Materials Horizons
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2019
·Vol. 6
·期 7
·1416-1424
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IF 14.356
Yuanqing Xu,Shulin Chen,Zhipeng Dou,Yanhong Ma,Yang Mi,Wenna Du,Yin Liu,Jianqi Zhang,Jinquan Chang,Cheng Liang,Jin Zhou,Hongbo Guo,Peng Gao,Xinfeng Liu,Yanke Che,Yong Zhang
The production of two-dimensional quantum sheets (2D QSs) from bulk layered materials is highly desired but far from satisfactory. Herein, we report a unified top-down method capable of producing a range of 2D QSs in high yields. The method combines silica-assisted ball-milling and sonication-assisted solvent exfoliation and thus enables production of graphene QSs (GQSs), boron nitride QSs (BNQSs), molybdenum disulfide QSs (MoS2 QSs), and tungsten disulfide QSs (WS2 QSs) in exceedingly high yields of 35.5, 33.6, 30.2, and 28.2 wt%, respectively. The as-produced 2D QSs are confirmed as intrinsic and defect-free by multiple characterization techniques. Such 2D QSs can be collected as powders and then redispersed in a wide range of solvents with high concentration up to 5 mg mL−1. Both (re)dispersions and solid thin films of the 2D QSs exhibit extraordinarily high performance in linear and nonlinear optics. Specifically, the QS (re)dispersions show prominent exciton-, solvent-, and concentration-dependent photoluminescence, while the QS solid thin films demonstrate exciting solid-state fluorescence (with lifetimes up to 3.0 ns) and remarkable nonlinear absorption saturation (with absolute modulation depths up to 59% and saturation intensities down to 6.70 kW cm−2 (0.67 nJ cm−2)). Our method could be applicable to any bulk layered materials and therefore paves the way for mass production and full exploration of 2D QSs.
研究领域:
材料科学
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纳米技术
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光学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2019
·Vol. 8
·期 5
·1796-1802
·
IF 6.641
Zhiyuan Wang,Long Gao,Xiaozhen Wei,Min Zhao,Yanqin Miao,Xuefeng Zhang,Haixia Zhang,Hua Wang,Yuying Hao,Bingshe Xu,Junjie Guo
Efficient hole injection layers (HILs) are crucial for organic light emitting diodes (OLEDs) to achieve high performance. In this work, we report that doping PEDOT:PSS with semi-conductive antimonene quantum sheets (AMQSs) can effectively adjust the work function from −5.2 eV to −4.9 eV, and it exhibits a significantly higher hole injection performance and transmittance than those of the pure PEDOT:PSS layer. Consequently, the Ir(ppy)3-based green OLEDs adopting PEDOT:PSS:AMQSs as the HIL show a lower turn-on voltage of 3.0 V and achieve a dramatically higher device efficiency. Particularly, the optimized AMQS-based OLED realizes the maximum current efficiency (CE), power efficiency (PE) and external quantum efficiency (EQE) of 69.88 cd A−1, 48.28 lm W−1 and 19.91%, respectively, which are 14.86%, 68.99% and 13.32% higher than those of the reference device. The remarkable improvements are mainly ascribed to the two-dimensional electronic structure of AMQSs, which enhances the hole injection, transport capability, and boosts the light extraction efficiency. These findings point out a novel strategy to develop high-performance OLEDs by using two-dimensional quantum sheets.
研究领域:
材料科学
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光电器件
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纳米技术
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2020
·
IF 6.155
Kai Huang,Yuyang Xu,Yanpeng Song,Ruyue Wang,Hehe Wei,Yuanzheng Long,Ming Lei,Haolin Tang,Jiangang Guo,Hui Wu
Electrocatalysts for oxygen reduction reactions (ORR) and oxygen evolution reactions (OER) are highly crucial and challenging toward the energy storage and conversion technologies such as fuel cells, metal-air batteries and water electrolysis. To replace noble-metal based catalysts and boost catalytic performance of carbon-based materials, we initially develop the nickel, phosphorus, sulfur and nitrogen co-modified mesoporous carbon (NiPS 3 @NMC) as a bifunctional oxygen electrocatalyst. The performance for ORR (half-wave potential at 0.90 V) and OER (10 mA cm −2 at 1.48 V) surpasses those of Pt/C coupled with IrO 2 catalysts and most of the non-precious metal based bifunctional electrocatalysts reported in related literature. Moreover, the electrochemical durability is also confirmed by accelerated durability tests (ADTs) and long-term chronoamperometry (CA) tests. We demonstrated that the interfacial effect between NiPS 3 quantum sheets (QSs) and NMC substrates by thermal activation contributed to the enhanced oxygen electrode bifunctionality with more active sites, due to the electrons-donating from nickel, phosphorus and sulfur elements and relatively enriched pyridinic type N. Such excellent overall performance highlights the potential application of NiPS 3 QSs and NMC composites as the materials on energy conversion and storage.
研究领域:
能源材料科学
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电化学
✓ 已验证
DOI
高影响因子
2D Materials
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2019
·Vol. 6
·期 4
·045017
·
IF 7.343
Zhongqiang Wang,Zhiyuan Wang,Zongtao Wang,Min Zhao,Yingjuan Zhou,Bo Zhao,Yanqin Miao,Peizhi Liu,Yuying Hao,Hua Wang,Bingshe Xu,Yucheng Wu,Shougen Yin
In this work, soluble two-dimensional (2D) material of antimonene quantum sheets (AMQSs) is used to form a bilayer hole extraction layer (HEL) with CuSCN. It proves that the application of AMQSs helps to passivate surface defects of CuSCN, resulting in diminished recombination loss and depressed exciton quenching effect, and thereby achieving improved photovoltaic performance. In OPVs based on poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b;4,5-b']dithiophene-2,6-diyl-alt-(4-(2-ethylhexyl)-3-fluorothieno[3,4-b]thiophene-)-2-carboxylate-2-6-diyl)]: [6,6]-phenyl C71-butyric acid methyl ester (PTB7-Th:PC71BM), over 12% enhancement of power conversion efficiency (PCE) is observed compared to that of the reference cell fabricated with pure CuSCN as an HEL. The advantage of the bilayer CuSCN/AMQS HEL is also confirmed in non-fullerene systems of PBDB-T-2F:IT-4F and PTB7-Th:ITIC. In a cell based on PBDB-T-2F:IT-4F, a PCE of 10.14% was obtained after application of AMQSs, which improved by about 10% compared to that of the reference cell using pure CuSCN as an HEL. Furthermore, cells based on CuSCN and CuSCN/AMQS HEL exhibit superior air stability. The use of a bilayer CuSCN/AMQS HEL provides a promising approach to obtain efficient and stable organic solar cells.
研究领域:
材料科学
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光伏技术
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有机电子学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Zhangqiang Li,Zhexue Chen,Liuyang Xiao,Xuanping Zhou,Ce Zhao,Yong Zhang
Molybdenum disulfide (MoS2) quantum sheets (QSs) are attractive for applications due to their tunable energy band structures and optical and electronic properties. The photoluminescence quantum yield (PLQY) of MoS2 QSs achieved by mechanical and liquid exfoliation and chemical vapor deposition is low. Some studies have reported that chemical treatment and elemental doping can improve the PLQY of transition metal dichalcogenides (TMDs), but this is limited by complex instruments and reactions. In this study, a heat treatment method based on a polar solvent is reported to improve the PLQY and photoluminescence (PL) intensity of MoS2 QSs at room temperature. The absolute PLQY of treated MoS2 QSs is increased to 18.5%, and the PL intensity is increased by a factor of 64. This method is also effective for tungsten disulfide (WS2) QSs. The PL enhancement of QSs is attributed to oxidation of the edges. Such passivation/deformation of MoS2 QSs facilitates the radiative route rather than the nonradiative route, resulting in extreme enhancement of the PL. Our work could provide novel insights/routes toward the PL enhancement of TMD QSs.
研究领域:
材料科学
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纳米技术
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光电
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2018
·Vol. 6
·期 46
·23773-23779
·
IF 9.931
Zhiyuan Wang,Ruqin Zhang,Min Zhao,Zhongqiang Wang,Bingwei Wei,Xuefeng Zhang,Shuai Feng,Hailiang Cao,Peizhi Liu,Yuying Hao,Hua Wang,Bingshe Xu,Stephen J. Pennycook,Junjie Guo
High-performance organic photovoltaics (OPVs) are of great scientific and technological importance due to their potential large-scale industrial applications. Introducing semiconductor quantum dots has been proven to be an effective way to improve the power conversion efficiency (PCE) of OPVs. In this paper, we report a novel approach to fabricate atomically thin antimonene quantum sheets (AMQSs) possessing a uniform size (≈2.2 nm) via imidazolium ionic liquid-assisted exfoliation. In this method, the yield of AMQSs (1.1 mg mL−1) has been increased by nearly two orders of magnitude compared with that of previously reported methods. Furthermore, upon adding AMQSs into the light absorber in OPVs, the optimal device with 1.0 mg mL−1 AMQSs shows the highest PCE of 9.75%, resulting in over 25% enhancement in PCE compared to that of the reference device. It also leads to a noticeable enhancement in the short-circuit current density (Jsc) of 16.7% and the fill factor (FF) of 8.4%. The increased PCE is mainly due to the two-dimensional electronic structure of AMQSs that can enhance the light absorption, assist exciton dissociation and reduce charge recombination of OPVs. This work provides a new avenue toward mass production of two-dimensional quantum sheets and points to a new strategy for highly efficient OPVs.
研究领域:
材料科学
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纳米科技
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光伏技术
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半导体物理
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能源材料
✓ 已验证
DOI
高影响因子
Nature Nanotechnology
·
2021
·Vol. 17
·期 2
·153-158
·
IF 39.213
Chen Wenshu,Gu Jiajun,Liu Qinglei,Yang Mengzhao,Zhan Cheng,Zang Xining,Pham Tuan Anh,Liu Guangxiang,Zhang Wang,Zhang Di,Dunn Bruce,Morris Wang Y.
Dense, thick, but fast-ion-conductive electrodes are critical yet challenging components of ultrafast electrochemical capacitors with high volumetric power/energy densities 1 , 2 , 3 , 4 . Here we report an exfoliation–fragmentation–restacking strategy towards thickness-adjustable (1.5‒24.0 μm) dense electrode films of restacked two-dimensional 1T-MoS 2 quantum sheets. These films bear the unique architecture of an exceptionally high density of narrow (sub-1.2 nm) and ultrashort (~6.1 nm) hydrophobic nanochannels for confinement ion transport. Among them, 14-μm-thick films tested at 2,000 mV s −1 can deliver not only a high areal capacitance of 0.63 F cm −2 but also a volumetric capacitance of 437 F cm −3 that is one order of magnitude higher than that of other electrodes. Density functional theory and ab initio molecular dynamics simulations suggest that both hydration and nanoscale channels play crucial roles in enabling ultrafast ion transport and enhanced charge storage. This work provides a versatile strategy for generating rapid ion transport channels in thick but dense films for energy storage and filtration applications.
研究领域:
材料科学
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电化学
·
纳米技术
·
能源存储
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）