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1.
J Colloid Interface Sci ; 675: 302-312, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38972118

RESUMEN

Electrocatalytic water splitting produces green and pollution-free hydrogen as a clean energy carrier, which can effectively alleviate energy crisis. In this paper, bimetallic and selenium doped cobalt molybdate (Se-CoMoO4) nanosheets with rough surface are resoundingly prepared. The multihole Se-CoMoO4 nanosheets display ultrathin and rectangular architecture with the dimensions of âˆ¼ 3.5 µm and 700 nm for length and width, respectively. The Se-CoMoO4 electrocatalyst shows remarkable water electrolysis activity and stability. The overpotentials of oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) are 270 and 63.3 mV at 10 mA cm-2, along with low Tafel slopes of 51.6 and 62.0 mV dec-1. Furthermore, the Se-CoMoO4 couple electrolyzer merely requires a cell voltage of 1.48 V to achieve 10 mA cm-2 current density and presents no apparent attenuation for 30 h. This investigation declares that the hybridization of transition bimetallic oxide with nonmetallic adulteration can afford a tactic for the preparation of bifunctional non-precious metal-based electrocatalysts.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 320: 124594, 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-38875928

RESUMEN

A new ratiometric fluorescent sensor (LP) based on bicarboxaminoquinoline was designed and synthesized for sequentially recognizing Zn2+ and PPi. In aqueous solution, LP exhibited the ratiometric fluorescence response towards Zn2+, along with the about 4-folds enhancement of fluorescence quantum yield. Subsequently, the LP-Zn2+ complex displayed the fluorescence recovery upon adding PPi through the displacement strategy. And the LODs of LP and its Zn2+ complex for sensing Zn2+ and PPi were found to be 15 nM and 5.5 nM, respectively. Notably, the reversibility of LP for sequentially sensing Zn2+ and PPi had been employed to construct the INHIBIT logic gate. Moreover, LP and its Zn2+ complex had been successfully utilized for the detection of Zn2+ and PPi in two real water samples and cells imaging.

3.
Adv Sci (Weinh) ; : e2401716, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38840455

RESUMEN

The demand for miniaturized and integrated multifunctional devices drives the progression of high-performance infrared photodetectors for diverse applications, including remote sensing, air defense, and communications, among others. Nonetheless, infrared photodetectors that rely solely on single low-dimensional materials often face challenges due to the limited absorption cross-section and suboptimal carrier mobility, which can impair sensitivity and prolong response times. Here, through experimental validation is demonstrated, precise control over energy band alignment in a type-II van der Waals heterojunction, comprising vertically stacked 2D Ta2NiSe5 and the topological insulator Bi2Se3, where the configuration enables polarization-sensitive, wide-spectral-range photodetection. Experimental evaluations at room temperature reveal that the device exhibits a self-powered responsivity of 0.48 A·W-1, a specific directivity of 3.8 × 1011 cm·Hz1/2·W-1, a response time of 151 µs, and a polarization ratio of 2.83. The stable and rapid photoresponse of the device underpins the utility in infrared-coded communication and dual-channel imaging, showing the substantial potential of the detector. These findings articulate a systematic approach to developing miniaturized, multifunctional room-temperature infrared detectors with superior performance metrics and enhanced capabilities for multi-information acquisition.

4.
Ultrasound Q ; 40(3)2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38889436

RESUMEN

ABSTRACT: We aimed to develop and validate a nomogram based on conventional ultrasound (CUS) radiomics model to differentiate radial scar (RS) from invasive ductal carcinoma (IDC) of the breast. In total, 208 patients with histopathologically diagnosed RS or IDC of the breast were enrolled. They were randomly divided in a 7:3 ratio into a training cohort (n = 145) and a validation cohort (n = 63). Overall, 1316 radiomics features were extracted from CUS images. Then a radiomics score was constructed by filtering unstable features and using the maximum relevance minimum redundancy algorithm and the least absolute shrinkage and selection operator logistic regression algorithm. Two models were developed using data from the training cohort: one using clinical and CUS characteristics (Clin + CUS model) and one using clinical information, CUS characteristics, and the radiomics score (radiomics model). The usefulness of nomogram was assessed based on their differentiating ability and clinical utility. Nine features from CUS images were used to build the radiomics score. The radiomics nomogram showed a favorable predictive value for differentiating RS from IDC, with areas under the curve of 0.953 and 0.922 for the training and validation cohorts, respectively. Decision curve analysis indicated that this model outperformed the Clin + CUS model and the radiomics score in terms of clinical usefulness. The results of this study may provide a novel method for noninvasively distinguish RS from IDC.


Asunto(s)
Neoplasias de la Mama , Mama , Carcinoma Ductal de Mama , Nomogramas , Ultrasonografía Mamaria , Humanos , Femenino , Neoplasias de la Mama/diagnóstico por imagen , Persona de Mediana Edad , Diagnóstico Diferencial , Ultrasonografía Mamaria/métodos , Carcinoma Ductal de Mama/diagnóstico por imagen , Adulto , Mama/diagnóstico por imagen , Cicatriz/diagnóstico por imagen , Anciano , Reproducibilidad de los Resultados , Estudios Retrospectivos , Radiómica
5.
JPRAS Open ; 41: 4-8, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38784717

RESUMEN

Onycholemmal carcinoma is characterized as a slowly progressing malignant tumor originating from the epithelium of the nail bed. A limited number of cases have been documented in the English literature. The majority of the patients included in the reports underwent amputation of the affected phalanx, and no instances of recurrence were noted during the follow-up period. A 61-year-old Chinese male presented with a persistent ulceration on the nail bed of the right great toe. Microscopic analysis indicated the presence of an epithelial tumor consisting of small keratocysts with sudden central keratinization and atypical keratinocyte nests that were devoid of a granular layer. The tumor exhibited infiltrative growth within the dermis, displaying a multilobulated pattern, but did not extend into the distal phalangeal bone. Based on these findings, the diagnosis of onycholemmal carcinoma was made for this case. All documented cases indicate that onycholemmal carcinoma is a rare malignant tumor originating from the nail bed epithelium, and its clinical progression is typically slow and non-aggressive. This case is presented to provide an analysis of the clinical and pathological features of onycholemmal carcinoma, aiming to assist in the clinical selection of treatment options.

6.
Ecotoxicol Environ Saf ; 277: 116343, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38657456

RESUMEN

Curcumin (CUR) is a compound extracted from turmeric that has a variety of functions including antioxidant and anti-inflammatory. As an estrogen-like mycotoxin, zearalenone (ZEN) not only attacks the reproductive system, but also has toxic effects on the liver. However, whether CUR can alleviate ZEN-induced liver injury remains unclear. This paper aims to investigate the protective effect of CUR against ZEN-induced liver injury in mice and explore the molecular mechanism involved. BALB/c mice were randomly divided into control (CON) group, CUR group (200 mg/kg b. w. CUR), ZEN group (40 mg/kg b. w. ZEN) and CUR+ZEN group (200 mg/kg b. w. CUR+40 mg/kg b. w. ZEN). 28 d after ZEN exposure and CUR treatment, blood and liver samples were collected for subsequent testing. The results showed that CUR reversed ZEN-induced hepatocyte swelling and necrosis in mice. It significantly reduced the serum alkaline phosphatase (ALP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in mice (p < 0.05). In addition, CUR significantly reduced hepatic ROS, malondialdehyde, hydrogen peroxide and apoptosis levels in mice (p < 0.05). Quantitative RT-PCR and Western blot results showed that CUR significantly reduced the expression of Bax and Caspase3, and reversed the increase of Nrf2, HO-1 and NQO1 expression in the liver of mice induced by ZEN (p < 0.05). In conclusion, CUR alleviated ZEN-induced liver injury in mice by scavenging ROS and inhibiting the mitochondrial apoptotic pathway.


Asunto(s)
Apoptosis , Enfermedad Hepática Inducida por Sustancias y Drogas , Curcumina , Ratones Endogámicos BALB C , Especies Reactivas de Oxígeno , Zearalenona , Animales , Zearalenona/toxicidad , Curcumina/farmacología , Apoptosis/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Ratones , Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Mitocondrias/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/patología , Hígado/metabolismo , Masculino , Estrés Oxidativo/efectos de los fármacos , Antioxidantes/farmacología
7.
Nano Lett ; 24(3): 983-992, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38206182

RESUMEN

On-chip polarization detectors have attracted extensive research interest due to their filterless and ultracompact architecture. However, their polarization-dependent photoresponses cannot be dynamically adjusted, hindering the development toward intelligence. Here, we propose dynamically reconfigurable polarimetry based on in-sensor differentiation of two self-powered photoresponses with orthogonal polarization dependences and tunable responsivities. Such a device can be electrostatically configured in an ultrahigh polarization extinction ratio (PER) mode, where the PER tends to infinity, a Stokes parameter direct sensing mode, where the photoresponse is proportional to S1 or S2 with high accuracy (RMSES1 = 1.5%, RMSES2 = 2.0%), or a background suppressing mode, where the target-background polarization contrast is singularly enhanced. Moreover, the device achieves a polarization angle sensitivity of 0.51 mA·W-1·degree-1 and a specific polarization angle detectivity of 2.8 × 105 cm·Hz1/2·W·degree-1. This scheme is demonstrated throughout the near-to-long-wavelength infrared range, and it will bring a leap for next-generation on-chip polarimeters.

8.
Nanoscale ; 15(45): 18306-18316, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37920997

RESUMEN

Two-dimensional (2D) ferroelectric semiconductors, such as α-In2Se3 with switchable spontaneous polarization and superior optoelectronic properties, exhibit large potential for functional device applications. The electric transport properties and device performance of 2D α-In2Se3 are strongly sensitive to the ferroelectric domain structures and polarization textures, but they are rarely explored at the atomic scale. Herein, by a combination of first-principles calculations and a developed domain switching theory, we report the domain nucleation kinetics and polarization-texture dependent electronic properties in α-In2Se3 ferroelectrics. Our calculated results reveal that the reversed domains characterized by armchair boundaries tend to form triangular or stripped shape. The energy barrier for propagating domain boundaries is ∼1.42 eV and can be reduced by loading external electric field, which is responsible for driving the evolution of domain structures. Moreover, the domain switching leads to notable changes in the band gap and carrier spatial distribution of α-In2Se3 monolayer, resulting in higher electric resistance of multi-polarization domain structures than that of single-polarization state. The domain structures of multilayer α-In2Se3 follow a layer-by-layer switching mechanism, which causes the transition of electronic structures from self-doped p-n junctions to type-II semiconductor homojunctions. This study not only provides an in-depth insight into the domain switching mechanisms of α-In2Se3 but also opens up the possibility to tailor their electronic and transport properties.

9.
Sci Adv ; 9(36): eadh2358, 2023 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-37682991

RESUMEN

H2BK120ub1 triggers several prominent downstream histone modification pathways and changes in chromatin structure, therefore involving it into multiple critical cellular processes including DNA transcription and DNA damage repair. Although it has been reported that H2BK120ub1 is mediated by RNF20/40 and CRL4WDR70, less is known about the underlying regulation mechanism for H2BK120ub1 by WDR70. By using a series of biochemical and cell-based studies, we find that WDR70 promotes H2BK120ub1 by interacting with RNF20/40 complex, and deposition of H2BK120ub1 and H3K79me2 in POLE3 loci is highly sensitive to POLE3 transcription. Moreover, we demonstrate that POLE3 interacts CHRAC1 to promote DNA repair by regulation on the expression of homology-directed repair proteins and KU80 recruitment and identify CHRAC1 D121Y mutation in colorectal cancer, which leads to the defect in DNA repair due to attenuated the interaction with POLE3. These findings highlight a previously unknown role for WDR70 in maintenance of genomic stability and imply POLE3 and CHRAC1 as potential therapeutic targets in cancer.


Asunto(s)
Roturas del ADN de Doble Cadena , Reparación del ADN , Mutación , Procesamiento Proteico-Postraduccional , Reparación del ADN por Recombinación
10.
Nano Lett ; 23(19): 9105-9113, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37694889

RESUMEN

Achieving perfect absorption in few-layer two-dimensional (2D) materials plays a crucial role in applications such as optoelectronics and sensing. However, the underlying mechanisms of all reported works imply a strongly inherent dependence of the central wavelength on the structural parameters. Here, we propose a structure-parameter-deviation immune method for achieving perfect absorption at any desired wavelength by harnessing the toroidal dipole-bound state in the continuum (TD BIC). We experimentally demonstrate the versatile design with a monolayer-graphene-loaded compound grating structure. Such a TD BIC built upon the TE31 mode allows for the transition from BIC to quasi-BIC without breaking the structural symmetry, enabling the stable resonance wavelength while tailoring the quality factors via variation of the gap distance. Comparison with traditional literature further reveals the superiority of our method in realizing highly robust perfect absorption, with a wavelength stability ratio of >15. Remarkably, this approach can be straightforwardly applied to other 2D materials.

11.
Sensors (Basel) ; 23(12)2023 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-37420534

RESUMEN

Studying the nonlinear photoresponse of different materials, including III-V semiconductors, two-dimensional materials and many others, is attracting burgeoning interest in the terahertz (THz) field. Especially, developing field-effect transistor (FET)-based THz detectors with preferred nonlinear plasma-wave mechanisms in terms of high sensitivity, compactness and low cost is a high priority for advancing performance imaging or communication systems in daily life. However, as THz detectors continue to shrink in size, the impact of the hot-electron effect on device performance is impossible to ignore, and the physical process of THz conversion remains elusive. To reveal the underlying microscopic mechanisms, we have implemented drift-diffusion/hydrodynamic models via a self-consistent finite-element solution to understand the dynamics of carriers at the channel and the device structure dependence. By considering the hot-electron effect and doping dependence in our model, the competitive behavior between the nonlinear rectification and hot electron-induced photothermoelectric effect is clearly presented, and it is found that the optimized source doping concentrations can be utilized to reduce the hot-electron effect on the devices. Our results not only provide guidance for further device optimization but can also be extended to other novel electronic systems for studying THz nonlinear rectification.


Asunto(s)
Semiconductores , Radiación Terahertz , Diseño de Equipo , Electrones
12.
Adv Mater ; 35(41): e2304161, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37408327

RESUMEN

The Jones matrix, with eight degrees of freedom (DoFs), provides a general mathematical framework for the multifunctional design of metasurfaces. Theoretically, the maximum eight DoFs can be further extended in the spectrum dimension to endow unique encryption capabilities. However, the topology and intrinsic spectral responses of meta-atoms constrains the continuous engineering of polarization evolution over wavelength dimension. In this work, a forward evolution strategy to quickly establish the mapping relationships between the solutions of the dispersion Jones matrix and the spectral responses of meta-atoms is reported. Based on the eigenvector transformation method, arbitrary conjugate polarization channels over the continuous-spectrum dimension are successfully reconstructed. As a proof-of-concept, a silicon metadevice is demonstrated for optical information encryption transmission. Remarkably, the arbitrary combination forms of polarization and wavelength dimension increase the information capacity (210 ), and the measured polarization contrasts of the conjugate polarization conversion are >94% in the entire wavelength range (3-4 µm). It is believed that the proposed approach will benefit secure optical and quantum information technologies.

13.
Light Sci Appl ; 12(1): 176, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37443133

RESUMEN

Filterless light-ellipticity-sensitive optoelectronic response generally has low discrimination, thus severely hindering the development of monolithic polarization detectors. Here, we achieve a breakthrough based on a configurable circular-polarization-dependent optoelectronic silent state created by the superposition of two photoresponses with enantiomerically opposite ellipticity dependences. The zero photocurrent and the significantly suppressed noise of the optoelectronic silent state singularly enhance the circular polarization extinction ratio (CPER) and the sensitivity to light ellipticity perturbation. The CPER of our device approaches infinity by the traditional definition. The newly established CPER taking noise into account is 3-4 orders of magnitude higher than those of ordinary integrated circular polarization detectors, and it remains high in an expanded wavelength range. The noise equivalent light ellipticity difference goes below 0.009° Hz-1/2 at modulation frequencies above 1000 Hz by a light power of 281 µW. This scheme brings a leap in developing monolithic ultracompact circular polarization detectors.

14.
Nat Commun ; 14(1): 3433, 2023 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-37301939

RESUMEN

High quality(Q) factor optical resonators are indispensable for many photonic devices. While very large Q-factors can be obtained theoretically in guided-mode settings, free-space implementations suffer from various limitations on the narrowest linewidth in real experiments. Here, we propose a simple strategy to enable ultrahigh-Q guided-mode resonances by introducing a patterned perturbation layer on top of a multilayer-waveguide system. We demonstrate that the associated Q-factors are inversely proportional to the perturbation squared while the resonant wavelength can be tuned through material or structural parameters. We experimentally demonstrate such high-Q resonances at telecom wavelengths by patterning a low-index layer on top of a 220 nm silicon on insulator substrate. The measurements show Q-factors up to 2.39 × 105, comparable to the largest Q-factor obtained by topological engineering, while the resonant wavelength is tuned by varying the lattice constant of the top perturbation layer. Our results hold great promise for exciting applications like sensors and filters.


Asunto(s)
Ingeniería , Fotones , Silicio , Vibración
15.
Nanotechnology ; 34(37)2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37311451

RESUMEN

Highly efficient water electrolytic agents are restricted by the lack of cheap and Earth-abundant catalysts that can manipulate at unharsh conditions and be prepared with a simple procedure. Here, hierarchically vertical and porous MoS2-CoS2heterojunction nanosheet arrays are designed and fabricated. The MoS2-CoS2nanosheets are composed of ultrasmall nanocrytallites with the dimension of ∼62 nm. This special and novel architecture presents synergistic properties to create excellent oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), where high density active sites generated by ultrasmall nanocrytallites with heterostructures, and the vertical and porous structure accelerates electrolyte transport with luxuriant channels while this hierarchically collaborative framework guarantees completely exposed active sites to electrolytes. This electrode shows low overpotentials of 295 and 103 mV at 10 mA cm-2, small Tafel slopes of 70 and 78 mV dec-1, and long stability for OER and HER, respectively. This work indicates that vertical and porous heterojunction nanosheet arrays with hierarchically ultrasmall secondary nanostructures are a promising catalyst for widespread application.


Asunto(s)
Hidrógeno , Molibdeno , Porosidad , Electrodos , Oxígeno
16.
Anal Chim Acta ; 1272: 341520, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37355337

RESUMEN

Small non-coding RNAs (sncRNAs) consisting of tRNA-derived small RNAs (tsRNAs) and miRNAs can be released by cancer cells and detected in blood, offering great potential for diagnosis of malignant tumors such as squamous cell carcinoma of the esophagus (ESCC). One of the major challenges for the clinical application of blood-based sncRNAs biomarkers is the difficulty of detection because of their small sncRNA size and low abundance. The deferentially expressed tsRNAs and miRNAs in plasma were studied with high-throughput sequencing and polymerase chain reaction in ESCC cohorts. A novel signature containing tRF-55:74-chrM.Phe-GAA, tRF-56:75-Ala-CGC-1-M4 and miR-4488 was identified with diagnostic potential. The signature was further confirmed by an attomolar-level ultrasensitive and rapid microfluidic biochip, which can achieve a multiplex, simple and low-cost detection. Our results indicated that a combination of tsRNAs and miRNAs has high diagnostic efficiency and tremendous potential to act as specific biomarkers through a reliable, highly sensitive, fast, and economic microfluidic biochip for ESCC diagnosis.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , MicroARNs , ARN Pequeño no Traducido , Humanos , Carcinoma de Células Escamosas de Esófago/diagnóstico , Carcinoma de Células Escamosas de Esófago/genética , Carcinoma de Células Escamosas de Esófago/patología , MicroARNs/genética , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , Microfluídica , Curva ROC , Biomarcadores de Tumor/genética
17.
Small ; 19(44): e2303675, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37381648

RESUMEN

Van der Waals (vdW) metal-semiconductor junctions (MSJs) exhibit huge potential to reduce the contact resistance and suppress the Fermi-level pinning (FLP) for improving the device performance, but they are limited by optional (2D) metals with a wide range of work functions. Here a new class of vdW MSJs entirely composed of atomically thin MXenes is reported. Using high-throughput first-principles calculations, highly stable 80 metals and 13 semiconductors are screened from 2256 MXene structures. The selected MXenes cover a broad range of work functions (1.8-7.4 eV) and bandgaps (0.8-3 eV), providing a versatile material platform for constructing all-MXene vdW MSJs. The contact type of 1040 all-MXene vdW MSJs based on Schottky barrier heights (SBHs) is identified. Unlike conventional 2D vdW MSJs, the formation of all-MXene vdW MSJs leads to interfacial polarization, which is responsible for the FLP and deviation of SBHs from the prediction of Schottky-Mott rule. Based on a set of screening criteria, six Schottky-barrier-free MSJs with weak FLP and high carrier tunneling probability (>50%) are identified. This work offers a new way to realize vdW contacts for the development of high-performance electronic and optoelectronic devices.

18.
Light Sci Appl ; 12(1): 105, 2023 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-37142624

RESUMEN

Objects with different shapes, materials and temperatures can emit distinct polarizations and spectral information in mid-infrared band, which provides a unique signature in the transparent window for object identification. However, the crosstalk among various polarization and wavelength channels prevents from accurate mid-infrared detections at high signal-to-noise ratio. Here, we report full-polarization metasurfaces to break the inherent eigen-polarization constraint over the wavelengths in mid-infrared. This recipe enables to select arbitrary orthogonal polarization basis at individual wavelength independently, therefore alleviating the crosstalk and efficiency degradation. A six-channel all-silicon metasurface is specifically presented to project focused mid-infrared light to distinct positions at three wavelengths, each with a pair of arbitrarily chosen orthogonal polarizations. An isolation ratio of 117 between neighboring polarization channels is experimentally recorded, exhibiting detection sensitivity one order of magnitude higher than existing infrared detectors. Remarkably, the high aspect ratio ~30 of our meta-structures manufactured by deep silicon etching technology at temperature -150 °C guarantees the large and precise phase dispersion control over a broadband from 3 to 4.5 µm. We believe our results would benefit the noise-immune mid-infrared detections in remote sensing and space-to-ground communications.

19.
Artículo en Inglés | MEDLINE | ID: mdl-36888888

RESUMEN

The epitaxial growth of low-dimensional tin chalcogenides SnX (X = S, Se) with a controlled crystal phase is of particular interest since it can be utilized to tune optoelectronic properties and exploit potential applications. However, it still remains a great challenge to synthesize SnX nanostructures with the same composition but different crystal phases and morphologies. Herein, we report a phase-controlled growth of SnS nanostructures via physical vapor deposition on mica substrates. The phase transition from α-SnS (Pbnm) nanosheets to ß-SnS (Cmcm) nanowires can be tailored by the reduction of growth temperature and precursor concentration, which originates from a delicate competition between SnS-mica interfacial coupling and phase cohesive energy. The phase transition from the α to ß phase not only greatly improves the ambient stability of SnS nanostructures but also leads to the band gap reduction from 1.03 to 0.93 eV, which is responsible for fabricated ß-SnS devices with an ultralow dark current of 21 pA at 1 V, an ultrafast response speed of ≤14 µs, and broadband spectra response from the visible to near-infrared range under ambient condition. A maximum detectivity of the ß-SnS photodetector arrives at 2.01 × 108 Jones, which is about 1 or 2 orders of magnitude larger than that of α-SnS devices. This work provides a new strategy for the phase-controlled growth of SnX nanomaterials for the development of highly stable and high-performance optoelectronic devices.

20.
Adv Sci (Weinh) ; 10(11): e2205813, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36782097

RESUMEN

Owing to the large built-in field for efficient charge separation, heterostructures facilitate the simultaneous realization of a low dark current and high photocurrent. The lack of an efficient approach to engineer the depletion region formed across the interfaces of heterojunctions owing to doping differences hinders the realization of high-performance van der Waals (vdW) photodetectors. This study proposes a ferroelectric-controlling van der Waals photodetector with vertically stacked two-dimensional (2D) black phosphorus (BP)/indium selenide (In2 Se3 ) to realize high-sensitivity photodetection. The depletion region can be reconstructed by tuning the polarization states generated from the ferroelectric In2 Se3 layers. Further, the energy bands at the heterojunction interfaces can be aligned and flexibly engineered using ferroelectric field control. Fast response, self-driven photodetection, and three-orders-of-magnitude detection improvements are achieved in the switchable visible or near-infrared operation bands. The results of the study are expected to aid in improving the photodetection performance of vdW optoelectronic devices.

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