabrications.
研究领域:
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Lei Wang,Ruipeng Hou,Tengfei Huang
The upconversion (UC) emission behavior occurs usually in rare-earth doped compounds but rarely in pure semiconductors. Herein, the UC emission behavior of WO 3 was investigated. The oxygen-vacancy-rich WO 3 nanosheets were rapidly synthesized by high-power laser irradiation. The red UC emission peaked at ∼1.75 eV is observed in the synthesized WO 3 nanosheets under continuous 980 nm or 1940 nm laser excitation. The UC emission stems from the abundant oxygen-deficient levels and belongs to a multiphoton absorption behavior. Meanwhile, the laser-power-dependent UC behavior could be attributed to the transformation of different oxygen defect states. On this basis, a variable output color phosphor based on Er-Yb co-doped WO 3 [WO 3 :(Er, Yb)] was developed. The WO 3 :(Er, Yb) phosphor can change the UC color from green to red with increasing the 980-nm laser power. Moreover, the upconversion behavior of WO 3 can be utilized to assist WS 2 photocatalysis. This work develops a pure semiconductor with an interesting UC emission and clarifies the UC mechanism.
研究领域:
材料科学
·
光学
·
光催化
✓ 已验证
DOI
高影响因子
Materials Today Physics
·
2022
·
IF 11.021
Zilin Ruan,Jianchen Lu,Baijin Li,Qizan Chen,Zhenliang Hao,Lei Gao,Jinming Cai
Structural defects in two-dimensional materials offer an effective way to engineer their functionalities. In-situ local measurements to build the structure-function relationship are crucial for future device technology. Here, we present a comprehensive study of intrinsic defects in single-layer WS 2 grown by chemical vapor deposition using a combination of scanning tunneling microscopy/spectroscopy, non-contact atomic force microscopy and density functional theory calculations. We probed the rarely observed positively charged defects and the intersection of adjacent charging rings at sufficiently high bias caused by subsurface defects. We also directly identified and visualized the widely observed negatively charged defects as chalcogen vacancies-related defects. The results reported here will guide future efforts of targeted defect engineering and doping of the single-layer transition metal dichalcogenides .
研究领域:
材料科学
·
凝聚态物理
·
纳米科技
·
表面科学
·
二维材料
·
半导体物理
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2019
·
IF 4.309
Jiake Li,Weitao Su,Fei Chen,Li Fu,Su Ding,Kaixin Song,Xiwei Huang,Lijie Zhang
Defects play an indispensable role in tuning the optical properties of two-dimensional materials. Herein, we study the influence of defects on the photoluminescence and resonance Raman spectra of as-grown monolayer (1L) WS2. Increasing the density of defects significantly lowers the excitonic binding energy by up to 110 meV. These defect-modified excitonic binding energies in 1L-WS2 strongly mediate the Raman resonance condition, resulting in unexpected Raman intensity variations in the LA(M), 2LA(M), and A1′(Γ) phonon modes. The sample with the highest density of defects exhibits an almost temperature-independent resonance in different Raman modes at low temperature, whereas the samples with low densities of defects exhibit a clear resonance with decreasing temperature. This study will further increase our understanding of the role of defects in resonance Raman spectroscopy and of the phonon–exciton interaction in 1L-WS2.
研究领域:
凝聚态物理
·
材料科学
·
纳米技术
·
光电子学
✓ 已验证
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2015
·Vol. 21
·期 33
·11878-11884
·
IF 5.731
Yongchang Liu,Ning Zhang,Hongyan Kang,Minghui Shang,Lifang Jiao,Jun Chen
We report the synthesis and anode application for sodium-ion batteries (SIBs) of WS 2 nanowires (WS 2 NWs). WS 2 NWs with very thin diameter of ≈25 nm and expanded interlayer spacing of 0.83 nm were prepared by using a facile solvothermal method followed by a heat treatment. The as-prepared WS 2 NWs were evaluated as anode materials of SIBs in two potential windows of 0.01–2.5 V and 0.5–3 V. WS 2 NWs displayed a remarkable capacity (605.3 mA h g −1 at 100 mA g −1 ) but with irreversible conversion reaction in the potential window of 0.01–2.5 V. In comparison, WS 2 NWs showed a reversible intercalation mechanism in the potential window of 0.5–3 V, in which the nanowire-framework is well maintained. In the latter case, the interlayers of WS 2 are gradually expanded and exfoliated during repeated charge–discharge cycling. This not only provides more active sites and open channels for the intercalation of Na + but also facilitates the electronic and ionic diffusion. Therefore, WS 2 NWs exhibited an ultra-long cycle life with high capacity and rate capability in the potential window of 0.5–3 V. This study shows that WS 2 NWs are promising as the anode materials of room-temperature SIBs. Graphical WS 2 nanowires with very thin diameters (≈25 nm) and expanded interlayer spacing (0.83 nm) were synthesized by using a facile solvothermal method followed by heat treatment. This distinctive nanostructure exhibits an ultra-long cycle life with high capacity and rate capability as anode material of sodium-ion batteries (see figure).
研究领域:
材料科学
·
储能
·
纳米技术
·
电化学
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry C
·
2020
·
IF 4.189
Yi Yao,Fei Chen,Li Fu,Su Ding,Shichao Zhao,Qi Zhang,Weitao Su,Xin Ding,Kaixin Song
Probing the nanoscale localized optoelectronic properties induced by defects in two-dimensional (2D) transition-metal dichalcogenides challenges the spatial resolution and functionalities of many analytic tools. Herein, tip-enhanced photoluminescence (TEPL) combined with in situ photosensitive Kelvin probe force microscopy was used to fulfill such demand by exemplifying highly defective monolayer WS2 (1L-WS2) prepared by chemical vapor deposition. The contact potential difference (CPD) results indicate weak variation of work function without light but strong fluctuation of surface photovoltage (SPV) depending on the excitation laser wavelength and power. TEPL measurements reveal that the PL intensities of neutral exciton (A0) and trion (A–) vary quickly in the scale of a few hundreds of nanometers, which can be closely correlated to the distribution of SPVs. The CPD and TEPL results indicate the important role of defects in mediating the optoelectronic behaviors of 1L-WS2 in the nanoscale. The obtained results would further improve the understanding of the localized optoelectronic properties of intrinsic defects in 2D materials.
研究领域:
纳米技术
·
材料科学
·
光电子学
·
凝聚态物理
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2020
·
IF 7.1
Yan Chen,Yunlei Zhou,Hanwen Wu,Lingsong Wang,Runze Guo,Huanshun Yin,Jun Wang,Shiyun Ai
Histone acetylation is crucial transcription-activating modification, which is achieved by histone acetyltransferase using acetyl coenzyme A as acetyl donor. As by-product, the concentration of coenzyme A (CoA) is related to histone acetyltransferase. Based on it, a newly and sensitively photoelectrochemical method was designed for histone acetyltransferase detection, where WS 2 nanosheets were employed as photoactive material, polydopamine (PDA) was used as solid-state electron donor, SMCC was adopted as crosslinker for capture CoA through the covalent reaction between SMCC and –SH of CoA, and streptavidin was used as signal inhibition unit. This novel PEC strategy presented a superior linear relationship with the range of 0.1–200 nM. The detection limit was 47 pM (S/N = 3). This assay was further applied to investigate the effect of heavy metal and anacardic acid on the effect of histone acetyltransferase activity, provided a platform for the screening of histone acetyltransferase inhibitor, and assessing the applicability of this method in ecotoxicological effect evaluation.
研究领域:
生物化学
·
分析化学
·
分子生物学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2018
·
IF 4.229
Yaqi Jing,Xiaoyu Mu,Chengwang Xie,Haile Liu,Ruijuan Yan,Haitao Dai,Changlong Liu,Xiao-Dong Zhang
Transition metal dichalcogenides (TMDs) have attracted significant research interest due to its promising performance in hydrogen evolution reaction (HER). Synergistic effect between materials interface can improve the electrocatalytic properties . In this work, the WS 2 –CoS 2 heterostructure supported on carbon paper (CP) was elaborately fabricated by a three-step method. Owing to the synergistic effect, WS 2 –CoS 2 heterostructure exhibits an excellent electrocatalytic activity with a low overpotential of 245 mV at 100 mA/cm 2 and a small Tafel slope of 270 mV/dec toward HER. We demonstrate that the increased specific surface area and conductivity of the heterostructure play a key role in enhancing the overall catalytic efficiency. Moreover, the crystal lattice distortion in the heterostructure could induce charge redistribution and improve electron transfer efficiency, which may also benefit the whole HER activity.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2016
·
IF 3.014
Hechun Lin,Jingwei Wang,Qianqian Luo,Hui Peng,Chunhua Luo,Ruijuan Qi,Rong Huang,Jadranka Travas-Sejdic,Chun-Gang Duan
An efficient nitrate/HCl chemical exfoliation system for rapid production of MoS 2 and WS 2 nanosheets were presented here. After exfoliation in the NaNO 3 /HCl solution with the assistant of ultrasonication, MoS 2 and WS 2 nanosheets were produced with yields of 58% and 52%, respectively. The morphologies and crystallinity of MoS 2 and WS 2 nanosheets were characterized by transmission electron microscopy , atomic force microscopy and X-ray diffraction spectroscopy. This efficient exfoliation method is based on the synergy effects of surface etching, insertion of ions and eruption of gas bubbles. The MoS 2 and WS 2 nanosheets exhibited improved catalytic activity toward the oxygen-reduction reaction.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2020
·
IF 7.888
Yaping Pan,Fawei Zheng,Xixi Wang,Hongye Qin,Enzuo Liu,Junwei Sha,Naiqin Zhao,Ping Zhang,Liying Ma
Hydrogen evolution reaction (HER) activities of WS 2 can be improved by doping exotic atom to increase active sites on base plane and narrow the bandgap. However, most of these catalysts of exotic atom doped WS 2 are composed of semiconductor and the electronegativity between atoms is similar, which do harm to tuning bandgap with a wide range and decreasing the value of free Gibbs energy (Δ G H ) for hydrogen adsorption. Given that Te can tune bandgap with a wide range and the electronegativity between S and Te differ greatly, a vertically arranged WS 2 nanoelectrode is prepared by doping Te on WS 2 . According to experimental studies and the density functional theory calculations (DFT), the bandgap of WS 2 nanosheets is successfully narrowed after doping Te. This lowers the Schottky barrier which benefits the transfer of charges and improves electrocatalytic performance in turn. Meanwhile, the presence of Te atoms with much lower electronegativity than S increases the electron density of the adjacent region, thereby the S edges of basal plane around Te atoms and hollow sites of WS 2 nanosheet become active to drive HER, which has been verified by the reduced Δ G H of S edges of basal plane from 2.27 to 2.08 eV and hollow sites from 2.28 to 1.85 eV after the doping in DFT. Te-doped WS 2 nanosheets used as excellent HER catalysts with an overpotential of 213 mV to drive a current density of 10 mA/cm 2 , a small Tafel slope of 94 mV/dec, along with a superior stability in acid media.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Advanced Electronic Materials
·
2024
·
IF 5.3
Zi-hao Dong,Qi-hang Zhang,Kai Liu,Shao-jie Fu,Xu-Hao Hong,Qian-jin Wang,Yan-qing Lu,Yong-yuan Zhu,Xue-jin Zhang
Two-dimensional (2D) materials are widely used in various optical, electronic, and optoelectronic devices. However, the realization of visible light emission and near-infrared photodetection functions in a single device remains a challenge. Here, an integrated dual-functional device is developed by manipulating the excitons of WS 2 within a graphene/hBN/WS 2 /graphene heterostructure. When operating as a photodetector at low external bias, the dark current is well suppressed by the hBN layer. With the excellent two-photon absorption (TPA) property of monolayer WS 2 , the photoresponse range of the photodetector can be extended to the near-infrared region, achieving a responsivity of up to 0.19 mA/W at 1145 nm. At high external bias, the device can work in light-emitting mode, in which the electroluminescence (EL) wavelength can be tuned via gate voltage. This atomically thin device opens up possibilities for applications in miniaturized display, sensing, and monitoring systems.
研究领域:
材料科学
·
光电子学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Yiding Li,Qiang Zhang,Simin Shen,Siqi Wang,Liangliang Shi,Dequan Liu,Yujun Fu,Deyan He
Effectively limiting the shuttle effect is the key to improving the electrochemical performance of Li-S batteries. Here, the synthesis of WO 3 -WS 2 heterostructures is reported by electrospinning and in situ sulfurization strategies, combining the initial WO 3 nanoparticles with the sulfurization product WS 2 . It was found that the obtained bifunctional heterostructures enhance the electrolyte wettability, optimize intermediate regulation performance, accelerate Li + /e − diffusion, and thus exhibit excellent electrochemical characteristics in Li-S batteries. Through experiments and density functional theory (DFT) calculations, the WO 3 -WS 2 heterostructures were considered as a coupled creative solution with multiple advantages. Different from the batteries using single-component or single-configuration catalyst, the prepared Li-S batteries with the WO 3 -WS 2 heterostructures exhibited synergistic enhanced electrochemical performance and high-temperature crushing resistance. Even under severe conditions, including high sulfur loading (10.3 mg cm −2 ), lean electrolyte (5.8 μL mg −1 ), high current density (7.0 A g −1 ), extended cycling (1600 cycles), and high temperature (90 °C), the representative battery exhibited stable cycling performance.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）