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1.
J Am Chem Soc ; 146(12): 7885-7904, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38483827

RESUMO

Integrated electronics and optoelectronics based on organic semiconductors have attracted considerable interest in displays, photovoltaics, and biosensing owing to their designable electronic properties, solution processability, and flexibility. Miniaturization and integration of devices are growing trends in molecular electronics and optoelectronics for practical applications, which requires large-scale and versatile assembly strategies for patterning organic micro/nano-structures with simultaneously long-range order, pure orientation, and high resolution. Although various integration methods have been developed in past decades, molecular electronics still needs a versatile platform to avoid defects and disorders due to weak intermolecular interactions in organic materials. In this perspective, a roadmap of organic integration technologies in recent three decades is provided to review the history of molecular electronics. First, we highlight the importance of long-range-ordered molecular packing for achieving exotic electronic and photophysical properties. Second, we classify the strategies for large-scale integration of molecular electronics through the control of nucleation and crystallographic orientation, and evaluate them based on factors of resolution, crystallinity, orientation, scalability, and versatility. Third, we discuss the multifunctional devices and integrated circuits based on organic field-effect transistors (OFETs) and photodetectors. Finally, we explore future research directions and outlines the need for further development of molecular electronics, including assembly of doped organic semiconductors and heterostructures, biological interfaces in molecular electronics and integrated organic logics based on complementary FETs.

2.
Small ; 20(27): e2308616, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38308333

RESUMO

Layered metal-halide perovskites, a category of self-assembled quantum wells, are of paramount importance in emerging photonic sources, such as lasers and light-emitting diodes (LEDs). Despite high trap density in two-dimensional (2D) perovskites, efficient non-radiative energy funneling from wide- to narrow-bandgap components, sustained by the Förster resonance energy transfer (FRET) mechanism, contributes to efficient luminescence by light or electrical injection. Herein, it is demonstrated that bandgap extension of layered perovskites to the blue-emitting regime will cause sluggish and inefficient FRET, stemming from the tiny spectral overlap between different phases. Motivated by the importance of blue LEDs and inefficient energy transfer in materials with phase polydispersity, wide-bandgap quasi-2D perovskites with narrow phase distribution, improved crystallinity, and the pure crystal orientation perpendicular to the charge transport layer are developed. Based on this emitter, high-performance blue perovskite LEDs with improved electroluminescence (EL) external quantum efficiency (EQE) of 7.9% at 478 nm, a narrow full width at half-maximum (FWHM) of 22 nm and a more stable EL spectra are achieved. These results provide an important insight into spectrally stable and efficient blue emitters and EL devices based on perovskites.

3.
Acc Chem Res ; 57(2): 222-233, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38170611

RESUMO

ConspectusSelf-assembly, a spontaneous process that organizes disordered constituents into ordered structures, has revolutionized our fundamental understanding of living matter, nanotechnology, and molecular science. From the perspective of nanomaterials, self-assembly serves as a bottom-up method for creating long-range-ordered materials. This is accomplished by tailoring the geometry, chemistry, and interactions of the components, thereby facilitating the efficient fabrication of high-quality materials and high-performance functional devices. Over the past few decades, we have seen controllable organization and diverse phases in self-assembled materials, such as organic crystals, biomolecular structures, and colloidal nanoparticle supercrystals. However, most self-assembled ordered materials and their assembly mechanisms are derived from constituents in a liquid bulk medium, where the effects of boundaries and interfaces are negligible. In the context of nanostructure patterning, self-assembly occurs in confined spaces, with feature sizes ranging from a few to hundreds of nanometers. In such settings, ubiquitous boundaries and interfaces can trap the system in a kinetically favored but metastable state, devoid of long-range order. This makes it extremely difficult to achieve ordered structures in micro/nano-patterning techniques that rely on sessile microdroplets, such as inkjet printing, dip-pen lithography, and contact printing.In stark contrast to sessile droplets, capillary bridges─formed by liquids confined between two solid surfaces─provide unique opportunities for understanding the long-range-ordered self-assembly of crystalline materials under spatial confinement. Because capillary bridges are stabilized by Laplace pressure, which is inversely proportional to the feature size, the confinement and manipulation of solutions or suspensions of functional materials at the nanoscale become accessible through the rational design of surface chemistry and geometry. Although global thermodynamic equilibrium is unattainable in evaporative systems, ordered nucleation and packing of constituent components can be locally realized at the contact line of capillary bridges. This enables the unprecedented fabrication of long-range-ordered micro/nanostructures with deterministic patterns.In this Account, we review the advancements in long-range-ordered self-assembly of crystalline micro/nanostructures under confinement. First, we briefly introduce crystalline materials characterized by strong intramolecular interactions and relatively weak intermolecular forces, analyzing both the opportunities and challenges inherent to self-assembled nanomaterials. Next, we delve into the construction and manipulation of confined liquids, focusing especially on capillary bridges controlled by engineered chemistry and geometry to regulate Laplace pressure. Through this approach, we have achieved capillary bridges with thicknesses on the order of a few nanometers and wafer-scale homogeneity, facilitating the self-assembly of ordered structures. Supported by factors such as local free-volume entropy, electrostatic interactions, curvilinear geometry, directional microfluidics, and nanoconfinement, we have achieved long-range-ordered, deterministic patterning of organic semiconductors, metal-halide perovskites, and colloidal nanocrystal superlattices using this capillary-bridge platform. These long-range microstructures serve as a bridge between nanomaterials and integrated devices, enabling emergent functionalities like intrinsic stretchability, giant photoconductivity, propagating and interacting exciton polaritons, and spin-valley-locked lasing, which are otherwise unattainable in disordered materials. Finally, we discuss potential directions for both the fundamental understanding and practical applications of confined self-assembly.

4.
Water Res ; 249: 121001, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38113602

RESUMO

Microplastics can easily enter the aquatic environment and be transported between water bodies. The terminal settling velocity of microplastics, which affects their transport and distribution in the aquatic environment, is mainly influenced by their size, density, and shape. Due to the difficulty in accurately predicting the terminal settling velocity of microplastics with various shapes, this study focuses on establishing high-performance prediction models and understanding the importance and effect of each feature parameter using machine learning. Based on the number of principal dimensions, the shapes of microplastics are classified into fiber, film, and fragment, and their thresholds are identified. The microplastics of different shape categories have different optimal shape parameters for predicting the terminal settling velocity: Corey shape factor, flatness, elongation, and sphericity for the fragment, film, fiber, and mixed-shape MPs, respectively. By including the dimensionless diameter, relative density and optimal shape parameter in the input parameter combination, the machine learning models can well predict the terminal settling velocity for the microplastics of different shape categories and mixed-shape with R2 > 0.867, achieving significantly higher performance than the existing theoretical and regression models. The interpretable analysis of machine learning reveals the highest importance of the microplastic size and its marginal effect when the dimensionless diameter D* = dn(g/v2)1/3 > 80, where dn is the equivalent diameter, g is the gravitational acceleration, and ν is the fluid kinematic viscosity. The effect of shape is weak for small microplastics and becomes significant when D* exceeds 65.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos , Poluentes Químicos da Água/análise , Monitoramento Ambiental
5.
Nat Commun ; 14(1): 5392, 2023 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-37666847

RESUMO

Tuning the composition of perovskites to approach the ideal bandgap raises the single-junction Shockley-Queisser efficiency limit of solar cells. The rapid development of narrow-bandgap formamidinium lead triiodide-based perovskites has brought perovskite single-junction solar cell efficiencies up to 26.1%. However, such compositional engineering route has reached the limit of the Goldschmidt tolerance factor. Here, we experimentally demonstrate a resonant perovskite solar cell that produces giant light absorption at the perovskite band edge with tiny absorption coefficients. We design multiple guide-mode resonances by momentum matching of waveguided modes and free-space light via Brillouin-zone folding, thus achieving an 18-nm band edge extension and 1.5 mA/cm2 improvement of the current. The external quantum efficiency spectrum reaches a plateau of above 93% across the spectral range of ~500 to 800 nm. This resonant nanophotonics strategy translates to a maximum EQE-integrated current of 26.0 mA/cm2 which is comparable to that of the champion single-crystal perovskite solar cell with a thickness of ~20 µm. Our findings break the ray-optics limit and open a new door to improve the efficiency of single-junction perovskite solar cells further when compositional engineering or other carrier managements are close to their limits.

6.
Natl Sci Rev ; 10(1): nwac096, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37601295

RESUMO

Quantized vortices appearing in topological excitations of quantum phase transition play a pivotal role in strongly correlated physics involving the underlying confluence of superfluids, Bose-Einstein condensates and superconductors. Exciton polaritons as bosonic quasiparticles have enabled studies of non-equilibrium quantum gases and superfluidity. Exciton-polariton condensates in artificial lattices intuitively emulate energy-band structures and quantum many-body effects of condensed matter, underpinning constructing vortex lattices and controlling quantum fluidic circuits. Here, we harness exciton-polariton quantum fluids of light in a frustrated kagome lattice based on robust metal-halide perovskite microcavities, to demonstrate vortex lasing arrays and modulate their configurations at room temperature. Tomographic energy-momentum spectra unambiguously reveal massless Dirac bands and quenched kinetic-energy flat bands coexisting in kagome lattices, where polariton condensates exhibit prototypical honeycomb and kagome spatial patterns. Spatial coherence investigations illustrate two types of phase textures of polariton condensates carrying ordered quantized-vortex arrays and π-phase shifts, which could be selected when needed using lasing emission energy. Our findings offer a promising platform on which it is possible to study quantum-fluid correlations in complex polaritonic lattices and highlight feasible applications of structured light.

8.
J Am Chem Soc ; 145(16): 8908-8916, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37057869

RESUMO

Chiral perovskites have attracted considerable attention owing to their potential applications in spintronic- and polarization-based optoelectronic devices. However, the structural chirality/asymmetry transfer mechanism between chiral organic ammoniums and achiral inorganic frameworks is still equivocal, especially under extreme conditions, as the systematic structural differences between chiral and achiral perovskites have been rarely explored. Herein, we successfully synthesized a pair of new enantiomeric chiral perovskite (S/R-3PYEA)PbI4 (3PYEA2+ = C5NH5C2H4NH32+) and an achiral perovskite (rac-3PYEA)PbI4. Hydrostatic pressure was used, for the first time, to systematically investigate the differences in the structural evolution and optical behavior between (S/R-3PYEA)PbI4 and (rac-3PYEA)PbI4. At approximately 7.0 GPa, (S/R-3PYEA)PbI4 exhibits a chirality-dependent structural transformation with a bandgap "red jump" and dramatic piezochromism from translucent red to opaque black. Upon further compression, a previously unreported chirality-induced negative linear compressibility (NLC) is achieved in (S/R-3PYEA)PbI4. High-pressure structural characterizations and first-principles calculations demonstrate that pressure-driven homodirectional tilting of homochiral ammonium cations strengthens the interactions between S/R-3PYEA2+ and Pb-I frameworks, inducing the formation of new asymmetric hydrogen bonds N-H···I-Pb in (S/R-3PYEA)PbI4. The enhanced asymmetric H-bonding interactions further break the symmetry of (S/R-3PYEA)PbI4 and trigger a greater degree of in-plane and out-of-plane distortion of [PbI6]4- octahedra, which are responsible for chirality-dependent structural phase transition and NLC, respectively. Nevertheless, the balanced H-bonds incurred by equal proportions of S-3PYEA2+ and R-3PYEA2+ counteract the tilting force, leading to the absence of chirality-dependent structural transition, spectral "red jump", and NLC in (rac-3PYEA)PbI4.

9.
Nat Mater ; 22(9): 1065-1070, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37081172

RESUMO

Circularly polarized light sources with free-space directional emission play a key role in chiroptics1, spintronics2, valleytronics3 and asymmetric photocatalysis4. However, conventional approaches fail to simultaneously realize pure circular polarization, high directionality and large emission angles in a compact emitter. Metal-halide perovskite semiconductors are promising light emitters5-8, but the absence of an intrinsic spin-locking mechanism results in poor emission chirality. Further, device integration has undermined the efficiency and directionality of perovskite chiral emitters. Here we realize compact spin-valley-locked perovskite emitting metasurfaces where spin-dependent geometric phases are imparted into bound states in the continuum via Brillouin zone folding, and thus, photons with different spins are selectively addressed to opposite valleys. Employing this approach, chiral purity of 0.91 and emission angle of 41.0° are simultaneously achieved, with a beam divergence angle of 1.6°. With this approach, we envisage the realization of chiral light-emitting diodes, as well as the on-chip generation of entangled photon pairs.

10.
Adv Mater ; 35(19): e2210594, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36859570

RESUMO

Orientational growth of single-crystalline structures is pivotal in the semiconductor industry, which is achievable by epitaxy for producing thin films, heterostructures, quantum wells, and superlattices. Beyond silicon and III-V semiconductors, solution-processible semiconductors, such as metal-halide perovskites, are emerging for scalable and cost-effective manufacture of optoelectronic devices, whereas the polycrystalline nature of fabricated structures restricts their application toward integrated devices. Here, electrostatic epitaxy, a process sustained by strong electrostatic interactions between self-assembled surfactants (octanoate anions) and Pb2+ , is developed to realize orientational growth of single-crystalline CsPbBr3 microwires. Strong electrostatic interactions localized at the air-liquid interface not only support preferential nucleation for single crystallinity, but also select the crystal facet with the highest Pb2+ areal density for pure crystallographic orientation. Due to the epitaxy at the air-liquid interface, direct growth of oriented single-crystalline microwires onto different substrates without the processes of lift-off and transfer is realized. Photonic lasing emission, waveguide coupling, and on-chip propagation of coherent light are demonstrated based on these single-crystalline microwires. These findings open an avenue for on-chip integration of single-crystalline materials.

11.
J Biomater Appl ; 37(9): 1626-1631, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36847197

RESUMO

The purpose of this study is to explore the effect of using 3D printed pelvic prosthesis to reconstruct bone defect after pelvic tumor resection. From June 2018 to October 2021, a total of 10 patients with pelvic tumors underwent pelvic tumor resection and 3D printed customized hemipelvic prosthesis reconstruction in our hospital. Enneking pelvic surgery subdivision method was used to determine the degree of tumor invasion and the site of prosthesis reconstruction. 2 cases in Zone I, 2 cases in Zone II, 3 cases in Zone I + II, 2 cases in Zone II + III and 1 case in Zone I + II + III. Patients had preoperative VAS scores of 6.5 ± 1.3, postoperative VAS scores of 2.2 ± 0.9, preoperative MSTS-93 scores of 9.4 ± 5.3 and postoperative 19.4 ± 5.9(p < 0.05), all patients had improvement in pain after surgery; Postoperative complications included joint dislocation in 2 cases, myasthenia caused by Guillain-Barre syndrome in 1 case, delayed wound healing in 3 cases and wound infection in 2 cases. Postoperative wound-related complications and dislocations were associated with the extent of the tumor. Patients with tumor invasion of the iliopsoas and gluteus medius muscles had higher complication rates and worse postoperative MSTS scores (p < 0.05). The patients were followed up for 8 ∼ 28 months. During the follow-up period, 1 case recurred, 4 cases metastasized and 1 case died. All pelvic CTs reviewed 3-6 months after surgery showed good alignment between the 3D printed prosthesis and the bone contact, and tomography showed the growth of trabecular structures into the bone. Overall pain scores decreased and functional scores improved in patients after 3D printed prosthesis replacement for pelvic tumor resection. Long-term bone ingrowth could be seen on the prosthesis-bone contact surface with good stability.


Assuntos
Neoplasias Ósseas , Neoplasias Pélvicas , Humanos , Neoplasias Pélvicas/patologia , Neoplasias Pélvicas/cirurgia , Neoplasias Ósseas/cirurgia , Neoplasias Ósseas/patologia , Implantação de Prótese , Complicações Pós-Operatórias , Impressão Tridimensional , Dor/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
12.
Comput Math Methods Med ; 2022: 7214904, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36276991

RESUMO

Objective: Synovial sarcoma is a rare malignant tumor. The role of apatinib in synovial sarcoma remains unclear. In this study, we aimed to determine the biological functions and the potential molecular mechanism of action of apatinib in synovial sarcoma. Methods: SW982 cells were stimulated with apatinib. The relative expression of the genes was determined by performing qPCR. Protein levels were evaluated by western blot and immunohistochemistry assays. Proliferation, apoptosis, migration, and invasion of SW982 cells were determined by the CCK-8 assay, clone formation assay, flow cytometry, wound healing, and the transwell assay, respectively. Additionally, SW982 cells were injected into mice to induce synovial sarcoma. Results: Apatinib decreased the proliferation, migration, and invasion but increased the apoptosis of SW982 cells. Apatinib repressed tumor growth in vivo and elevated miR-34a-5p in SW982 cells. The inhibition of miR-34a-5p repressed the reduction of proliferation, migration, and invasion and also the elevation of apoptosis in apatinib-treated SW982 cells. The luciferase activity decreased after cotransfection of the miR-34a-5p mimic and the wild-type HOXA13 vector. Additionally, an increase in miR-34a-5p repressed the levels of HOXA13 mRNA and protein. Moreover, HOXA13 reversed these patterns caused by the inhibition of miR-34a-5p in apatinib-treated SW982 cells. Conclusion: Apatinib elevated miR-34a-5p and reduced HOXA13, leading to a significant decrease in proliferation, migration, and invasion, along with an enhancement of apoptosis in SW982 cells. Apatinib suppressed tumorigenesis and tumor growth in SW982 cells in vivo.


Assuntos
MicroRNAs , Sarcoma Sinovial , Camundongos , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Proliferação de Células , Sarcoma Sinovial/tratamento farmacológico , Sarcoma Sinovial/genética , Linhagem Celular Tumoral , Apoptose , RNA Mensageiro , Luciferases , Movimento Celular/genética
13.
Nano Lett ; 22(20): 8274-8280, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36197087

RESUMO

Colloidal nanocrystals that are capable of mass production with wet chemical synthesis have long been proposed as color-tunable, scalable quantum emitters for information processing and communication. However, they constantly suffer from spectral diffusion due to being exposed to a noisy electrostatic environment. Herein we demonstrate a cavity-photon interface (CPI) which effectively suppresses the temperature-activated spectral diffusion (SD) of a single perovskite nanoplatelet (NPL) up to 40 K. The spectrally stabilized single-photon emission is achieved at a specific emission direction corresponding to an inhibited dipole moment of the NPL as the result of the Fano coupling between the two photon dissipation channels of the NPL. Our results shed light on the nature of the SD of perovskite nanocrystals and offer a general cavity quantum electrodynamic scheme that controls the brightness and spectral dynamics of a single-photon emitter.

14.
ACS Appl Mater Interfaces ; 14(28): 32761-32770, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35816371

RESUMO

Patterning organic semiconductors directly on Au electrodes possesses the advantages of eliminating metal atomic penetration effect, compatibility with fine lithography processes, and feasibility of work function modification on electrodes, and it is therefore of value in the commercial manufacturability application of optoelectronic devices with low cost, large scale, and high efficiency. Solution processing, is relatively inexpensive and is scalable to large areas. Nonetheless, conventional solution processing approaches have trade-offs among controllable morphology, regular alignment, precise position, and ordered molecular packing arising from the uncontrollable dewetting kinetics. Here, one-step patterning of 1D polymer nanowire arrays directly on Au source-drain electrodes with precise position, controlled orientation, regulated distribution, and tunable width size were realized by employing a capillary-bridge manipulation method to guide the processes of liquid dewetting and nanowire assembly. Organic field-effect transistors (OFETs) with mobility of 10.1 cm2 V-1 s-1 and on/off current ratio of 1.9 × 104 were fabricated. Moreover, we verified generality of our method by patterning different solution-processable optoelectronic materials, including small molecules, quantum dot (QD) nanoparticles, and metal-halide perovskites, into ordered structures directly on the target substrate. The work provides a novel insight into efficient manufacturing the regular aligned and precisely positioned 1D organic semiconductors directly on the channel region of prefabricated Au electrodes in one step and facilitates their applications in high-performance electronic devices.

15.
Adv Mater ; 34(28): e2202119, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35522854

RESUMO

Long-range-ordered structures of nanoparticles with controllable orientation have advantages in applications toward sensors, photoelectric conversion, and field-effect transistors. The assembly process of nanorods in colloidal systems undergoes a nonequilibrium process from dispersion to aggregation. A variety of assembly methods such as solvent volatilization, electromagnetic field induction, and photoinduction are restricted to suppress local perturbations during the nonequilibrium concentration of nanoparticles, which are adverse to controlling the orientation and order of assembled structures. Here, a confined assembly method is reported by locally controlling free-volume entropy in nonequilibrium fluids to fabricate microstructure arrays based on colloidal nanorods with controllable orientation and long-range order. The unique fluid dynamics of the liquid bridge is utilized to form a local region, where the free volume entropy reduction triggers assembly near the three-phase contact line (TPCL), allowing nanorods to assemble in 2D closest packing parallel to the TPCL for the maximum Gibbs free energy reduction. By manipulating the orientation of liquid flow, microstructures are assembled with programmable geometry, which sustains polarized photoluminescence and polarization-dependent photodetection. This confined assembly method opens up perspectives on assemblies of nanomaterials with controllable orientation and long-range order as a platform for multifunctional integrated devices.

16.
Adv Mater ; 34(24): e2110695, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35411618

RESUMO

Colloidal quantum dots (CQDs) are promising for photonic applications toward lasers, waveguides, and photodetectors. However, integration of high-quality photonic elements into multifunctional devices is still restricted by optical losses stemming from the accumulation of defects and disorder in the solution process. Herein, a platform with a directional Laplace pressure is created for eliminating undesired pinning of liquid fronts in the solution process and boosting ordered assembly of CQDs into designable micro-/nanostructures. The versatility and robustness of this method are demonstrated by deterministic patterning of CQDs with different components and photoluminescence spectra onto various substrates. On the basis of this platform, microring lasers with tunable emission modes, low-loss waveguides, and their coupled structures have been reached for direct on-chip generation and propagation of coherent light. A proof-of-concept demonstration of integrated circuits is also conducted by combining microcavity lasers with waveguides for encoding photonic outputs into information bits.

17.
Nat Nanotechnol ; 17(4): 396-402, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35288672

RESUMO

Parametric nonlinear optical processes are at the heart of nonlinear optics underpinning the central role in the generation of entangled photons as well as the realization of coherent optical sources. Exciton-polaritons are capable to sustain parametric scattering at extremely low threshold, offering a readily accessible platform to study bosonic fluids. Recently, two-dimensional transition-metal dichalcogenides (TMDs) have attracted great attention in strong light-matter interactions due to robust excitonic transitions and unique spin-valley degrees of freedom. However, further progress is hindered by the lack of realizations of strong nonlinear effects in TMD polaritons. Here, we demonstrate a realization of nonlinear optical parametric polaritons in a WS2 monolayer microcavity pumped at the inflection point and triggered in the ground state. We observed the formation of a phase-matched idler state and nonlinear amplification that preserves the valley population and survives up to room temperature. Our results open a new door towards the realization of the future for all-optical valley polariton nonlinear devices.

18.
Adv Mater ; 34(11): e2108279, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35023586

RESUMO

Large-scale assembly of organic micro/nanocrystals into well-defined patterns with programmable structures is essential for applications such as information encryption at both high data density and high security level. Here, a magnetic-field-assisted approach that produces programmable assemblies of organic microcrystals with various shapes and orientations, using the magnetic domains of the underlying ferromagnetic metal microarrays as the printing templates, is developed. The diamagnetic microcrystals tend to aggregate in the regions of minimal field strength, and thus their assembly behavior is precisely controlled by the local field distribution on top of magnetic domains on substrate. The dynamic assembly process of microcrystal assemblies can be programmed upon the sequence of applied field, and their shape changes are ≈100% reproducible on a large scale (>20 000 sites over 1 cm2 ). These features of magnetically programmable assemblies are ideally suited for information encryption, for which the encryption-decryption-erasing of multilevel information from a QR-code pattern based on the microcrystal assemblies under magnetic field is demonstrated.

19.
ACS Appl Mater Interfaces ; 14(1): 1601-1608, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34978173

RESUMO

Metal-halide layered perovskites, self-assembled quantum wells with alternating insulating interlayer organic cations, and conductive perovskite layers boost the incorporation of multiple functionalities into a single-phase material. Optoelectronic performances in layered perovskites are more sensitive to crystallinity than their 3D counterparts due to the traps and insulating barriers introduced by interlayer cations. Here, we combine the capillary-bridge lithography method for the fabrication of single-crystalline nanowire arrays with strongly interacted layered perovskites for the enhancement of crystallinity and crystallographic orientation purity. Due to regulated nucleation and growth of layered perovskites in capillary bridges and the sulfur-sulfur interaction between interlayer cations, nanowires with pure (101) orientation are realized for underpinning insulating crystal interiors and photoconductive layer edges. Based on these nanowires, ultrasensitive photodetectors are reached with an ultralow dark current of below 10-12 A, an average responsivity of 7.3 × 103 A W-1, an average specific detectivity of 3.9 × 1015 Jones, and a 3 dB bandwidth of 10.3 kHz.

20.
Adv Mater ; 34(9): e2106857, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34908188

RESUMO

On-chip integration of solution-processable materials imposes stringent and simultaneous requirements of controlled nucleation and growth, tunable geometry and dimensions, and long-range-ordered assembly, which is challenging in solution process far from thermodynamic equilibrium. Superwetting interfaces, underpinned by programmable surface chemistry and topography, are promising for steering transport, dewetting, and microfluid dynamics of liquids, thus opening a new paradigm for micro-/nanostructure assembly in solution process. Herein, assembly methods on the basis of superwetting interfaces are reviewed for constructing long-range-ordered micro-/nanostructures. Confined capillary liquids, including capillary bridges and capillary corner menisci realized by controlling local wettability and surface topography, are highlighted for simultaneously attained deterministic patterning and long-range order. The versatility and robustness of confined capillary liquids are discussed with assembly of single-crystalline micro-/nanostructures of organic semiconductors, metal-halide perovskites, and colloidal-nanoparticle superlattices, which lead to enhanced device performances and exotic functionalities. Finally, a perspective for promising directions in this realm is provided.

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