已为您找到该学者40条结果 成果回收站
Nano Energy,2016,25():34-41
2016年07月01日
Black phosphorene (BP), a newly discovered elemental two-dimensional material, is attractive for optoelectronic and photonic applications because of its unique in-plane anisotropy, thickness-dependent direct bandgap and high carrier mobility. Since its discovery, black phosphorene has become an appealing candidate well-suited for polarization-resolved near- and mid-infrared optoelectronics due to its relative narrow bandgap and asymmetric structure. Here, we employ benzyl viologen (BV) as an effective electron dopant to part of the area of a (p-type) few-layer BP flake and achieve an ambient stable, in-plane P–N junction. Chemical doping with BV molecules modulates the electron density and allows acquiring a large built-in potential in this in-plane BP P–N junction, which is crucial for achieving high responsivity photodetectors and high quantum efficiency solar cells. As a demonstrative example, by illuminating it with a near-infrared laser at 1.47 µm, we observe a high responsivity up to ~180 mA/W with a rise time of 15 ms, and an external quantum efficiency of 0.75%. Our strategy for creating environmentally stable BP P–N junction paves the way to implementing high performance BP phototransistors and solar cells, which is also applicable to other 2D materials.
Few-layer black phosphorene Chemical doping P–N junction Photodetector Solar cells
0
-
9浏览
-
0点赞
-
0收藏
-
0分享
-
0下载
-
0
-
引用
Phys. Rev. B,2016,93(24):245303
2016年06月15日
A stibarsen [derived from Latin stibium (antimony) and arsenic] or allemontite, is a natural form of arsenic antimonide (SbAs) with the same layered structure as arsenic and antimony. Thus, exploring the two-dimensional SbAs nanosheets is of great importance to gain insights into the properties of group V-V compounds at the atomic scale. Here, we propose a class of two-dimensional V-V honeycomb binary compounds, SbAs monolayers, which can be tuned from semiconductor to topological insulator. By ab initio density functional theory, both α-SbAs and γ-SbAs display a significant direct band gap, while others are indirect semiconductors. Interestingly, in an atomically thin β-SbAs polymorph, spin-orbital coupling is significant, which reduces its band gap by 200 meV. Especially under biaxial tensile strain, the gap of β-SbAs can be closed and reopened with concomitant change of band shapes, which is reminiscent of band inversion known in many topological insulators. In addition, we find that the Z2 topological invariant is 1 for β-SbAs under the tensile strain of 12%, and the nontrivial topological feature of β-SbAs is also confirmed by the gapless edge states which cross linearly at the Γ point. These ultrathin group-V-V semiconductors with outstanding properties are highly favorable for applications in alternative optoelectronic and quantum spin Hall devices.
无
0
-
40浏览
-
0点赞
-
0收藏
-
0分享
-
0下载
-
0
-
引用
Advanced Functional Materials,2016,26(32):5903-5912
2016年06月14日
The strong ionic character endows all‐inorganic CsPbX3 (X = Cl, Br, I) perovskite nanocrystals (NCs) with different chemical features from classical Cd‐based NCs, especially when considering their interaction with polar solvents and surfactants. This has aroused intensive interest, but is still short of comprehensive understanding. More significantly, above characteristic may be used to improve the quality of perovskite thin films, which is crucial for the carrier transport inside optoelectronic devices. Here, an interesting recyclable dissolution–recyrstallization phenomenon of all‐inorganic pervoskite, as well as its application on room temperature (RT) self‐healing of compact and smooth carrier channels in ambient atmosphere for high‐performance PDs with high stability is reported. First, according to solubility equilibrium principle, the size of CsPbBr3 crystals can be reversibly tuned in the range of 10 nm–1 μm through washing with polar solvent or stirring with assistance of surfactants at RT. Second, such phenomenon is applied for significant film quality improvement by forming a liquid circumstance within films, which can transport matter at surface and sharp parts into the gaps, healing themselves at RT. This strategy results in large‐area, crack‐free, low‐roughness perovskite thin films. Obviously, such improvement facilitates transport and extraction of carriers in the channels of devices, which has been evidenced by the improvement of performances of the corresponding PDs at ambient condition.
无
0
-
52浏览
-
0点赞
-
0收藏
-
1分享
-
0下载
-
0
-
引用
Advanced Functional Materials,2016,26(28):5051-5060
2016年05月18日
Ternary oxide nanocrystals (TONs) have received growing attention for their great potential applications in optoelectronics and electrochemistry despite the current scarcity of universal, facile, and green synthesis methods. Here, we introduce a universal laser‐hydrothermal approach for various TONs and demonstrate their potential for high‐performance photodetectors (PDs) and pseudocapacitors. The obtained clean surface is derived by laser ablation in liquid (LAL) and subsequent hydrothermal growth. The LAL‐generated precursors contain many kinds of highly reactive species, including H+, OH−, metal ions, and clusters, which facilitate the fast and facile formation of various TONs in the subsequent hydrothermal process. The universality of the method is systematically proven by the synthesis of a series of TONs, including Zn2GeO4, NiCo2O4, Zn2SnO4, ZnFe2O4, ZnMnO3, and Fe2GeO4. Significantly, the absence of chemical additives, such as surfactants, guarantees highly clean surfaces, which further benefits the electron transport through the nanocrystals, and thus in the resultant devices. This is also exemplified by a Zn2GeO4‐nanorod‐based, deep‐ultraviolet PD and NiCo2O4 nanocrystal supercapacitors.
无
0
-
99浏览
-
0点赞
-
0收藏
-
1分享
-
0下载
-
0
-
引用
Advanced Materials,2016,28(24):4861-4869
2016年04月25日
Printed flexible photodetectors based on 2D inorganic perovskites with atomic thickness show excellent photosensing with fast rise and decay response times. As‐synthesized nanosheets can easily be dispersed in various solvents, leading to large‐area, crack‐free, low‐roughness, flexible films after printing. This study demonstrates that all‐inorganic perovskite CsPbX3 nanosheets as a new class of 2D semiconductors have huge potential for flexible optoelectronic applications.
无
0
-
38浏览
-
0点赞
-
0收藏
-
1分享
-
0下载
-
0
-
引用
合作学者
- 暂无合作作者