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Highlights: [•] Metal-semiconductor-metal (MSM) structure detectors with diverse finger spacings were fabricated on the sputtered TiO2 films. [•] High quality TiO2 films and good Au/TiO2 Schottky contacts were achieved. [•] The detectors exhibit lower dark current and higher UV-to-visible rejection ratio. [•] The mechanism of diverse finger spacing on the device performances is analyzed. [•] The detectors are promising in commercial production due to low cost and ease of fabrication process. [ABSTRACT FROM AUTHOR]

The redclaw crayfish (Cherax quadricarinatus) is a freshwater crayfish species endemic to northern Australia and Papua New Guinea that is the focus of a growing culture industry in number of regions around the world. Here we isolated and characterized 15 microsatellite loci from Cherax quadricarinatus and tested variability of the loci in 66 unrelated cultured individuals. Thirteen of 15 microsatellite loci were polymorphic. Number of alleles per locus ranged from two to seven while observed and expected heterozygosities ranged from 0.172 to 0.985 and from 0.373 to 0.778, respectively. Eleven loci conformed to Hardy–Weinberg equilibrium in the sampled population. These microsatellite loci developed here provide an important resource for studying genetic diversity and population structure in redclaw crayfish and potentially in other related species. [ABSTRACT FROM PUBLISHER]

2D van der Waals (vdWs) heterostructure photodetectors have captured significant interest for their ability to achieve substantial optical conductivity gain and device tunability. However, the light absorption in ultrathin 2D inorganic vdWs devices is generally weak that leads to low detectivity. In addition, the intrinsic defects in 2D semiconductors cause significant carrier trapping and scattering by defect states during the transport process, which seriously restricts the response speed of the device. In this paper, a molybdenum tungsten disulfide (Mo0.1W0.9S2) is used to replace the conventional 2D semiconductor, while the light absorption efficiency of the device is significantly enhanced by the adoption of N’‐ Dimethyl‐3,4,9,10‐perylenedicarboximide (Me‐PTCDI), thus achieving both fast response and high detectivity. A series of type‐II organic/inorganic hybrid vdWs heterostructure photodetectors is systematically investigated based on Me‐PTCDI and Mo0.1W0.9S2. In particular, the device incorporating monolayer (ML) Me‐PTCDI and few‐layer (FL) Mo0.1W0.9S2 demonstrates a detectivity of up to 4.4 × 1011 Jones and a response time of 24.9 µs. By utilizing the device as a light sensing pixel, a single‐detecting pixel imaging system is demonstrated with high precision, showcasing promising prospects in fast imaging applications. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations have revealed the important roles of hydration shells of ions transported through ultrathin carbon nanotubes (CNTs). In particular, ions driven by electric fields tend to drag their hydration shells behind them, while for ions transported by pressure, their hydration shells can actively drive them. Given the different binding strengths of hydration shells to ions of different sizes, these active roles of hydration shells affect the relative entry rates and driving speeds of ions in CNTs. [ABSTRACT FROM AUTHOR]

Contact electrification (triboelectrification) (CE) is a universal phenomenon in ambient environment and has been recorded for more than 2600 years. Nonetheless, the intrinsic mechanism of CE still remains controversial. Herein, based on first‐principles theory, the underlying mechanism in CE is systematically investigated between metallic MXenes and semiconductive MoS2. The results show that the work functions of contacting materials dominate the direction of electron transfer during CE process. That is, the electron will be transferred from the material with low work function to the one with high work function. The theoretical prediction is verified experimentally through investigating triboelectric probes based on MXenes and MoS2 nanomaterials. Additionally, it is noted that the interfacial potential barrier and the work function difference together modulate the amount of transferred electron. Electron transfer mainly occurs in the repulsive forces region where the interaction distance between the two materials is shorter than the normal bonding length. The quantum calculation results agree well with the Wang transition theory. Furthermore, it is also noticed that, due to the wave‐particle duality of electron, electron transfer will obviously occur at the attractive force region when the two contacting materials exhibit a larger work function difference. [ABSTRACT FROM AUTHOR]

Mass transfer is an essential factor determining photocatalytic performance, which can be modulated by fluid field via manipulating the kinetic characteristics of photocatalysts and photocatalytic intermediates. Past decades have witnessed the efforts and achievements made in manipulating mass transfer based on photocatalyst structure and composition design, and thus, a critical survey that scrutinizes the recent progress in this topic is urgently necessitated. This review examines the basic principles of how mass transfer behavior impacts photocatalytic activity accompanying with the discussion on theoretical simulation calculation including fluid flow speed and pattern. Meanwhile, newly emerged viable photocatalytic micro/nanomotors with self‐thermophoresis, self‐diffusiophoresis, and bubble‐propulsion mechanisms as well as magnet‐actuated photocatalytic artificial cilia for facilitating mass transfer will be covered. Furthermore, their applications in photocatalytic hydrogen evolution, carbon dioxide reduction, organic pollution degradation, bacteria disinfection and so forth are scrutinized. Finally, a brief summary and future outlook are presented, providing a viable guideline to those working in photocatalysis, mass transfer, and other related fields. [ABSTRACT FROM AUTHOR]

This study introduces a novel self-powered metamaterial augmented nanogenerator for low-frequency acoustic telecommunication (MANLAT), which is designed to enhance acoustic communication capabilities by utilizing the local resonance mechanism to selectively amplify specific frequency bands of incident sound and generate large amplitude signals in a self-powered manner. The MANLAT device consists of a flexible bottom that responds to pressure differences by generating strong vibrations. Additionally, a lightweight cone-shaped component is attached to the central part of the flexible plate, thus increasing the surface area in that region. Through contact electrification and electrostatic induction mechanisms, a substantial electrical signal is generated, allowing the device to serve as a self-powered acoustic telecommunication receiver. To assess its performance in real-world scenarios, environmental interference was simulated by generating white noise added to the modulated waveform containing information, which was then transmitted through a loudspeaker. At the receiving end, a high-precision microphone sensor was used alongside the MANLAT device to capture the sound wave. The experimental results demonstrate that the MANLAT device surpassed the microphone sensor in mitigating noise interference and enabled the effective decoding of information even in the presence of high levels of white noise or background music. Consequently, the device simplifies communication systems, facilitates reliable and environmentally friendly communication, and enhances information security. [Display omitted] • A self-powered low frequency acoustic telecommunication device is proposed. • The device shows strong anti-interference capability. • Covert communication is demonstrated with background music. [ABSTRACT FROM AUTHOR]

We introduce an innovative designof a disk triboelectric nanogenerator(TENG) with segmental structures for harvesting rotational mechanicalenergy. Based on a cyclic in-plane charge separation between the segmentsthat have distinct triboelectric polarities, the disk TENG generateselectricity with unique characteristics, which have been studied byconjunction of experimental results with finite element calculations.The role played by the segmentation number is studied for maximizingoutput. A distinct relationship between the rotation speed and theelectrical output has been thoroughly investigated, which not onlyshows power enhancement at high speed but also illuminates its potentialapplication as a self-powered angular speed sensor. Owing to the nonintermittentand ultrafast rotation-induced charge transfer, the disk TENG hasbeen demonstrated as an efficient power source for instantaneouslyor even continuously driving electronic devices and/or charging anenergy storage unit. This work presents a novel working mode of TENGsand opens up many potential applications of nanogenerators for harvestingeven large-scale energy. [ABSTRACT FROM AUTHOR]

Aiming at harvesting ambient mechanicalenergy for self-poweredsystems, triboelectric nanogenerators (TENGs) have been recently developedas a highly efficient, cost-effective and robust approach to generateelectricity from mechanical movements and vibrations on the basisof the coupling between triboelectrification and electrostatic induction.However, all of the previously demonstrated TENGs are based on verticalseparation of triboelectric-charged planes, which requires sophisticateddevice structures to ensure enough resilience for the charge separation,otherwise there is no output current. In this paper, we demonstrateda newly designed TENG based on an in-plane charge separation processusing the relative sliding between two contacting surfaces. UsingPolyamide 6,6 (Nylon) and polytetrafluoroethylene (PTFE) films withsurface etched nanowires, the two polymers at the opposite ends ofthe triboelectric series, the newly invented TENG produces an open-circuitvoltage up to ∼1300 V and a short-circuit current density of4.1 mA/m2with a peak power density of 5.3 W/m2, which can be used as a direct power source for instantaneouslydriving hundreds of serially connected light-emitting diodes (LEDs).The working principle and the relationships between electrical outputsand the sliding motion are fully elaborated and systematically studied,providing a new mode of TENGs with diverse applications. Comparedto the existing vertical-touching based TENGs, this planar-slidingTENG has a high efficiency, easy fabrication, and suitability formany types of mechanical triggering. Furthermore, with the relationshipbetween the electrical output and the sliding motion being calibrated,the sliding-based TENG could potentially be used as a self-powereddisplacement/speed/acceleration sensor. [ABSTRACT FROM AUTHOR]

[Display omitted] • A photo-thermal solid slippery surface was successfully fabricated via a facile method. • The as-prepared surface showed good anti-icing and de-icing properties. • The as-prepared surface showed superior stability and self-healing property. Ice formation on the surface of outdoor equipment brings a severe negative impact on daily life and industry production. Lubricant infused surfaces have arisen intensive attentions for anti-icing due to its outstanding water repellency. In this work, a dual-functions anti-icing/de-icing solid slippery surface has been developed by infusion GO@Fe 3 O 4 mixed PDMS/PF lubricant into nano-grass CuO (PSSS). On account of the low surface energy of the lubricant and the photothermal effect of GO@Fe 3 O 4 , ice formation and accumulation can be inhibited and readily in-situ removed. After the addition of GO@Fe 3 O 4 , the icing-delay time of 5% PSSS can prolonged to 269 s under –10 ℃ which is significantly longer than that of bare Cu (6 s) and PDMS/PF infused surface (78 s). The surface temperature can be sharply arisen to 71.7 ℃ under the infrared irradiation within 120 s, the ice and lubricant would be melted under this high temperature and showed an extremely low ice adhesion strength. It was worth noting that the surface can be self-healed within 36 s because of the photothermal effect. Besides, the PSSS could maintain its photothermal effect with ignorable attenuation even after exposed in laboratory environment for 12 months, indicating prominent stability. This work provides a perspective for designing robust lubricant infused slippery surface and will have a profound influence for anti-icing/de-icing applications. [ABSTRACT FROM AUTHOR]

As a versatile two-dimensional (2D) material, graphene has attracted an increasing amount of attention from different fields, e.g., Geim et al. (Science 2019, 363: 145–148) experimentally reported artificial graphene capillaries with a 2D slit of a few angstroms in height, where water fully moves through these capillaries and all salt ions are excluded. To understand the phenomenon observed experimentally, here we systematically investigate hydrodynamic properties of the lamellar graphene channels with different interlayer height, such as self-diffusion, viscosity and permeability of waters. Molecular dynamics simulations show that water viscosity decreases with the increasing of channel height, while the diffusion coefficient and flux of water enhance. For the channel with a height of 0.78 nm, the water permeability is far larger than the values of commercial reverse osmosis membranes, simultaneously exhibiting a salt rejection of >95%. Besides, the simulated results show that the flexible channels initially filled with water will not collapse when the channels are formed by more than two layers of graphene sheets on each side. This work highlights the stability mechanism of the graphene channel, which will show its importance for future development of graphene membranes. [Display omitted] • The mechanism underlying the formation of graphene lamellar channels in experiments without collapse phenomenon is revealed. • The water self-diffusion and viscosity in confined graphene channels are clarified by using molecular dynamics simulation. • A practical strategy to avoid collapse of lamellar channel by using multilayer graphene nanosheet is proposed. • The confined graphene lamellar channel exhibits high water permeability and salt rejection for water desalination. • The optimal interlayer height can be achieved by using monolayer silicene as a spacer. [ABSTRACT FROM AUTHOR]

Abstract: Transparent conductive Al-doped zinc oxide (AZO) films with highly (002)-preferred orientation were deposited on quartz substrates at room temperature by RF magnetron sputtering. Optimization of deposition parameters was based on RF power, Ar pressure in the vacuum chamber, and distance between the target and substrate. The structural, electrical, and optical properties of the AZO thin films were investigated by X-ray diffraction, Hall measurement, and optical transmission spectroscopy. The 250nm thickness AZO films with an electrical resistivity as low as 4.62×10−4 Ωcm and an average optical transmission of 93.7% in the visible range were obtained at RF power of 300W, Ar flow rate of 30sccm, and target distance of 7cm. The optical bandgap depends on the deposition condition, and was in the range of 3.75–3.86eV. These results make the possibility for light emitting diodes (LEDs) and solar cells with AZO films as transparent electrodes, especially using lift-off process to achieve the transparent electrode pattern transfer. [Copyright &y& Elsevier]

Coronavirus disease 2019 (COVID-19) as a severe acute respiratory syndrome infection has spread rapidly across the world since its emergence in 2019 and drastically altered our way of life. Patients who have recovered from COVID-19 may still face persisting respiratory damage from the virus, necessitating long-term supervision after discharge to closely assess pulmonary function during rehabilitation. Therefore, developing portable spirometers for pulmonary function tests is of great significance for convenient home-based monitoring during recovery. Here, we propose a wireless, portable pulmonary function monitor for rehabilitation care after COVID-19. It is composed of a breath-to-electrical (BTE) sensor, a signal processing circuit, and a Bluetooth communication unit. The BTE sensor, with a compact size and light weight of 2.5 cm3 and 1.8 g respectively, is capable of converting respiratory biomechanical motions into considerable electrical signals. The output signal stability is greater than 93% under 35%–81% humidity, which allows for ideal expiration airflow sensing. Through a wireless communication circuit system, the signals can be received by a mobile terminal and processed into important physiological parameters, such as forced expiratory volume in 1 s (FEV 1) and forced vital capacity (FVC). The FEV 1 /FVC ratio is then calculated to further evaluate pulmonary function of testers. Through these measurement methods, the acquired pulmonary function parameters are shown to exhibit high accuracy (>97%) in comparison to a commercial spirometer. The practical design of the self-powered flow spirometer presents a low-cost and convenient method for pulmonary function monitoring during rehabilitation from COVID-19. • We develop a low-cost and convenient method for pulmonary function monitoring during rehabilitation from COVID-19. • It is composed of a lightweight breath-to-electrical sensor, a signal processing circuit, and a Bluetooth communication unit. • The output signal stability is greater than 93% under 35%–81% humidity, which allows for ideal expiration airflow sensing. • A wireless communication system receives signals from a mobile terminal and converts them into pulmonary parameters. • The FEV1/FVC ratio is then calculated to further evaluate pulmonary function of testers with high accuracy of >97%. [ABSTRACT FROM AUTHOR]