A5023577584- 2D Materials and Applications
- Topological Materials and Phenomena
- Graphene research and applications
- Iron-based superconductors research
- Molecular Junctions and Nanostructures
- Electronic and Structural Properties of Oxides
- Physics of Superconductivity and Magnetism
- Perovskite Materials and Applications
- Quantum Dots Synthesis And Properties
- GaN-based semiconductor devices and materials
- Corporate Taxation and Avoidance
- Semiconductor materials and devices
- Conducting polymers and applications
- Metal and Thin Film Mechanics
- Surface and Thin Film Phenomena
- ZnO doping and properties
- MXene and MAX Phase Materials
- Surface Chemistry and Catalysis
- Chalcogenide Semiconductor Thin Films
- Magnetic and transport properties of perovskites and related materials
- Ga2O3 and related materials
- Advanced Condensed Matter Physics
- Cold Atom Physics and Bose-Einstein Condensates
- Nanocluster Synthesis and Applications
- Gold and Silver Nanoparticles Synthesis and Applications
Chinese Academy of Sciences
2014-2025
Suzhou Institute of Nano-tech and Nano-bionics
2016-2025
University of Science and Technology of China
2020-2023
University of Utah
2022
Suzhou Research Institute
2021
State Key Laboratory of Low-Dimensional Quantum Physics
2013-2020
Tsinghua University
2012-2020
East China Normal University
2020
Tulane University
2019
Huazhong University of Science and Technology
2019
For the inverted organic solar cells (OSCs), interface contacts between ZnO electron transporting layer and active play an important role in device performance stability. Since solution-processed surface always contains some base or zinc salt contaminants, we explored how pH conditions influence stability of nonfullerene acceptor (NFA) cells. A tight relationship condition was established. Specifically, were improved by treating films with acid solutions but worsened after treatment. The...
We prepare single-unit-cell FeSe films on insulating SrTiO3 substrates by molecular beam epitaxy and investigate the evolution of their superconducting properties with annealing in situ scanning tunneling microscopy spectroscopy ex transport measurements. find that through an process, superconductivity 1-uc develops formation stoichiometric is further enhanced charge transfer from to films. Moreover, independent bulk property substrate, regardless whether it or conductive. Our results reveal...
The significant role of interfacial coupling in the enhancement superconductivity FeSe films on ${\mathrm{SrTiO}}_{3}$ has been widely recognized, but explicit origin this is yet to be identified. Here, by surface phonon measurements using high-resolution electron energy loss spectroscopy, we found electric field generated Fuchs-Kliewer (F-K) modes can penetrate into and strongly interact with electrons therein. mode-specific electron-phonon constant for $\ensuremath{\sim}92$ meV F-K...
Ni-rich layered oxides (LiNixMnyCozO2, x ≥ 0.6, + y z = 1) are promising positive electrode materials for high energy density lithium-ion batteries thanks to their specific capacity. However, large-scale application of is hindered by its poor structural and interfacial stability, especially during cycling at a cutoff potential (i.e., 4.3 V, versus Li+/Li). Herein, we demonstrate that lithium difluoro(oxalato)borate (LiDFOB) as film-forming additive plays dual role on the...
Oxidation of solar cells leads to Li<sup>+</sup> ion diffusion, which increases the conductivity Spiro-OMeTAD layer and built-in potential within cells. The synergetic effects improve charge injection at both interfaces device performance.
Abstract To electrically control magnetic properties of material is promising toward spintronic applications, where the investigation carrier doping effects on antiferromagnetic (AFM) materials remains challenging due to their zero net magnetization. In this work, authors find electron dependent variation orders a 2D AFM insulator NiPS 3 , concentration tuned by intercalating various organic cations into van der Waals gaps without introduction defects and impurity phases. The doped shows an...
Flat bands (FBs), presenting a strongly interacting quantum system, have drawn increasing interest recently. However, experimental growth and synthesis of FB materials been challenging remained elusive for the ideal form monolayer where arises from destructive interference as predicted in 2D lattice models. Here, we report surface self-assembled hydrogen-bond (H-bond) organic frameworks (HOFs) 1,3,5-tris(4-hydroxyphenyl)benzene (THPB) on Au(111) substrate observation FB. High-resolution...
The surface properties of metals and metal oxides can be modified by adding a single layer organic molecules. A most popular route for depositing such molecular is via the formation self-assembled monolayers (SAMs). molecules that form SAMs have functionality which binds to adsorption self-regulated terminate at exactly one layer. very first example, has become widely studied system, on surfaces consists chemisorbed alkylthiolate gold. Despite simplicity in preparation alkanethiol seemingly...
Interface enhanced superconductivity at two dimensional limit has become one of most intriguing research directions in condensed matter physics. Here, we report the superconducting properties ultra-thin FeSe films with thickness unit cell (1-UC) grown on conductive and insulating SrTiO3 (STO) substrates. For 1-UC STO substrate (Nb-STO), magnetization versus temperature (M-T) measurement shows a drop crossover around 85 K. substrate, systematic transport measurements were carried out sheet...
Alkali-metal (potassium) adsorption on FeSe thin films with thickness from two unit cells (UC) to 4-UC SrTiO3 grown by molecular beam epitaxy is investigated a low-temperature scanning tunneling microscope. At appropriate potassium coverage (0.2-0.3 monolayer), the spectra of all exhibit superconducting-like gap larger than 11 meV (five times value bulk FeSe), and distinct features characteristic phonon modes at 21 meV. The results reveal critical role interface enhanced electron-phonon...
Significance The doping-induced insulator-to-superconductor transition has been widely observed in cuprates, which provides important information for understanding the superconductivity mechanism. However, iron-based superconductors, no evidence of insulator–superconductor (or crossover) reported so far. In this paper, to our knowledge, we report first electronic an crossover single-layer FeSe film grown on a SrTiO 3 substrate, exhibits similar behaviors that cuprate superconductors. may be...
Polymorphic structures of transition metal dichalcogenides (TMDs) host exotic electronic states, like charge density wave and superconductivity. However, the number these is limited by crystal symmetries, which poses a challenge to achieving tailored lattices properties both theoretically experimentally. Here, we report coloring-triangle (CT) latticed MoTe2 monolayer, termed CT-MoTe2, constructed controllably introducing uniform ordered mirror-twin-boundaries into pristine monolayer via...
A single unit cell FeTe${}_{1-x}$Se${}_{x}$ film consisting of a flat square Fe layer sandwiched between two Se/Te monolayers shows fully gapped tunneling spectrum with superconducting gaps up to ~16.5 meV, nearly ten times the gap value an optimally doped bulk crystal. Compared ${T}_{c}$~14.5 K FeTe${}_{0.6}$Se${}_{0.4}$, meV could correspond transition temperature higher than boiling liquid-nitrogen (77 K). Initial $e\phantom{\rule{0}{0ex}}x$...
Interface-enhanced high-temperature superconductivity in one unit-cell (UC) FeSe films on SrTiO3(001) (STO) substrate has recently attracted much attention condensed matter physics and material science. By combined in-situ scanning tunneling microscopy/spectroscopy (STM/STS) ex-situ transmission electron microscopy (STEM) studies, we report atomically resolved structure including both lattice constants actual atomic positions of the FeSe/STO interface under non-superconducting...
Abstract The WSe 2 monolayer in 1T’ phase is reported to be a large‐gap quantum spin Hall insulator, but thermodynamically metastable and so far the fabricated samples have always been mixed of 2H, which has become bottleneck for further exploration potential applications nontrivial topological properties. Based on first‐principle calculations this work, it found that could more stable than 2H with enhanced interface interactions. Inspired by discovery, SrTiO 3 (100) chosen as substrate...
Selective C(sp3) -H activation is of fundamental importance in processing alkane feedstocks to produce high-value-added chemical products. By virtue an on-surface synthesis strategy, we report selective cascade dehydrogenation n-alkane molecules under surface constraints, which yields monodispersed all-trans conjugated polyenes with unprecedented length controllability. We are also able demonstrate the generality this concept for alkyl-substituted programmable lengths and diverse...
A charge density wave (CDW) is a collective quantum phenomenon in metals and features wavelike modulation of the conduction electron density. microscopic understanding experimental control this many-body electronic state atomically thin materials remain hot topics physics. By means material engineering, we realized dimensionality Zr intercalation induced semiconductor-metal phase transition 1T-ZrX2 (X = Se, Te) ultrathin films, accompanied by commensurate 2 × CDW order. Furthermore, observed...
Two-dimensional topological insulators hosting the quantum spin Hall effect have application potential in dissipationless electronics. To observe at elevated temperatures, a wide band gap is indispensable to efficiently suppress bulk conduction. Yet, most candidate materials exhibit narrow or even negative gaps. Here, via elegant control of van der Waals epitaxy, we successfully grown monolayer ZrTe5 on bilayer graphene/SiC substrate. The epitaxial crystalizes two allotrope isomers with...
One-dimensional (1D) metallic mirror-twin boundaries (MTBs) in monolayer transition-metal dichalcogenides exhibit a periodic charge modulation and provide an ideal platform for exploring collective electron behavior the confined system. The underlying mechanism of how electrons travel 1D structures remain controversial. Here, first time, we observed atomic-scale distribution within one period MTB MoTe2 by using scanning tunneling microscopy/spectroscopy. coexisting apparent lattice...
Abstract The n‐i‐p type perovskite solar cells suffer unpredictable catastrophic failure under operation, which is a barrier for their commercialization. fluorescence enhancement at Ag electrode edge and performance recovery after cutting the off prove that shunting position mainly located of device. Surface morphology elemental analyses corrosion diffusion + ions on aged cells. Moreover, much condensed larger clusters are formed MoO 3 layer. Such contrast also observed while comparing...
Transition metal oxides are promising candidates in the field of thermoelectricity, which can convert heat and electricity into each other realize efficient utilization waste energy. For figure merit ZT = S2σT/(κe + κl), a lower thermal conductivity is desired for an enhanced ZT, cation doping appropriate way to regulate transport properties. However, because S, σ, κe strongly coupled with other, one parameter modification generate compensation others, making regulation more difficult. In...