2Dgroup-VAfluorinatedantimonene:synthesisandsaturableabsorption资源-CSDN文库

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本研究论文的主题是“2D group-VA氟化锑烯：合成与饱和吸收”，主要探讨了采用离子液体辅助电化学剥离和同步氟化的方法合成氟化锑烯新材料，并对其作为饱和吸收体的应用进行了研究。论文首先介绍了二维材料的背景，自石墨烯的发现以来，二维材料因其独特的性质，在物理、化学和材料科学领域引起了广泛的关注。这些性质包括高迁移率、出色的机械性能等。此外，二维材料在电子和光电子设备、生物系统、热管理等领域具有巨大的应用潜力。在2D group-V Amaterials（第V主族A族二维材料）的研究领域，氟化锑烯作为一种新材料，拓展了除了石墨烯、拓扑绝缘体和过渡金属二硫化物之外的二维材料群。这类材料具有特定的外层电子排布，即a3s23p3壳层。单层结构的存在依赖于sp3杂化态，从而影响材料的物理和化学性质。氟化锑烯是锑烯的一个新衍生物，其特征是具有直接带隙，这与纯锑烯的间接带隙不同。这种带隙的变化是由氟化程度调控的，这表明氟化锑烯除了作为饱和吸收体外，还可以应用于其他光学设备。在论文中，研究团队通过密度泛函理论计算揭示了氟化程度对带隙的调控作用。他们进一步研究了氟化锑烯作为饱和吸收体在激光器中的应用，通过Nd:LuAG激光器产生的被动Q开关脉冲，获得了326.7纳秒的脉冲宽度和733.1千赫兹的重复率，证实了氟化锑烯作为一种饱和吸收体的潜力。这一发现不仅证实了氟化锑烯作为饱和吸收体的应用前景，而且还展示了其在光学设备领域的应用潜力。论文还提到了氟化锑烯的合成方法——离子液体辅助电化学剥离法和同步氟化法。这种合成方法可能是制备其他二维材料的一种有效途径，并可能引导科学家探索新的二维材料家族。论文的作者包括Guangju Zhang, Han Zhang, Qiang Liu, Mali Gong等人，他们分别来自清华大学精密仪器系光电子与电子学中心、深圳工程实验室、光电科学与技术创新中心和相关的重点实验室。文章被《Nanoscale》期刊接受发表，并提供了DOI标识。论文的接收日期为2018年12月19日，提交日期为2018年9月28日。这篇论文的引用信息也被给出，以便读者查询和进一步研究。从这项研究中我们可以了解到，氟化锑烯作为一种新型二维材料，其独特的光电特性使其成为未来光电器件、传感器和能源存储设备研究的新热点。其在光电子学和光子学领域的应用前景，将会吸引更多的材料科学家和工程师参与到相关研究工作中来，有望推动二维材料在现代科技中的应用步伐。

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Nanoscale

PAPER

Cite this: Nanoscale, 2019, 11, 1762

Received 28th September 2018,

Accepted 19th December 2018

DOI: 10.1039/c8nr07894g

rsc.li/nanoscale

2D group-VA ﬂuorinated antimonene: synthesis

and saturable absorption†

Guangju Zhang, ‡

Xian Tang,‡

Xing Fu,

Weicheng Chen,

Babar Shabbir,

Han Zhang, *

Qiang Liu*

and Mali Gong*

A new derivative of antimonene named ﬂuorinated antimonene was synthesized using the method of

ionic liquid-assisted electrochemical exfoliation and synchronous ﬂuorination. Passive Q-switched pulses

were produced from a Nd:LuAG laser with ﬂuorinated antimonene, having a pulse width of 326.7 ns and a

repetition rate of 733.1 kHz demonstrating its potential application as a saturable absorber. Density func-

tional theory calculations revealed that compared with pure antimonene with an indirect bandgap, ﬂuori-

nated antimonene exhibits a direct bandgap modulated by the ﬂuorination degree showing that ﬂuori-

nated antimonene would be applied as optical devices beyond its application as a saturable absorber.

Introduction

Since the discovery of graphene, 2D materials have attracted

extensive attention in physics, chemistry and materials science

due to their unusual and outstanding properties including

high mobility,

excellent mechanical performance,

and so

forth. Beyond the scientific research revealing these properties,

great potential applications of 2D materials, such as electronic

and optoelectronic devices,

3–5

biosystems,

and thermal man-

agement,

motivate scientists to explore new families of 2D

materials. 2D group-VA materials are the most recently discov-

ered which have expanded the 2D material community besides

graphene, topological insulators and transition-metal dichal-

cogenides (TMDs).

2D group-VA materials possess a 3s

outmost shell, and the existence of the sp

-hybridized states

depends on the monolayer structures. In the buckled honey-

comb monolayer, sp

-hybridizations may be partially formed

between in-plane sp

and out-of-plane p

orbitals. If the mono-

layer has a flat honeycomb structure, no sp

-hybridizations will

exist.

This endows 2D group-VA materials with some unique

properties and potential applications compared to other 2D

materials. For example, their electronic bandgap varying

between 0.36 and 2.62 eV can be determined by the thickness,

which would inspire great potential for applications emphasiz-

ing a broadband photoresponse.

Saturable absorption of light widely exists in 2D

materials.

10–26

Nowadays, considering the importance of

pulsed lasers in science and technology, this property endows

2D materials with extremely high values in related research

studies. As TMDs normally possess a moderate bandgap (1 eV

for bulk and 2 eV for the monolayer

27,28

) compared to 2D

group-VA materials, in theory, 2D group-VA materials have

saturable absorption in a wider spectral region compared to

TMDs, which has been demonstrated by phosphorene, the

firstly discovered 2D group-VA material.

Recent research

studies have determined phosphorene to have excellent satur-

able absorption spanning from 0.4 to 3 μm by adopting it as a

saturable absorber (SA) in pulsed lasers.

30–33

On the other

hand, as the firstly and most intensively studied SA in 2D

materials, graphene possesses a relatively weak absorption in

the monolayer than phosphorene.

27,34,35

However, the intrinsic

instability of phosphorene has been an essential obstacle hin-

dering its long-term use.

Most recently, the 2D group-VA

family has been expanded to include arsenene,

9,37

antimonene

8,38–43

and bismuthene,

10,44–46

and antimonene

has been found to possess robust ambient stability.

In pre-

vious research studies,

11,39

few-layer antimonene was revealed

to be beneficial for developing antimonene-based and broad-

band-photoresponse devices in passive Q-switched (QS) solid-

† Electronic supplementary information (ESI) available: Snapshots of the syn-

thesis process, large-area AFM image, electronic structures, and photo-

luminescence spectrum of fluorinated antimonene. See DOI: 10.1039/

c8nr07894g

‡ These authors contribute equally to this work.

Center for Photonics and Electronics, Department of Precision Instruments,

Tsinghua University, Beijing 100084, China. E-mail: qiangliu@mail.tsinghua.edu.cn,

gongml@mail.tsinghua.edu.cn

Shenzhen Engineering Laboratory of Phosphorene and Optoelectronics,

Collaborative Innovation Center for Optoelectronics Science and Technology, and Key

Laboratory of Optoelectronics Devices and Systems of Ministry of Education and

Guangdong Province, Shenzhen University, Shenzhen 518060, China.

E-mail: hzhang@szu.edu.cn

School of Physics and Optoelectronic Engineering, Foshan University, Foshan

528000, China

Department of Materials Science and Engineering, and ARC Centre of Excellence in

Future Low-Energy Electronics Technologies (FLEET), Monash University, Clayton,

VIC 3800, Australia

1762 | Nanoscale,2019,11,1762–1769 This journal is © The Royal Society of Chemistry 2019

Published on 20 December 2018. Downloaded by Shenzhen University on 3/6/2019 2:03:03 AM.

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state lasers,

ultrafast microfiber lasers and all-optical pulse

thresholders.

In addition, density functional theory (DFT) cal-

culations have predicted that monolayer antimonene possesses

an indirect bandgap lying between 0.76 and 2.28 eV,

10,41,42

whereas few-layer antimonene has a zero bandgap. Chemical

functionalization and adatom addition have been found to

induce significant spin polarization

and charge transfer

antimonene, which would be a novel pathway for tuning its

peculiar electronic properties and thus significantly modulat-

ing its optical properties.

Until now, methods to synthesize 2D group-VA materials

have included mechanical

and liquid-phase

50,51

exfoliations

as well as epitaxial growth.

52,53

In particular, using the method

of ionic liquid-assisted electrochemical exfoliation and syn-

chronous fluorination (EESF), we obtained fluorinated phos-

phorene as the derivative of 2D group-VA materials.

Through

calculations and spectroscopy measurements, the fluorination

process was demonstrated to be modulated by the electrolyte

concentration, and the photothermal stability could be

improved thanks to the antioxidation and antihydration eﬀects

of the introduced fluorine adatoms, thus providing new

insight into discovering, modulating and synthesizing 2D

group-VA materials.

Herein, we synthesized a new 2D group-

VA material derivative, fluorinated antimonene (FA), by using

the EESF method, and investigated the saturation absorption

of FA by adopting it as the SA in a Nd:LuAG laser. Passive

Q-switching operation was observed with the shortest pulse

width of 326.7 ns as well as the repetition rate of 733.1 kHz

making FA a promising SA in pulsed lasers. Experimental

results were compared with performances of other QS lasers

using various SAs suggesting that FA could be an eﬀective SA

for pulse generation. Moreover, both characterization studies

and DFT calculations demonstrated the profound modulations

for electronic structures of FA as well as the induced electronic

and optical properties by fluorination. Therefore, FA might

have great potential serving as devices far more than as SAs in

electronics and optoelectronics.

Results and discussion

Synthesis and characterization of few-layer FA

During the 80 min’s EESF process, white floccules were suc-

cessfully exfoliated from the bulk antimony substrate and dis-

persed in the 0.15 M [BMIM][PF

]/MeCN electrolyte, which was

gradually discolored from transparent to light yellow (see the

photographs of the EESF process of Fig. S1 in the ESI†). The

atomic force microscopy (AFM) image of the electrochemically

synthesized FA is shown in Fig. 1a, which mainly has a height

of 1.5–5.0 nm. An FA nanosheet was found to be 2.42 nm in

thickness, corresponding to a doubly periodic ABC-stacked

slab of rhombohedral Sb ( β-Sb) with six buckled atomic layers

(the bulk β-Sb has a monolayer thickness of 3.73 Å (ref. 41)).

The schematic atomic structure of FA is shown in Fig. 1b, with

the fluorine atoms adsorbed on the edges and surfaces as well

as intercalated into the interlayer spaces. As given in Fig. 1c,

the scanning electron microscopy (SEM) image shows that the

FA nanosheets tend to accumulate. Fig. 1d is the transmission

electron microscopy (TEM) image revealing that the surface

and edge of an FA nanosheet, with a lateral size of ∼5 μm, is

rough and irregular, ascribing to the combined eﬀects of exfo-

liation and fluorination. However, the hexagonal profile (indi-

cated by the black dashed line) is largely preserved, character-

istic of β-phase crystals. Fig. 1e is the high-resolution TEM

Fig. 1 Characterization of FA. (a) AFM images of FA. The inset shows the height proﬁle along the straight red solid line. (b) Schematic atomic struc-

ture of FA. (c) SEM, (d) TEM, and (e) HRTEM images of FA. The black dashed line in (d) denotes the hexagonal proﬁle of FA. The atomic structure of

FA in (e) is in analogy with the crystal lattice. (f) F 1s and Sb 3d XPS spectra of FA. (g) Raman spectra of FA, sonicated pure antimonene, and bulk Sb.