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1.
Inorg Chem ; 63(14): 6465-6473, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38528435

ABSTRACT

Two-dimensional inorganic-organic hybrid layered semiconductors are actively studied because of their naturally formed multiquantum well (MQW) structures and associated optical, photoelectric, and quantum optics characteristics. Silver benzeneselenolate (AgSePh, Ph = C6H5) is a new member of such hybrid layered materials, but has not fully been exploited. Herein, we present a quasi-solution method to prepare high quality free-standing AgSePh flake-like microcrystals by reacting diphenyl diselenide (Ph2Se2) with silver nanoparticles. The resultant AgSePh microflakes exhibit room-temperature (RT) resolvable MQW-induced quasi-particle quantization and interesting optical properties, such as three distinct excitonic resonance absorptions X1 (2.67 eV), X2 (2.71 eV), and X3 (2.83 eV) in the visible region, strong narrow-line width blue photoluminescence at ∼2.64 eV (470 nm) from the radiative recombination of the X1 exciton state, and a large exciton binding energy (∼0.35 eV). Furthermore, AgSePh microcrystals show high stability under water, oxygen, and heat environments, while above 220 °C, they will thermally decompose to silver and Ph2Se2 as evidenced by a combination of thermogravimetry and differential scanning calorimetry and pyrolysis-coupled gas chromatography-mass spectrometry studies. Finally, a comparison is extended between AgSePh and other metal benzeneselenolates, benzenethiolates, and alkanethiolates to clarify differences in their solubility, decomposition/melting temperature, and pyrolytic products.

2.
Proc Natl Acad Sci U S A ; 121(9): e2319286121, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38394244

ABSTRACT

Hydrogen (H2) and hydrogen peroxide (H2O2) play crucial roles as energy carriers and raw materials for industrial production. However, the current techniques for H2 and H2O2 production rely on complex catalysts and involve multiple intermediate steps. In this study, we present a straightforward, environmentally friendly, and highly efficient laser-induced conversion method for overall water splitting to simultaneously generate H2 and H2O2 at ambient conditions without any catalysts. The laser direct overall water splitting approach achieves an impressive light-to-hydrogen energy conversion efficiency of 2.1%, with H2 production rates of 2.2 mmol/h and H2O2 production rates of 65 µM/h in a limited reaction area (1 mm2) within a short real reaction time (0.36 ms/h). Furthermore, we elucidate the underlying physics and chemistry behind the laser-induced water splitting to produce H2 and H2O2. The laser-induced cavitation bubbles create an optimal microenvironment for water-splitting reactions because of the transient high temperatures (104 K) surpassing the chemical barrier required. Additionally, their rapid cooling rate (1010 K/s) hinders reverse reactions and facilitates H2O2 retention. Finally, upon bubble collapse, H2 is released while H2O2 remains dissolved in the water. Moreover, a preliminary amplification experiment demonstrates the potential industrial applications of this laser chemistry. These findings highlight that laser-based production of H2 and H2O2 from water holds promise as a straightforward, environmentally friendly, and efficient approach on an industrial scale beyond conventional chemical catalysis.

3.
ACS Nano ; 2024 Feb 05.
Article in English | MEDLINE | ID: mdl-38315041

ABSTRACT

Unraveling the configuration-activity relationship and synergistic enhancement mechanism (such as real active center, electron spin-state, and d-orbital energy level) for triatomic catalysts, as well as their intrinsically bifunctional oxygen electrocatalysis, is a great challenge. Here we present a triatomic catalyst (TAC) with a trinuclear active structure that displays extraordinary oxygen electrocatalysis for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), greatly outperforming the counterpart of single-atom and diatomic catalysts. The aqueous Zn-air battery (ZAB) equipped with a TAC-based cathode exhibits extraordinary rechargeable stability and ultrarobust cycling performance (1970 h/3940 cycles at 2 mA cm-2, 125 h/250 cycles at 10 mA cm-2 with negligible voltage decay), and the quasi-solid-state ZAB displays outstanding rechargeability and low-temperature adaptability (300 h/1800 cycles at 2 mA cm-2 at -60 °C), outperforming other state-of-the-art ZABs. The experimental and theoretical analyses reveal the symmetry-breaking CoN4 configuration under incorporation of neighboring metal atoms (Fe and Cu), which leads to d-orbital modulation, a low-shift d band center, weakened binding strength to the oxygen intermediates, and decreased energy barrier for bifunctional oxygen electrocatalysis. This rational tricoordination design as well as an in-depth mechanism analysis indicate that hetero-TACs can be promisingly applied in various electrocatalysis applications.

4.
Sensors (Basel) ; 24(3)2024 Jan 23.
Article in English | MEDLINE | ID: mdl-38339456

ABSTRACT

Real-time monitoring and timely risk warnings for the safety, health, and fatigue of underground miners are essential for establishing intelligent mines, enhancing the safety of production, and safeguarding the well-being of miners. This concerns the collection, transmission, and processing of relevant data. To minimize physical strain on miners, data collection functions are consolidated into two wearable terminals: an electronic bracelet equipped with reliable, low-power components for gathering vital sign data and transmitting them via Bluetooth and a miner lamp that integrates multi-gas detection, personnel positioning, and wireless communication capabilities. The gas sensors within the miner lamp undergo regular calibration to maintain accuracy, while the positioning tag supports round-trip polling to ensure a deviation of less than 0.3 m. Data transmission is facilitated through the co-deployment of 5G communication and UWB positioning base stations, with distributed MIMO networking to minimize frequent cell handovers and ensure a low latency of no more than 20 ms. In terms of data processing, a backpropagation mapping model was developed to estimate miners' fatigue, leveraging the strong correlation between saliva pH and fatigue, with vital signs as the input layer and saliva pH as the output layer. Furthermore, a unified visualization platform was established to facilitate the management of all miners' states and enable prompt emergency response. Through these optimizations, a monitoring system for underground miners' status based on mine IoT technology can be constructed, meeting the requirements of practical operations.

5.
J Am Chem Soc ; 146(7): 4864-4871, 2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38334947

ABSTRACT

As a good carrier of hydrogen, ammonia-water has been employed to extract hydrogen in many ways. Here, we demonstrate a simple, green, ultrafast, and highly efficient method for hydrogen extraction from ammonia-water by laser bubbling in liquids (LBL) at room temperature and ambient pressure without catalyst. A maximum apparent yield of 33.7 mmol/h and a real yield of 93.6 mol/h were realized in a small operating space, which were far higher than the yields of most hydrogen evolution reactions from ammonia-water under ambient conditions. We also established that laser-induced cavitation bubbles generated a transient high temperature, which enabled a very suitable environment for hydrogen extraction from ammonia-water. The laser used here can serve as a demonstration of potentially solar-pumped catalyst-free hydrogen extraction and other chemical synthesis. We anticipate that the LBL technique will open unprecedented opportunities to produce chemicals.

6.
Adv Mater ; 36(16): e2312541, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38252894

ABSTRACT

The positive photoconductive (PPC) effect is a well-established primary detection mechanism employed by photodetectors. In contrast, the negative photoconductive (NPC) effect is not extensively investigated thus far, and research on the NPC effect is still in its early stage. Herein, a quaternary van der Waals material, AgBiP2Se6 atomic layers, is discovered to achieve a giant NPC effect. Through experimental observations in a Graphene/AgBiP2Se6/ Graphene-based vertical photodetector, an irreversible conversion is identified from common PPC photoresponse to atypical NPC photoresponse. Notably, this device demonstrates an exceptionally high negative responsivity (R) of 4.9 × 105 A W-1, surpassing the previous records for NPC photodetectors. Additionally, it exhibits remarkable optoelectronic performances, including an external quantum efficiency of 1.3 × 108% and a detectivity (D) of 3.60 × 1012 Jones. The exceptionally high NPC photoresponse observed in this device can be attributed to the swift suppression of photogenerated free carriers at robust recombination centers situated at significant depths, induced by the elevated drain-source voltage bias. The remarkably high NPC photoresponse also positions AgBiP2Se6 as a promising 2D material for multifunctional optoelectronic devices and an excellent platform for systematic exploration of the NPC effect.

7.
J Colloid Interface Sci ; 659: 878-885, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38219306

ABSTRACT

Cocatalysts play a key role in improving photocatalytic performance by enhancing conductivity and providing an enormous number of active sites simultaneously. However, cocatalysts are usually made of noble metals such as Pt, which are expensive and rare. Therefore, cocatalysts derived from cheap and abundant elements are highly desirable. Here, for the first time, we demonstrate that NiCS3, which is made from nickel that is abundant and costs less than 0.04 % of Pt, is an effective substitute for Pt cocatalysts for the photocatalytic activity of CdS nanorods in hydrogen evolution reaction (HER). Under visible light, the NiCS3/CdS composite with NiCS3 as the cocatalyst achieved an astonishing H2 production of 61.9 mmol·g-1·h-1 while maintaining high stability, which is 14 times higher than that observed when using CdS alone and nearly 2 times higher than that of Pt/CdS. We also established that the metallicity of NiCS3 results in good carrier conductivity, which promotes the electron transfer and the separation of photo-induced carriers. Due to the appropriate adsorption energy ΔGH*, NiCS3 more readily adsorbs hydrogen protons and desorbs molecular hydrogen during the photocatalytic process compared with Pt. Additionally, NiCS3 can effectively inhibit the photo-corrosion effect of CdS itself, ensuring a good stability of HER. These results suggest that NiCS3 is a promising substitute for Pt cocatalysts.

8.
Mater Horiz ; 11(4): 995-1007, 2024 Feb 19.
Article in English | MEDLINE | ID: mdl-38047955

ABSTRACT

Transcutaneous energy-harvesting technology based on ultrasound-driven piezoelectric nanogenerators is the most promising technology in medical and industrial applications. Based on ultrasonic coupling effects at the interfaces, the interfacial architecture is a critical parameter to attain desirable electromechanical properties of nanocomposites. Herein, we successfully synthesized core-conductive shell-structured BaTiO3@Carbon [BT@Carbon] nanoparticles [NPs] as nanofillers to design implantable poly(vinylidenefluoride-co-chlorotrifluoroethylene)/BT@Carbon [P(VDF-CTFE)/BT@Carbon] piezoelectric nanogenerators (PENGs) and actuators for harvesting ultrasound (US) underneath the skin. For US-driven PENGs, the electrons and holes are generated not only from the interfaces between the BT@Carbon NPs and the matrix, but also from the dipoles vibrating in the smaller lamellae of ferroelectric ß-phase crystals in poled nanocomposites. Remarkably, P(VDF-CTFE)/BT@Carbon piezoelectric nanogenerators could attain an extraordinary output power of 521 µW cm-2 under ultrasound stimulation, which is far greater than that of force-induced PVDF-based nanogenerators and other ultrasound-driven triboelectric generators. Furthermore, the US-PENG actuator system, which is composed of an amplifier and a microcontroller, could efficiently convert ultrasonic energy into electricity or instructions to switch on/off small electronics in the tissues and organs of mice. Finally, the nanocomposite-based US-driven PENGs have a good biocompatibility, with no cytotoxicity or immune response in vivo, indicating their potential for developing wireless power generators and actuators for medical implant devices.

9.
Cell Stem Cell ; 31(1): 89-105.e6, 2024 01 04.
Article in English | MEDLINE | ID: mdl-38141612

ABSTRACT

Stem cells are known for their resilience and enhanced activity post-stress. The mammary gland undergoes frequent remodeling and is subjected to recurring stress during the estrus cycle, but it remains unclear how mammary stem cells (MaSCs) respond to the stress and contribute to regeneration. We discovered that cytotoxic stress-induced activation of CD11c+ ductal macrophages aids stem cell survival and prevents differentiation. These macrophages boost Procr+ MaSC activity through IL1ß-IL1R1-NF-κB signaling during the estrus cycle in an oscillating manner. Deleting IL1R1 in MaSCs results in stem cell loss and skewed luminal differentiation. Moreover, under cytotoxic stress from the chemotherapy agent paclitaxel, ductal macrophages secrete higher IL1ß levels, promoting MaSC survival and preventing differentiation. Inhibiting IL1R1 sensitizes MaSCs to paclitaxel. Our findings reveal a recurring inflammatory process that regulates regeneration, providing insights into stress-induced inflammation and its impact on stem cell survival, potentially affecting cancer therapy efficacy.


Subject(s)
Mammary Glands, Animal , Stem Cells , Female , Animals , Cell Differentiation/physiology , Signal Transduction , Paclitaxel/pharmacology , Paclitaxel/metabolism
10.
Commun Biol ; 6(1): 1195, 2023 11 24.
Article in English | MEDLINE | ID: mdl-38001377

ABSTRACT

Type VI secretion systems (T6SSs) deliver effectors into target cells. Besides structural and effector proteins, many other proteins, such as adaptors, co-effectors and accessory proteins, are involved in this process. MIX domains can assist in the delivery of T6SS effectors when encoded as a stand-alone gene or fused at the N-terminal of the effector. However, whether there are other conserved domains exhibiting similar encoding forms to MIX in T6SS remains obscure. Here, we scanned publicly available bacterial genomes and established a database which include 130,825 T6SS vgrG loci from 45,041 bacterial genomes. Based on this database, we revealed six domain families encoded within vgrG loci, which are either fused at the C-terminus of VgrG/N-terminus of T6SS toxin or encoded by an independent gene. Among them, DUF2345 was further validated and shown to be indispensable for the T6SS effector delivery and LysM was confirmed to assist the interaction between VgrG and the corresponding effector. Together, our results implied that these widely distributed domain families with similar genetic configurations may be required for the T6SS effector recruitment process.


Subject(s)
Type VI Secretion Systems , Humans , Type VI Secretion Systems/genetics , Type VI Secretion Systems/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism
11.
Int Microbiol ; 2023 Nov 21.
Article in English | MEDLINE | ID: mdl-37987892

ABSTRACT

We determined whether there exists a complementary pathway of cordycepin biosynthesis in wild-type Cordyceps militaris, high-cordycepin-producing strain C. militaris GYS60, and low-cordycepin-producing strain C. militaris GYS80. Differentially expressed genes were identified from the transcriptomes of the three strains. Compared with C. militaris, in GYS60 and GYS80, we identified 145 and 470 upregulated and 96 and 594 downregulated genes. Compared with GYS80, in GYS60, we identified 306 upregulated and 207 downregulated genes. Gene Ontology analysis revealed that upregulated genes were mostly involved in detoxification, antioxidant, and molecular transducer in GYS60. By Clusters of Orthologous Groups of Proteins and Kyoto Encyclopedia of Genes and Genomes analyses, eight genes were significantly upregulated: five genes related to purine metabolism, one to ATP production, one to secondary metabolite transport, and one to RNA degradation. In GYS60, cordycepin was significantly increased by upregulation of ATP production, which promoted 3',5'-cyclic AMP production. Cyclic AMP accelerated 3'-AMP accumulation, and cordycepin continued to be synthesized and exported. We verified the novel complementary pathway by adding the precursor adenosine and analyzing the expression of four key genes involved in the main pathway of cordycepin biosynthesis. Adenosine addition increased cordycepin production by 51.2% and 10.1%, respectively, in C. militaris and GYS60. Four genes in the main pathway in GYS60 were not upregulated.

12.
Mater Horiz ; 10(9): 3369-3381, 2023 Aug 29.
Article in English | MEDLINE | ID: mdl-37404203

ABSTRACT

In this study, cost-efficient atmospheric pressure chemical vapor deposition has been successfully developed to produce well-aligned high-quality monocrystalline Bi2S3 nanowires. By virtue of surface strain-induced energy band reconstruction, the Bi2S3 photodetectors demonstrate a broadband photoresponse across 370.6 to 1310 nm. Upon a gate voltage of 30 V, the responsivity, external quantum efficiency, and detectivity reach 23 760 A W-1, 5.55 × 106%, and 3.68 × 1013 Jones, respectively. The outstanding photosensitivity is ascribed to the high-efficiency spacial separation of photocarriers, enabled by synergy of the axial built-in electric field and type-II band alignment, as well as the pronounced photogating effect. Moreover, a polarization-discriminating photoresponse has been unveiled. For the first time, the correlation between quantum confinement and dichroic ratio is systematically explored. The optoelectronic dichroism is established to be negatively correlated with the cross dimension (i.e., width and height) of the channel. Specifically, upon 405 nm illumination, the optimized dichroic ratio reaches 2.4, the highest value among the reported Bi2S3 photodetectors. In the end, proof-of-concept multiplexing optical communications and broadband lensless polarimetric imaging have been implemented by exploiting the Bi2S3 nanowire photodetectors as light-sensing functional units. This study develops a quantum tailoring strategy for tailoring the polarization properties of (quasi-)1D material photodetectors whilst depicting new horizons for the next-generation opto-electronics industry.

13.
IEEE Trans Pattern Anal Mach Intell ; 45(11): 13250-13264, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37363835

ABSTRACT

Image view synthesis has seen great success in reconstructing photorealistic visuals, thanks to deep learning and various novel representations. The next key step in immersive virtual experiences is view synthesis of dynamic scenes. However, several challenges exist due to the lack of high-quality training datasets, and the additional time dimension for videos of dynamic scenes. To address this issue, we introduce a multi-view video dataset, captured with a custom 10-camera rig in 120FPS. The dataset contains 96 high-quality scenes showing various visual effects and human interactions in outdoor scenes. We develop a new algorithm, Deep 3D Mask Volume, which enables temporally-stable view extrapolation from binocular videos of dynamic scenes, captured by static cameras. Our algorithm addresses the temporal inconsistency of disocclusions by identifying the error-prone areas with a 3D mask volume, and replaces them with static background observed throughout the video. Our method enables manipulation in 3D space as opposed to simple 2D masks, We demonstrate better temporal stability than frame-by-frame static view synthesis methods, or those that use 2D masks. The resulting view synthesis videos show minimal flickering artifacts and allow for larger translational movements.

14.
Research (Wash D C) ; 6: 0132, 2023.
Article in English | MEDLINE | ID: mdl-37228638

ABSTRACT

Methanol (CH3OH) is a liquid hydrogen (H2) source that effectively releases H2 and is convenient for transportation. Traditional thermocatalytic CH3OH reforming reaction is used to produce H2, but this process needs to undergo high reaction temperature (e.g., 200 °C) along with a catalyst and a large amount of carbon dioxide (CO2) emission. Although photocatalysis and photothermal catalysis under mild conditions are proposed to replace the traditional thermal catalysis to produce H2 from CH3OH, they still inevitably produce CO2 emissions that are detrimental to carbon neutrality. Here, we, for the first time, report an ultrafast and highly selective production of H2 without any catalysts and no CO2 emission from CH3OH by laser bubbling in liquid (LBL) at room temperature and atmospheric pressure. We demonstrate that a super high H2 yield rate of 33.41 mmol·h-1 with 94.26% selectivity is achieved upon the laser-driven process. This yield is 3 orders of magnitude higher than the best value reported for photocatalytic and photothermal catalytic H2 production from CH3OH to date. The energy conversion efficiency of laser light to H2 and CO can be up to 8.5%. We also establish that the far from thermodynamic equilibrium state with high temperature inside the laser-induced bubble and the kinetic process of rapid quenching of bubbles play crucial roles in H2 production upon LBL. Thermodynamically, the high temperature induced using laser in bubbles ensures fast and efficient release of H2 from CH3OH decomposition. Kinetically, rapidly quenching of laser-induced bubbles can inhibit reverse reaction and can keep the products in the initial stage, which guarantees high selectivity. This study presents a laser-driven ultrafast and highly selective production of H2 from CH3OH under normal conditions beyond catalytic chemistry.

15.
J Interv Med ; 6(1): 49-51, 2023 Feb.
Article in English | MEDLINE | ID: mdl-37180373

ABSTRACT

Congenital intrahepatic portosystemic venous shunt (CPSVS), a rare vascular malformation, has been described in both children and adults and can lead to severe neurophysiological complications. However, a standard therapeutic protocol for CPSVS has not been elucidated. With the advantage of minimally invasive techniques, transcatheter embolization has been used to treat CPSVS. The condition is challenging to manage, especially in patients with large or multiple shunts, through which rapid blood flow can cause ectopic embolism. Here, we describe a case of CPSVS with a large shunt that was successfully treated with balloon-occluded retrograde transvenous obliteration with interlocking detachable coils.

16.
J Colloid Interface Sci ; 646: 625-632, 2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37216710

ABSTRACT

As emerging materials, medium-entropy oxides have attracted wide attention for the huge potential in energy storage, catalytic, magnetic and thermal applications. The electronic effect or the strong synergic effect caused by the construction of medium-entropy system leads to the unique properties of catalysis. In this contribution, we reported a medium-entropy CoNiCu oxide as an efficient cocatalyst for enhanced photocatalytic hydrogen evolution reaction. The target product was synthesized by a process of laser ablation in liquids and graphene oxide was applied as a conductive substrate of it, then it was loaded on the photocatalyst g-C3N4. The results showed that the modified photocatalysts exhibited the reduced [Formula: see text] and enhanced abilities of photoinduced charges separation and transfer. Furthermore, a maximum hydrogen production rate was measured to be 1177.52 µmol ·g-1·h-1 under the visible light irradiation, which was about 291 times higher than that of pure g-C3N4. These findings suggest that the medium-entropy CoNiCu oxide serves as an eminent cocatalyst, which offers a possible pathway towards the broadening of the applications of medium-entropy oxides and provides the alternatives to conventional cocatalysts.

17.
Adv Sci (Weinh) ; 10(17): e2206950, 2023 06.
Article in English | MEDLINE | ID: mdl-37088732

ABSTRACT

Owing to their unique advantages, single-electrode triboelectric nanogenerators (SETENGs) have gained wide attention and have been applied in myriad areas, especially in the burgeoning flexible/wearable electronics. However, there is still a lack of a clear understanding of SETENGs. For example, previous simulation models generally put the reference electrode perpendicularly below the working part, but in practice, the reference electrode is designed in various scenarios and noticeable differences in outputs often occur when the reference electrode changes. With SETENGs developing towards wearability and portability, its reference electrode is often required to be constructed inside the device. Consequently, to achieve optimum performance, it is essential to understand the reference electrode's influence on the outputs. Here, the influence of the reference electrode on the performance of SETENGs is systematically investigated and the targeted optimization strategies are thoroughly revealed. First, theoretical simulations are conducted to investigate the reference electrode's effect on the performance of SETENGs with different structures and in various working modes. Secondly, the theoretical results are certified through corresponding experiments. Based on the results, the targeted optimization strategies for SETENGs are comprehensively demonstrated. This work provides fundamental guidance for the development of TENGs and the design and fabrication of new electronic devices.

18.
Front Cardiovasc Med ; 10: 1088575, 2023.
Article in English | MEDLINE | ID: mdl-37063954

ABSTRACT

Autophagy is a conserved lysosomal pathway for the degradation of cytoplasmic proteins and organelles, which realizes the metabolic needs of cells and the renewal of organelles. Autophagy-related genes (ATGs) are the main molecular mechanisms controlling autophagy, and their functions can coordinate the whole autophagic process. Autophagy can also play a role in cardiovascular disease through several key signaling pathways, including PI3K/Akt/mTOR, IGF/EGF, AMPK/mTOR, MAPKs, p53, Nrf2/p62, Wnt/ß-catenin and NF-κB pathways. In this paper, we reviewed the signaling pathway of cross-interference between autophagy and cardiovascular diseases, and analyzed the development status of novel cardiovascular disease treatment by targeting the core molecular mechanism of autophagy as well as the critical signaling pathway. Induction or inhibition of autophagy through molecular mechanisms and signaling pathways can provide therapeutic benefits for patients. Meanwhile, we hope to provide a unique insight into cardiovascular treatment strategies by understanding the molecular mechanism and signaling pathway of crosstalk between autophagy and cardiovascular diseases.

19.
ACS Appl Mater Interfaces ; 15(12): 16244-16252, 2023 Mar 29.
Article in English | MEDLINE | ID: mdl-36939114

ABSTRACT

Hydrogen detection is crucial for the forthcoming hydrogen economy. Here, we present a visual, ultrasensitive, optical hydrogen sensor based on a tunable Fabry-Pérot (FP) resonator, which can fully release the volume expansion of palladium during hydrogenation and transfer this volume expansion into an optical signal. The FP resonator consists of a suspended polymethylmethacrylate/palladium (PMMA/Pd) bilayer on a gold (Au) square-hole array. The bottom of the gold square hole and hydrogen-sensitive PMMA/Pd bilayer form a dynamically tunable FP resonator. When hydrogen gas (H2) is loaded, the hydrogen-induced lateral expanding stress concavely deforms the suspended bilayer downward to the substrate, narrowing the metal-air-metal gap at the center of the hole, and finally leading to a spectral blue shift. Our experimental results show a giant spectral shift of 279 nm with a reflectance variation of 57% on exposure to 0.6% H2 mixed with air. Such an ultrahigh optical response results in a significant color change, enabling visual hydrogen detection. In addition, the sensor has a H2 detection limit down to 0.1% and good recyclability. These advantages indicate that the sensor has excellent potential for hydrogen sensing applications.

20.
Adv Mater ; 35(20): e2211562, 2023 May.
Article in English | MEDLINE | ID: mdl-36893428

ABSTRACT

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.

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