二维黑磷的制备及光电器件研究进展

黑磷有随层数可调的直接带隙和独特的各向异性结构等众多优异的性质,因此近年来受到科研人员的广泛关注。本文概述了二维黑磷的制备方法,重点综述了黑磷独特的非线性光学性质、各向异性光学性质及它在光电器件中的应用。最后,对黑磷的应用前景与一些亟待解决的问题做了简单的讨论。     

二维黑磷的制备及光电器件研究进展

黑磷有随层数可调的直接带隙和独特的各向异性结构等众多优异的性质,因此近年来受到科研人员的广泛关注.本文概述了二维黑磷的制备方法,重点综述了黑磷独特的非线性光学性质、各向异性光学性质及它在光电器件中的应用.最后,对黑磷的应用前景与一些亟待解决的问题做了简单的讨论.     

二维黑磷物理性质及化学稳定性的研究进展

1914年科研工作者首次合成了黑磷的块体形式。在黑磷沉寂了100年之后,2014年人们成功地将其薄化到少层状态,得到了新型二维纳米材料——二维黑磷。它是由磷原子堆叠而成的单一元素的二维层状半导体材料,具有合适的可控直接带隙、高的载流子迁移率、高的漏电流调制率、较高的开关电流比、良好的导电导热能力和明显的平面各向异性等性质,在低维无机半导体领域备受关注。二维黑磷是一种具有众多优异性质的内禀p型材料,但在空气中的不稳定性使得目前还不能分离得到大面积磷烯(即单原子层黑磷)薄膜,这限制了二维黑磷的应用。本文综述了自2014年以来国内外关于二维黑磷的研究进展,系统介绍了二维黑磷的结构、制备与性质,重点归纳了包括电学性质、光学性质、力学性质、热学性质和磁学性质在内的物理性质及化学稳定性。最后总结并展望了二维黑磷作为电子材料的广阔前景。     

黑磷及黑磷烯在储能领域的应用研究进展

黑磷是一种结构类似于石墨的层状材料,单原子层厚的黑磷被称为黑磷烯。黑磷及黑磷烯在储能领域具有很好的应用前景。详细介绍了黑磷、黑磷烯及其复合材料在二次电池、超级电容器中的应用研究现状,并对其发展前景进行了展望。     

黑磷在离子电池中的应用研究进展

新型纳米材料黑磷呈二维折叠层状结构,具有独特的光电特性,其理论容量大、载流子迁移率高、氧化还原电位低、带隙可调,在电化学储能、光催化制氢、癌症靶向治疗等领域应用前景广阔。尤其是在电化学储能领域,因其高达2 596 mAh/g的理论比容量,已被作为锂离子电池与钠离子电池的负极材料得到了广泛的应用,是可充电电池理想的负极材料之一。综述了黑磷在离子电池领域的应用,旨在为后续黑磷的结构设计奠定基础,为储能领域蓬勃发展铺平道路。     

黑磷烯的制备及其非线性光学性质研究进展

新材料的研制和应用是21世纪材料科学和物理科学发展的重要方向之一。黑磷烯作为一种新兴的二维材料,具有可调谐的直接带隙和宽波带非线性吸收等独特性质,其非线性光学性质及制备引起了研究人员的广泛兴趣。首先介绍了几种黑磷烯的制备方法,包括高压法、铋熔化法、高能球磨法、低压矿化法与热气化法,并分析了各方法的优劣。其次介绍了黑磷烯纳米片与黑磷量子点的非线性光学研究进展,及其在锁模激光器中的应用。最后,对黑磷烯的制备方法和非线性光学性质研究的进一步发展做出了展望。     

复旦大学成功制备新型二维晶体黑磷

正近日,复旦大学物理系张远波教授课题组的李力恺、於逸骏与合作者们成功制备了基于新型二维晶体黑磷的场效应晶体管器件。相关学术论文《Black Phosphorus Fieldeffect Transistors》(《黑磷场效应晶体管》)在《自然·纳米技术》(Nature Nanotechnology)上发表(DOI:10.1038/nnano.2014.35)。二维晶体黑磷是继石墨烯、二硫化钼之后的又一重要的研究进展,为二维晶体材料家族增添     

石墨烯/黑磷纳米复合粒子对环氧树脂阻燃与热稳定性能的影响

近年来,具有蜂窝状褶皱片层结构的黑磷(BP)在阻燃高分子复合材料领域展现出潜在的应用前景.本工作采用高能球磨方法制备出石墨烯/黑磷纳米复合粒子(G-BP),以拉曼光谱与X射线衍射表征其结构,并利用极限氧指数(LOI)、UL 94垂直燃烧测试和热重分析探究G-BP含量对环氧树脂基体热稳定性与阻燃性能的影响.结果表明:在环氧树脂中添加2％G-BP,其高温残炭量从14.8％提高至25.3％,LOI提高至25.5％,且UL 94垂直燃烧等级达到V1级;G-BP添加量为5％时,环氧树脂的LOI达27.5％,且UL 94垂直燃烧等级通过V0级.G-BP通过气固双相阻燃协同机理,明显改善了环氧树脂的成炭性与阻燃性.     

单层黑磷和蓝磷扩展分子结的电子输运特性

本工作应用非平衡格林函数理论和密度泛函理论研究了二维材料单层黑磷扩展分子结和蓝磷扩展分子结的电子输运特性,以及在应力作用下能隙和伏安特性的变化特点。结果发现,两种扩展分子结在发生应变(拉伸和压缩)过程中,随着应变(拉伸和压缩)的增加,HOMO能量和LUMO能量逐步靠近,导致能隙逐渐降低,分别减小了0.67eV和1.33eV。能隙降低,同时导通轨道间隔和导通轨道迁移率也降低,导致伏安特性曲线中量子化台阶逐渐消失,出现了类似金属的I-V曲线特点。此外,单层黑磷扩展分子结在0.75~2.00V范围内产生稳定电流,有望应用于电路中的稳流装置。     

我国科学家应向黑磷进军

正科学家应该在石墨烯、黑磷等新材料领域不断发力,把握先机,争取实现对国际同行的赶超,成为该领域的"开拓者"和"引领者"。众所周知,新材料的使用,能够给很多领域带来革命性的变化。比如,当前如火如荼的石墨烯,就被誉为"黑金""新材料之王",科学家甚至预言石墨烯将"彻底改变21世纪"。近年来,另外一种和石墨烯有着类似性质的新材料——黑磷的重要性也日益凸显,被科学家和企业界看好。所幸的是,在黑磷的基础研究和应用方面,来自中国的科学家走在     

Phosphorene and Phosphorene‐Based Materials – Prospects for Future Applications

Phosphorene, a single‐ or few‐layered semiconductor material obtained from black phosphorus, has recently been introduced as a new member of the family of two‐dimensional (2D) layered materials. Since its discovery, phosphorene has attracted significant attention, and due to its unique properties, is a promising material for many applications including transistors, batteries and photovoltaics (PV). However, based on the current progress in phosphorene production, it is clear that a lot remains to be explored before this material can be used for these applications. After providing a comprehensive overview of recent advancements in phosphorene synthesis, advantages and challenges of the currently available methods for phosphorene production are discussed. An overview of the research progress in the use of phosphorene for a wide range of applications is presented, with a focus on enabling important roles that phosphorene would play in next‐generation PV cells. Roadmaps that have the potential to address some of the challenges in phosphorene research are examined because it is clear that the unprecedented chemical, physical and electronic properties of phosphorene and phosphorene‐based materials are suitable for various applications, including photovoltaics.     

2D Black Phosphorus for Energy Storage and Thermoelectric Applications

Recent progress in the currently available methods of producing black phosphorus bulk and phosphorene are presented. The effective passivation approaches toward improving the air stability of phosphorene are also discussed. Furthermore, the research efforts on the phosphorene and phosphorene‐based materials for potential applications in lithium ion batteries, sodium ion batteries, and thermoelectric devices are summarized and highlighted. Finally, the outlook including challenges and opportunities in these research fields are discussed.     

Thermal Transport in Phosphorene

Phosphorene, a novel elemental 2D semiconductor, possesses fascinating chemical and physical properties which are distinctively different from other 2D materials. The rapidly growing applications of phosphorene in nano/optoelectronics and thermoelectrics call for comprehensive studies of thermal transport properties. In this Review, based on the theoretical and experimental progresses, the thermal transport properties of single‐layer phosphorene, multilayer phosphorene (nanofilms), and bulk black phosphorus are summarized to give a general view of the overall thermal conductivity trend from single‐layer to bulk form. The mechanism underlying the discrepancy in the reported thermal conductivity of phosphorene is discussed by reviewing the effect of different functionals and cutoff distances on the thermal transport evaluations. This Review then provides fundamental insight into the thermal transport in phosphorene by reviewing the role of resonant bonding in driving giant phonon anharmonicity and long‐range interactions. In addition, the extrinsic thermal conductivity of phosphorene is reviewed by discussing the effects of strain and substrate, together with phosphorene based heterostructures and nanoribbons. This Review summarizes the progress of thermal transport in phosphorene from both theoretical calculations and experimental measurements, which would be of significance to the design and development of efficient phosphorene based nanoelectronics.     

Defect Engineering in Few‐Layer Phosphorene

Defect engineering in 2D phosphorene samples is becoming an important and powerful technique to alter their properties, enabling new optoelectronic applications, particularly at the infrared wavelength region. Defect engineering in a few‐layer phosphorene sample via introduction of substrate trapping centers is realized. In a three‐layer (3L) phosphorene sample, a strong photoluminescence (PL) emission peak from localized excitons at ≈1430 nm is observed, a much lower energy level than free excitonic emissions. An activation energy of ≈77 meV for the localized excitons is determined in temperature‐dependent PL measurements. The relatively high activation energy supports the strong stability of the localized excitons even at elevated temperature. The quantum efficiency of localized exciton emission in 3L phosphorene is measured to be approximately three times higher than that of free excitons. These results could enable exciting applications in infrared optoelectronics.     

Fluorinated Phosphorene: Electrochemical Synthesis,Atomistic Fluorination,and Enhanced Stability

Phosphorene has attracted great interest due to its unique electronic and optoelectronic properties owing to its tunable direct and moderate band‐gap in association with high carrier mobility. However, its intrinsic instability in air seriously hinders its practical applications, and problems of technical complexity and in‐process degradation exist in currently proposed stabilization strategies. A facile pathway in obtaining and stabilizing phosphorene through a one‐step, ionic liquid‐assisted electrochemical exfoliation and synchronous fluorination process is reported in this study. This strategy enables fluorinated phosphorene (FP) to be discovered and large‐scale, highly selective few‐layer FP (3?6 atomic layers) to be obtained. The synthesized FP is found to exhibit unique morphological and optical characteristics. Possible atomistic fluorination configurations of FP are revealed by core‐level binding energy shift calculations in combination with spectroscopic measurements, and the results indicate that electrolyte concentration significantly modulates the fluorination configurations. Furthermore, FP is found to exhibit enhanced air stability thanks to the antioxidation and antihydration effects of the introduced fluorine adatoms, and demonstrate excellent photothermal stability during a week of air exposure. These findings pave the way toward real applications of phosphorene‐based nanophotonics.     

Layer‐Tunable Phosphorene Modulated by the Cation Insertion Rate as a Sodium‐Storage Anode

Liquid phase exfoliation of few‐layer phosphorene (FL‐P) is extensively explored in recent years. Nevertheless, their deficiencies such as ultralong sonication time, limited flake size distribution, and uncontrollable thicknesses are major hurdles for the development of phosphorene‐based materials. Herein, electrochemical cationic intercalation has been introduced to prepare phosphorene, through which large‐area FL‐P without surface functional groups can be efficiently attained (less than 1 h). More importantly, its layer number (from 2 to 11 layers) can be manipulated by changing the applied potential. The as‐obtained phosphorene delivers superior sodium‐storage performances when directly utilized as an anode material in sodium‐ion batteries. This electrochemical cation insertion method to prepare phosphorene should greatly facilitate the development of phosphorene‐based technologies. Moreover, this work provides the possibility for the scalable preparation of monolayer 2D materials by exploring intercalation ions. Additionally, the successful electrochemical exfoliation of phosphorene can promote the application of electrochemical exfoliation in other 2D materials.     

Plasma-assisted fabrication of monolayer phosphorene and its Raman characterization

There have been continuous efforts to seek novel functional two-dimensional semiconductors with high performance for future applications in nanoelectronics and optoelectronics. In this work, we introduce a successful experimental approach to fabricate monolayer phosphorene by mechanical cleavage and a subsequent Ar＊ plasma thinning process. The thickness of phosphorene is unambiguously determined by optical contrast spectra combined with atomic force microscopy （AFM）. Raman spectroscopy is used to characterize the pristine and plasma-treated samples. The Raman frequency of the A2g mode stiffens, and the intensity ratio of A2g to Alg modes shows a monotonic discrete increase with the decrease of phosphorene thickness down to a monolayer. All those phenomena can be used to identify the thickness of this novel two-dimensional semiconductor. This work on monolayer phosphorene fabrication and thickness determination will facilitate future research on phosphorene.     

Black Phosphorus,a Rising Star 2D Nanomaterial in the Post‐Graphene Era: Synthesis,Properties, Modifications,and Photocatalysis Applications

Semiconductor photocatalysis, a sustainable and renewable technology, is deemed to be a new path to resolve environmental pollution and energy shortage. The development of effective photocatalysts, especially the metal‐free photocatalysts, is a critical determinant of this technique. The recently emerged 2D material of black phosphorus with distinctive properties of tunable direct bandgap, ultrahigh charge mobility, fortified optical absorption, large specific surface area, and anisotropic structure has captured enormous attention since the first exfoliation of bulk black phosphorus into mono‐ or few layered phosphorene in 2014. In this article, the state‐of‐the‐art preparation methods are first summarized for bulk black phosphorus, phosphorene, and black phosphorus quantum dot and then the fundamental structure and electronic and optical properties are analyzed to evaluate its feasibility as a metal‐free photocatalyst. Various modifications on black phosphorus are also summarized to enhance its photocatalytic performance. Furthermore, the multifarious applications such as solar to energy conversion, organic removal, disinfection, nitrogen fixation, and photodynamic therapy are discussed and some of the future challenges and opportunities for black phosphorus research are proposed. This review reveals that the rising star of black phosphorus will be a multifunctional material in the postgraphene era.     

Three-layer phosphorene-metal interfaces

Phosphorene has attracted much attention recently as an alternative channel material in nanoscale electronic and optoelectronic devices due to its high carrier mobility and tunable direct bandgap. Compared with monolayer (ML) phosphorene, few-layer (FL) phosphorene is easier to prepare, is more stable in experiments, and is expected to form a smaller Schottky barrier height (SBH) at the phosphorene-metal interface. Using ab initio electronic structure calculations and quantum transport simulations, we perform a systematic study of the interfacial properties of three-layer (3L) phosphorene field effect transistors (FETs) contacted with several common metals (Al, Ag, Au, Cu, Ti, Cr, Ni, and Pd) for the first time. The SBHs obtained in the vertical direction from projecting the band structures of the 3L phosphorene-metal systems to the left bilayer (2L) phosphorenes are comparable with those obtained in the lateral direction from the quantum transport simulations for 2L phosphorene FETs. The quantum transport simulations for the 3L phosphorene FETs show that 3L phosphorene forms n-type Schottky contacts with electron SBHs of 0.16 and 0.28 eV in the lateral direction, when Ag and Cu are used as electrodes, respectively, and p-type Schottky contacts with hole SBHs of 0.05, 0.11, 0.20, 0.30, 0.30, and 0.31 eV in the lateral direction when Cr, Pd, Ni, Ti, Al, and Au are used as electrodes, respectively. The calculated polarity and SBHs of the 3L phosphorene FETs are generally in agreement with the available experiments.

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Effects of substrate and environmental adsorbates on the electronic properties and structural stability of antimonene

The structural stability of some two-dimensional materials at ambient conditions is obviously attributed to their low sensitivity to exposure of humidity and air. Recently exfoliated antimonene, differently from another group-VA material, phosphorene, possesses a high structural integrity at ambient conditions. Considering the kinship of phosphorene and antimonene, there is a need to comprehensively examine the interaction of the H₂O and O₂ molecules with the antimonene surface to understand the difference in the structural stability of these materials. The calculations predict that antimonene, similarly to phosphorene, shows higher affinity to oxygen rather than water. Surprisingly, for antimonene, the barrier for the O–O bond splitting to form O–Sb bonds is found to be much lower than that of for phosphorene. However, antimonene, in contrast to phosphorene, preserves structural integrity upon oxidation which may be attributed to a stronger interaction and hybridization of atoms in antimonene compared to the atoms in phosphorene. In addition, the oxidation ability of antimonene can be significantly controlled by the graphene and BN substrates.