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1.
Nanoscale ; 15(18): 8158-8168, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37017122

RESUMO

For solar cell-triboelectric nanogenerator (TENG) integration, the design of the solid substrate for the TENG device becomes one of the challenges. The TENG needs to have superior contact electrification properties and be transparent so as to ensure light transmittance. Here, by spontaneous polymerization of dichlorodimethylsilane in the absence of any toxic solvent, we have fabricated a controllable liquid-like polydimethylsiloxane brush, featuring hydrophobicity, long-term stability, robustness, and UV resistance. A drop of liquid slides off at tilt angles below 5° and there is dynamic contact angle hysteresis of no more than 10° that can provide strong self-cleaning ability to the solid substrate. This recipe is also applicable to surfaces composed of hydroxyl group-rich cellulose-based surfaces, such as flexible cellulose acetate film (CAF). Importantly, PDMS@CAF, a flexible, transparent, and self-cleaning TENG device with a light transmission rate of 99% or more, was prepared using a conductive polymer film of PH 1000. The hybrid energy harvesting system formed by the combination of this transparent TENG equipped with solar cells is promising for harvesting energy from the environment in different weather conditions.

2.
Adv Mater ; 35(20): e2211562, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36893428

RESUMO

High-resolution imaging is at the heart of the revolutionary breakthroughs of intelligent technologies, and it is established as an important approach toward high-sensitivity information extraction/storage. However, due to the incompatibility between non-silicon optoelectronic materials and traditional integrated circuits as well as the lack of competent photosensitive semiconductors in the infrared region, the development of ultrabroadband imaging is severely impeded. Herein, the monolithic integration of wafer-scale tellurene photoelectric functional units by exploiting room-temperature pulsed-laser deposition is realized. Taking advantage of the surface plasmon polaritons of tellurene, which results in the thermal perturbation promoted exciton separation, in situ formation of out-of-plane homojunction and negative expansion promoted carrier transport, as well as the band bending promoted electron-hole pair separation enabled by the unique interconnected nanostrip morphology, the tellurene photodetectors demonstrate wide-spectrum photoresponse from 370.6 to 2240 nm and unprecedented photosensitivity with the optimized responsivity, external quantum efficiency and detectivity of 2.7 × 107  A W-1 , 8.2 × 109 % and 4.5 × 1015  Jones. An ultrabroadband imager is demonstrated and high-resolution photoelectric imaging is realized. The proof-of-concept wafer-scale tellurene-based ultrabroadband photoelectric imaging system depicts a fascinating paradigm for the development of an advanced 2D imaging platform toward next-generation intelligent equipment.

3.
ACS Nano ; 16(8): 12852-12865, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35914000

RESUMO

A selective-area oxidation strategy is developed to polarize high-symmetry 2D layered materials (2DLMs). The dichroic ratio of the derived O-WS2/WS2 photodetector reaches ∼8, which is competitive among state-of-the-art polarization photodetectors. Finite-different time-domain simulations consolidate that the polarization-sensitive photoresponse is associated with anisotropic spacial confinement, which gives rise to distinct dielectric contrasts for linearly polarized light of various directions and thus the polarization-dependent near-field distribution. Furthermore, selective-area oxidation treatment brings about dual effects, comprising the in situ formation of seamless in-plane WS2 homojunctions by thickness tailoring and the formation of out-of-plane O-WS2/WS2 heterojunctions. As a consequence, the recombination of photocarriers is markedly suppressed, resulting in outstanding photosensitivity with the optimized responsivity, external quantum efficiency, and detectivity of 0.161 A/W, 49.4%, and 1.4 × 1011 Jones for an O-WS2/WS2 photodetector in a self-powered mode. A scheme of multiplexing optical communications is revealed by harnessing the intensity and polarization state of light as independent transmission channels. Furthermore, dynamic encryption by leveraging the polarization state as a secret key is proposed. In the end, broad universality is reinforced through the induction of linear dichroism within 2D WSe2 crystals. On the whole, this study provides an additional perspective on polarization optoelectronics based on 2DLMs.

4.
Mater Horiz ; 9(9): 2364-2375, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35876307

RESUMO

Low light absorption and limited carrier lifetime are critical obstacles inhibiting further performance improvement of 2D layered material (2DLM) based photodetectors, while scalable fabrication is an ongoing challenge prior to commercialization from the lab to market. Herein, wafer-scale SnS/ZIS hierarchical nanofilms, where out-of-plane SnS (O-SnS) is modified onto in-plane ZIS (I-ZIS), have been achieved by pulsed-laser deposition. The derived O-SnS/I-ZIS photodetector exhibits markedly boosted sensitivity as compared to a pristine ZIS device. The synergy of multiple functionalities contributes to the dramatic improvement, including the pronounced light-trapping effect of O-SnS by multiple scattering, the high-efficiency spatial separation of photogenerated electron-hole pairs by a type-II staggered band alignment and the promoted carrier transport enabled by the tailored electronic structure of ZIS. Of note, the unique architecture of O-SnS/I-ZIS can considerably expedite the carrier dynamics, where O-SnS promotes the electron transfer from SnS to ZIS whilst the I-ZIS enables high-speed electron circulation. In addition, the interlayer transition enables the bridging of the effective optical window to telecommunication wavelengths. Moreover, monolithic integration of arrayed devices with satisfactory device-to-device variability has been encompassed and a proof-of-concept imaging application is demonstrated. On the whole, this study depicts a fascinating functional coupling architecture toward implementing chip-scale integrated optoelectronics.

5.
Nanoscale ; 14(16): 6228-6238, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35403635

RESUMO

Over the past decade, 2D elemental semiconductors have emerged as an ever-increasingly important group in the 2D material family due to their simple crystal structures and compositions, and versatile physical properties. Taking advantage of the relatively small bandgap, outstanding carrier mobility, high air-stability and strong interactions with light, 2D tellurium (Te) has emerged as a compelling candidate for use in ultra-broadband photoelectric technologies. In this study, high-quality centimeter-scale Te nanofilms have been successfully produced by exploiting pulsed-laser deposition (PLD). By performing deposition on pre-patterned SiO2/Si substrates, a Te/Si 2D/3D heterojunction array is formed in situ. To our delight, taking advantage of the relatively small bandgap of Te, the Te/Si photodetectors demonstrate an ultra-broadband photoresponse from ultraviolet to near-infrared (370.6 nm to 2240 nm), enabling them to serve as important alternatives to conventional 2D materials such as MoS2. In addition, an outstanding on/off ratio of ∼108 and a fast response rate (a response/recovery time of 3.7 ms/4.4 ms) are achieved, which is associated with the large band offset and strong interfacial built-in electric field that contribute to suppressing the dark current and separating photocarriers. Beyond these, a 35 × 35 matrix array has been successfully constructed, where the devices exhibit comparable properties, with a production yield of 100% for 100 randomly tested devices. The average responsivity, external quantum efficiency and detectivity reach 249 A W-1, 76 350% and 1.15 × 1011 Jones, respectively, making the Te/Si devices among the best-performing 2D/3D heterojunction photodetectors. On the whole, this study has established that PLD is a promising technique for producing high-quality Te nanofilms with good scalability, and the Te/Si 2D/3D heterojunction provides a promising platform for implementing high-performance ultra-broadband photoelectronic technologies.

6.
Small Methods ; 6(2): e2101046, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34935297

RESUMO

Low light absorption and limited carrier lifetime are two limiting factors hampering the further breakthrough of the performance of 2D materials (2DMs)-based photodetectors. This study proposes an ingenious dielectric engineering strategy toward boosting the photosensitivity. Periodic dielectric structures (PDSs), including SiO2 /h-BN, SiO2 /Al2 O3 , and SiO2 /SrTiO3 (STO), are exploited to couple with 2D photosensitive channels (denoted as PDS-2DMs). The responsivity, external quantum efficiency, and detectivity of an optimized SiO2 /STO(300 nm) -WSe2 photodetector reach 89081 A W-1 , 2.7 × 107 %, and 1.8 × 1013 Jones, respectively. These performance metrics are orders of magnitude higher than a pristine WSe2 photodetector, enabling reliable sub-1 pW weak light detection. Based on systematic characterizations and first-principle calculations, such dramatic performance improvement is associated with the promoted direct bandgap transition, reduced exciton binding energy, and PDS-induced periodic intramolecular built-in electric field across the atomically thin channels, which efficiently separates the photoexcited electron-hole pairs. More inspiringly, this strategy is also successfully exploited to 2D WS2 photodetectors, demonstrating broad applicability. As a whole, this work promises an exceptional avenue to ameliorate 2DM photodetectors and opens up a new horizon "dielectric optoelectronics," simultaneously highlighting the role of dielectric environment during analyzing the fundamentals of 2DM devices.

7.
Nanoscale ; 13(11): 5660-5669, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33724286

RESUMO

Heterojunctions based on low-dimensional materials can combine the superiorities of each component and realize novel properties. Herein, a mixed-dimensional heterojunction comprising multilayer WS2, CdS microwire, and few-layer WS2 has been demonstrated. The working mechanism and its application in a photodetector are investigated. The multilayer WS2 and CdS microwire are utilized to provide efficient light absorption, while the few-layer WS2 is utilized to passivate interfacial impurity scattering. In addition, based on the reasonable band alignment of the components, three built-in electric fields are formed, which efficiently separate the photo-generated carriers and enhance the photocurrent. In particular, the photo-generated electrons are trapped in CdS, while the photo-generated holes circulate in the external circuit, leading to a high photoconductivity gain. Motivated by these, we constructed a device that exhibits a photoresponsivity of ∼4.7 A W-1, a response/recovery time of 13.7/15.8 ms, and a detectivity of 3.4 × 1012 Jones, which are much better than the counterparts. All of these clearly demonstrate the importance of advanced device designs for realizing high performance optoelectronic devices.

8.
Nanoscale ; 12(13): 7196-7205, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32195529

RESUMO

Self-powered photodetectors have triggered extensive attention in recent years due to the advantages of high sensitivity, fast response, low power consumption, high level of integration and wireless operation. To date, most self-powered photodetectors are implemented through the construction of either heterostructures or asymmetric electrode material contact, which are complex to process and costly to produce. Herein, for the first time, we achieved a self-powered operation by adopting a geometrical asymmetry in the device architecture, where a triangular non-layered 2D In2S3 flake with an asymmetric contact is combined with the traditional photogating effect. Importantly, the device achieves excellent photoresponsivity (740 mA W-1), high detectivity (1.56 × 1010 Jones), and fast response time (9/10 ms) under zero bias. Furthermore, the asymmetric In2S3/Si photodetector manifests long-term stability. Even after 1000 cycles of operation, the asymmetric In2S3/Si device displays negligible performance degradation. In sum, the above results highlight a novel route towards self-powered photodetectors with high performance, simple processing and structure in the future.

9.
Small ; 15(47): e1904912, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31608603

RESUMO

Silicon-based electronic devices, especially graphene/Si photodetectors (Gr/Si PDs), have triggered tremendous attention due to their simple structure and flexible integration of the Schottky junction. However, due to the relatively poor light-matter interaction and mobility of silicon, these Gr/Si PDs typically suffer an inevitable compromise between photoresponsivity and response speed. Herein, a novel strategy for coupling 2D In2 S3 with Gr/Si PDs is demonstrated. The introduction of the double-heterojunction design not only strengthens the light absorption of graphene/Si but also combines the advantages of the photogating effect and photovoltaic effect, which suppresses the dark current, accelerates the separation of photogenerated carriers, and brings photoconductive gain. As a result, In2 S3 /graphene/Si devices present an ultrahigh photoresponsivity of 4.53 × 104 A W-1 and fast response speed less than 40 µs, simultaneously. These parameters are an order of magnitude higher than pristine Gr/Si PDs and among the best values compared with reported 2D materials/Si heterojunction PDs. Furthermore, the In2 S3 /graphene/Si PD expresses outstanding long-term stability, with negligible performance degradation even after 1 month in air or 1000 cycles of operation. These findings highlight a simple and novel strategy for constructing high-sensitivity and ultrafast Gr/Si PDs for further optoelectronic applications.

10.
Fish Shellfish Immunol ; 93: 732-742, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31415901

RESUMO

This study evaluates the effect of dietary supplementation of immunostimulants on the Chinese mitten crab (Eriocheir sinensis) with a single administration of mannan oligosaccharide (MOS), or its combination with either ß-glucan or with inulin for 8 weeks. Four diets included an untreated control diet (C), MOS alone (3 g kg-1, M), MOS with ß-glucan (3 g kg -1 MOS + 1.5 g kg -1 ß-glucan, MB), and MOS with inulin (3 g kg -1 MOS + 10 g kg -1 inulin, MI). The weight gain and specific growth rate of the crabs fed M, MB, and MI diets were improved by lowing feed conversion ratio. The growth and feed utilization of the crabs fed the MB diet were improved compared with the other three groups. The crabs fed the M, MB and MI diets showed a higher intestinal trypsin activity than that in the M and control groups. The highest trypsin activity in the hepatopancreas was observed in the MB group. Crabs fed M, MB and MI diets increased antioxidant system-related enzyme activities, but reduced malondialdehyde. The highest activities of alkaline phosphatase, acid phosphatase, lysozyme and phenol oxidase in the gut and the respiratory burst of the crabs were found in the MB group. The MB diet promoted the mRNA expression of E. sinensis immune genes (ES-PT, ES-Relish, ES-LITAF, p38MAPK and Crustin) compared with the control. After 3 days of infection with Aeromonas hydrophila, the highest survival of crabs was also found in the MB group. This study indicates that the combination of MOS with ß-glucan or with inulin can improve growth, antioxidant capacity, non-specific immunity and disease resistance in E. sinensis.


Assuntos
Adjuvantes Imunológicos/farmacologia , Braquiúros/imunologia , Imunidade Inata/efeitos dos fármacos , Inulina/farmacologia , Mananas/farmacologia , Oligossacarídeos/farmacologia , beta-Glucanas/farmacologia , Aeromonas hydrophila/fisiologia , Animais , Antioxidantes/metabolismo , Braquiúros/crescimento & desenvolvimento , Braquiúros/metabolismo , Braquiúros/microbiologia , Distribuição Aleatória
11.
Fish Shellfish Immunol ; 93: 463-473, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31374316

RESUMO

To investigate the effects of arginine (Arg) on the growth, antioxidant capacity, immunity and disease resistance of juvenile Chinese mitten crab, three diets containing Arg levels at 1.72% (control), 2.73% and 3.72% were formulated and fed to Chinese mitten crab (0.22 ±â€¯0.03 g) for eight weeks. The weight gain, ecdysterone and growth hormone in the serum, relative expression of insulin-like growth factor 2 in the hepatopancreas significantly increased in crabs fed the 2.73% and 3.72% Arg diets. The protein and lipid contents significantly increased in crabs fed the 3.72% Arg diet. The feed conversion ratios in crabs fed the diets with Arg additions were lower than in the control. Arg supplementation also enhanced the antioxidative capacity by increasing the activities of superoxide dismutase, catalase and the relative expression of Kelch-like ECH-associated protein 1 gene in the hepatopancreas, which subsequently decreased malondialdehyde content in the hepatopancreas. Besides, Arg also decreased nitric oxide content in the serum and the activity of nitric oxide synthetase in the hepatopancreas. The relative mRNA levels of crustin, relish, lysozyme and cryptocyanin genes were significantly upregulated by Arg supplementation. The activities of acid phosphatase and alkaline phosphatase in the serum significantly increased in crabs fed the 3.72% Arg diet than those in the control. Similarly, the relative mRNA levels of crustin, cryptocyanin and proPO genes were significantly upregulated in crabs fed the 2.73% Arg diet after lipopolysaccharide challenge, and in crabs fed the 3.72% Arg diet after the Poly (I:C) challenge. The crabs fed the 2.73% and 3.72% Arg diets had higher survival rate after bacterial infection than those fed the control diet. This study indicates that the addition of Arg to the diet at 2.7-3.7% can improve the growth, survival, antioxidant capacity, immunity and disease resistance in juvenile Chinese mitten crab.


Assuntos
Arginina/metabolismo , Braquiúros/imunologia , Resistência à Doença/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Ração Animal/análise , Animais , Arginina/administração & dosagem , Braquiúros/efeitos dos fármacos , Braquiúros/crescimento & desenvolvimento , Braquiúros/metabolismo , Dieta/veterinária , Suplementos Nutricionais/análise , Imunidade Inata/imunologia , Distribuição Aleatória
12.
Zhonghua Er Bi Yan Hou Ke Za Zhi ; 39(6): 349-52, 2004 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-15469080

RESUMO

OBJECTIVE: To evaluate the value of Advantage Windows 3.1 (AW 3.1) software for anatomical study of nasofrontal region, and to study the CT characteristics of nasofrontal region which related to the frontal sinus surgery. METHODS: Eighty patients underwent axial consecutive computed tomography scans and these data were studied with AW 3.1 software which provided reconstructional imaging of continuous coronal, sagittal, axial sections. Some related structures of nasofrontal region were studied and measured. RESULTS: AW 3.1 software could identify and measure the following structures accurately: The diameter of frontal sinus was (22.5 +/- 8.6) mm in height, (16.3 +/- 6.8) mm in depth, (23.8 +/- 9.8) mm in breadth. The diameter of frontal sinus ostium: the anterior-posterior diameter was (7.3 +/- 1.7) mm, the transverse diameter was (8.5 +/- 1.9) mm. The width of nasal beak of frontal bone(5.9 +/- 1.4 ) mm. The distance of frontal sinus ostium to the floor of columella nasi and the corresponding angle to the nasal floor were (60.8 +/- 4.2) mm and (70.1 +/- 4.7) degrees. The superior attachment sites of the uncinate process were as follows: lamina papyracea 41%, posteromedial wall of agger nasi cell 11%, middle turbinate 19%, anterior skull base 16%, superior bifurcation 13%. The cells could impinge on the frontal recess to cause obstruction (terminal recess 38.8%, anterior ethmoid cell 27.6%, agger nasi cells 24.5%). The accessory cells could impinge on the frontal sinus (perifrontal cells 32.7%, superaorbital cells 38.8%, intersinus septal cells 32.0%). There was significant difference between two groups of characteristics of nasofrontal region. CONCLUSIONS: AW 3.1 software is a helpful and powerful new tool for anatomical study of nasofrontal region and for preoperative evaluation. The structures of nasofrontal region are complex and various, frontal sinusitis almost always results from the obstruction of frontal sinus outflow tract. These results of anatomical study of nasofrontal region are helpful in directing the functional endoscopic surgery in frontal sinus.


Assuntos
Seio Frontal/diagnóstico por imagem , Sinusite Frontal/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Seio Frontal/anatomia & histologia , Sinusite Frontal/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Software
13.
Zhonghua Er Bi Yan Hou Ke Za Zhi ; 37(5): 360-2, 2002 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-12772457

RESUMO

OBJECTIVE: To explore the feasibility of transnasal endoscopic surgery to treat some kinds of diseases within orbit by ethmoidal-lamina papyracea approach, and put forward the basic principle of surgical management. METHODS: A total of 10 cases undergone the endoorbital operation by transnasal endoscopic ethmoidal-lamina papyracea approach, including foreign body 4 cases, sponge haemangioma 1 case, invaded and metastatic carcinoma 5 cases. RESULTS: Successful removing of foreign body from endoorbital for 3 cases, and 1 failure. One case of sponge haemangioma was removed completely. One case of metastatic tumour from nasopharyngeal carcinoma was resected, with no relapse and vision recovered to 0.6 during follow-up period of 4 years. Four cases of invaded carcinoma from ethmosphenoidal sinus were resected completely. Follow-up for 1-4 years showed no relapse. CONCLUSION: The endoorbital region inside the optic nerve can be controlled by transnasal endoscopic ethmoidal-lamina papyracea approach. The advanced radiotherapy provides favourable conditions for conservative surgery of endoorbital carcinoma.


Assuntos
Endoscopia , Seio Etmoidal/cirurgia , Corpos Estranhos no Olho/cirurgia , Órbita/cirurgia , Neoplasias Orbitárias/cirurgia , Adulto , Endoscopia/métodos , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Otorrinolaringológicos/métodos
14.
Zhonghua Er Bi Yan Hou Ke Za Zhi ; 37(6): 443-6, 2002 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-12966806

RESUMO

OBJECTIVE: To study feasibility and indication of cranialbase surgery by transnasal endoscopic approach. METHODS: Nine cases treated by transnasal were analysed. Those cases included foreign body, olfactory neuroblastoma, meningoma and inverted papilloma in anterior cranial fossa, sinuses sphenoidalis macrosis cyst invading middle cranial fossa, primary cholesteatoma and space occupying lesion in middle cranial fossa. RESULT: The complications were not occurred in all cases. Follow-up survey 1-7 years, no-relapse was occurred. CONCLUSION: It is probability that surgery lesion be close skull base by transnasal endoscopic approach, but indication must be exactitude selected. The operator should be have firm anatomic, skilled operation and richness experience. The malignancy lesion should be compositive treatment after surgery.


Assuntos
Neoplasias Encefálicas/cirurgia , Craniotomia/métodos , Endoscopia , Adolescente , Adulto , Idoso , Criança , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Base do Crânio/cirurgia
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