RESUMO
Perovskite solar cells (PSCs) have rapidly become a prevalent photovoltaic technology owing to their simple structure, low processing cost, and remarkable increase in solar-to-electric power conversion efficiency (PCE). However, the intermittent nature of solar radiation induces some technical and financial challenges for its practical applications as a reliable power source. To address this issue, the integration of PSCs with supercapacitors (SCs) in the form of integrated photo-supercapacitors (IPSs) has gathered significant attention. This integration can balance energy availability and demand, reduce energy wastage, and stabilize power output for portable and wearable electronics. Meanwhile, the excellent optoelectronic properties with mixed electronic and ionic conductivity of metal halide perovskites (MHPs) have expanded their application as electrode and electrolyte materials for SCs and photo-supercapacitors (PSs) applications. This review provides an all-inclusive summary of the current state-of-the-art research progress of PSCs-IPSs and MHPs-based SCs and PSs by highlighting their basics and integration approaches. It also discusses the challenges and prospects of these materials and technologies.
RESUMO
A superconducting quantum magnetometer for high-sensitivity applications has been developed by exploiting the flux focusing of the superconducting loop. Unlike conventional dc SQUID magnetometers that use a superconducting flux transformer or a multiloop design, in this case, a very simple design has been employed. It consists of a bare dc SQUID with a large washer-shaped superconducting ring in order to guarantee a magnetic field sensitivity BΦ less than one nT/Φ0. The degradation of the characteristics of the device due to an inevitable high value of the inductance parameter ßL was successfully compensated by damping the inductance of the dc SQUID. The size of the magnetometer, coinciding with that of the washer, is 5 × 5 mm2 and the spectral density of the magnetic field noise is 8 fT/âHz with a low frequency noise knee of two Hz. The excellent performance of this simple magnetometer makes it usable for all high-sensitivity applications including magnetoencephalography.
RESUMO
In the present article, experimental results regarding fully integrated superconducting quantum interference devices (SQUID), including a circuit to tune and optimize the main sensor device characteristics, are reported. We show the possibility of modifying the critical current of a SQUID magnetometer in liquid helium by means of a suitable heating circuit. This allows us to improve the characteristics of the SQUID sensor and in particular to optimize the voltage-magnetic flux characteristic and the relative transfer factor (responsivity) and consequently to also improve the flux and magnetic field noise. It is also possible to reset the SQUID sensor in case of entrapment of magnetic flux, avoiding taking it out of the helium bath. These results are very useful in view of most SQUID applications such as those requiring large multichannel systems in which it is desirable to optimize and eventually reset the magnetic sensors in a simple and effective way.
RESUMO
Decentralized treatment of wastewater in rural areas usually has several challenges, which include large fluctuations in pollutant concentration and water quantity, complicated operation and maintenance of conventional biochemical treatment equipment, resulting in poor stability and a low compliance rate of the wastewater treatment process. In order to solve the above problems, a new integration reactor is designed, which uses gravity and aeration tail gas self-reflux technology to realize the reflux of sludge and the nitrification liquid, respectively. The feasibility and operation characteristics of its application for decentralized wastewater treatment in rural areas are explored. The results demonstrated that, under constant influent, the device showed strong tolerance to the shock of pollutant load. The chemical oxygen demand, NH4+-N, total nitrogen and total phosphorus fluctuated in the ranges of 95-715 mg/L, 7.6-38.5 mg/L, 9.32-40.3 mg/L and 0.84-4.9 mg/L, respectively. The corresponding effluent compliance rates were 82.1%, 92.8%, 96.4% and 96.3%, respectively. When the wastewater discharge was non-constant and the maximum single-day Qmax/Qmin reached 5, all indicators of the effluent met the relevant discharge standard. The integrated device also demonstrated high phosphorus enrichment levels in its anaerobic zone; the concentration of phosphorus reached a maximum of 26.9 mg/L, which created a good environment for phosphorus removal. The microbial community analysis showed that sludge digestion, denitrification, and phosphorus-accumulating bacteria all played an important role in pollutant treatment.
Assuntos
Líquidos Corporais , Poluentes Ambientais , Águas Residuárias , Esgotos , FósforoRESUMO
Biosensing technologies are required for point-of-care testing (POCT). We determine some physical parameters such as molecular charge and mass, redox potential, and reflective index for measuring biological phenomena. Among such technologies, biologically coupled gate field-effect transistor (Bio-FET) sensors are a promising candidate as a type of potentiometric biosensor for the POCT because they enable the direct detection of ionic and biomolecular charges in a miniaturized device. However, we need to reconsider some technical issues of Bio-FET sensors to expand their possible use for biosensing in the future. In this perspective, the technical issues of Bio-FET sensors are pointed out, focusing on the shielding effect, pH signals, and unique parameters of FETs for biosensing. Moreover, other attractive features of Bio-FET sensors are described in this perspective, such as the integration and the semiconductive materials used for the Bio-FET sensors.
Assuntos
Técnicas Biossensoriais , Transistores Eletrônicos , ÍonsRESUMO
On-chip generation of pressure gradients via electrokinetic means can offer several advantages to microfluidic assay design and operation in a variety of applications. In this article, we describe a simple approach to realizing this capability by employing a polyacrylamide-based gel structure fabricated within a fluid reservoir located at the terminating end of a microchannel. Application of an electric field across this membrane has been shown to block a majority of the electroosmotic flow generated within the open duct yielding a high pressure at the channel-membrane junction. Experiments show the realization of higher pressure-driven velocities in an electric field-free separation channel integrated to the micropump with this design compared to other similar micropumps described in the literature. In addition, the noted velocity was found to be less sensitive to the extent of Debye layer overlap in the channel network, and therefore more impressive when working with background electrolytes having higher ionic strengths. With the current system, pressure-driven velocities up to 3.6 mm/s were realized in a 300-nm-deep separation channel applying a maximum voltage of 3 kV at a channel terminal. To demonstrate the separative performance of our device, a nanofluidic pressure-driven ion-chromatographic analysis was subsequently implemented that relied on the slower migration of cationic analytes relative to the neutral and anionic ones in the separation channel likely due to their strong electrostatic interaction with the channel surface charges. A mixture of amino acids was thus separated with resolutions greater than those reported by our group for a similar analysis previously.
Assuntos
Géis/química , Membranas Artificiais , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Aminoácidos/isolamento & purificação , Cromatografia por Troca Iônica/instrumentação , Desenho de Equipamento , Nanotecnologia/instrumentação , PressãoRESUMO
BACKGROUND: Ion beam therapy allows for a substantial sparing of normal tissues and higher biological efficacy. Synthetic single crystal diamond is a very good material to produce high-spatial-resolution and highly radiation hard detectors for both dosimetry and microdosimetry in ion beam therapy. PURPOSE: The aim of this work is the design, fabrication and test of an integrated waterproof detector based on synthetic single crystal diamond able to simultaneously perform dosimetric and microdosimetric characterization of clinical ion beams. METHODS: The active elements of the integrated diamond device, that is, dosimeter and microdosimeter, were both realized in a Schottky diode configuration featured by different area, thickness, and shape by means of photolithography technologies for the selective growth of intrinsic and boron-doped CVD diamond. The cross-section of the sensitive volume of the dosimetric element is 4 mm2 and 1 µm-thick, while the microdosimetric one has an active cross-sectional area of 100 × 100 µm2 and a thickness of about 6.2 µm. The dosimetric and microdosimetric performance of the developed device was assessed at different depths in a water phantom at the MedAustron ion beam therapy facility using a monoenergetic uniformly scanned carbon ion beam of 284.7 MeV/u and proton beam of 148.7 MeV. The particle flux in the region of the microdosimeter was 6·107 cm2 /s for both irradiation fields. At each depth, dose and dose distributions in lineal energy were measured simultaneously and the dose mean lineal energy values were then calculated. Monte Carlo simulations were also carried out by using the GATE-Geant4 code to evaluate the relative dose, dose averaged linear energy transfer (LETd ), and microdosimetric spectra at various depths in water for the radiation fields used, by considering the contribution from the secondary particles generated in the ion interaction processes as well. RESULTS: Dosimetric and microdosimetric quantities were measured by the developed prototype with relatively low noise (â¼2 keV/µm). A good agreement between the measured and simulated dose profiles was found, with discrepancies in the peak to plateau ratio of about 3% and 4% for proton and carbon ion beams respectively, showing a negligible LET dependence of the dosimetric element of the device. The microdosimetric spectra were validated with Monte Carlo simulations and a good agreement between the spectra shapes and positions was found. Dose mean lineal energy values were found to be in close agreement with those reported in the literature for clinical ion beams, showing a sharp increase along the Bragg curve, being also consistent with the calculated LETd for all depths within the experimental error of 10%. CONCLUSIONS: The experimental indicate that the proposed device can allow enhanced dosimetry in particle therapy centers, where the absorbed dose measurement is implemented by the microdosimetric characterization of the radiation field, thus providing complementary results. In addition, the proposed device allows for the reduction of the experimental uncertainties associated with detector positioning and could facilitate the partial overcoming of some drawbacks related to the low sensitivity of diamond microdosimeters to low LET radiation.
Assuntos
Diamante , Prótons , Diamante/química , Radiometria , Carbono/uso terapêutico , Íons , Método de Monte Carlo , ÁguaRESUMO
Phosphorene, or two-dimensional (2D) black phosphorus, has recently emerged as a competitor of graphene as it offers several advantages, including a tunable band gap, higher on/off current ratio, piezoelectric nature, and biocompatibility. Researchers have succeeded in obtaining several forms of phosphorene, such as nanosheets, nanorods, nanoribbons, and quantum dots, with satisfactory yields. Nanostructures with various controlled properties have been fabricated in multiple devices for energy production. These phosphorene-based devices are lightweight, flexible, and efficient, demonstrating great potential for energy-harvesting applications in sensors and nanogenerators. While ongoing exploration and advancements continue for these lightweight energy harvesters, it is essential to review the current progress in order to develop a future roadmap for the potential use of these phosphorene-based energy harvesters in space programs. They could be employed in applications such as wearable devices for astronauts, where ultralow weight is a vital component of any integrated device. This review also anticipates the growing significance of phosphorene in various emerging applications such as robots, information storage devices, and artificial intelligence.
RESUMO
BACKGROUND: The monkeypox virus (MPXV) is a linear double-stranded DNA virus with a large genome that causes tens of thousands of infections and hundreds of deaths in at least 40 countries and regions worldwide. Therefore, timely and accurate diagnostic testing could be an important measure to prevent the ongoing spread of MPXV and widespread epidemics. RESULTS: Here, we designed multiple sets of primers for the target region of MPXV for loop-mediated isothermal amplification (LAMP) detection and identified the optimal primer set. Then, the specificity in fluorescent LAMP detection was verified using the plasmids containing the target gene, pseudovirus and other DNA/RNA viruses. We also evaluated the sensitivity of the colorimetric LAMP detection system using the plasmid and pseudovirus samples, respectively. Besides, we used monkeypox pseudovirus to simulate real samples for detection. Subsequent to the establishment and introduction of a magnetic beads (MBs)-based nucleic acid extraction technique, an integrated device was developed, characterized by rapidity, high sensitivity, and remarkable specificity. This portable system demonstrated a visual detection limit of 137 copies/mL, achieving sample-to-answer detection within 1 h. SIGNIFICANCE: The device has the advantages of integration, simplicity, miniaturization, and visualization, which help promote the realization of accurate, rapid, portable, and low-cost testing. Meanwhile, this platform could facilitate efficient, cost-effective and easy-operable point-of-care testing (POCT) in diverse resource-limited settings in addition to the laboratory.
Assuntos
Colorimetria , Monkeypox virus , Técnicas de Amplificação de Ácido Nucleico , Colorimetria/métodos , Colorimetria/instrumentação , Técnicas de Amplificação de Ácido Nucleico/métodos , Monkeypox virus/genética , Monkeypox virus/isolamento & purificação , Limite de Detecção , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/instrumentaçãoRESUMO
BACKGROUND: Solar cell/supercapacitor integrated devices (SCSD) have made some progress in terms of device structure and electrode materials, but there are still many key challenges in controlling electrode performance and improving the efficiency of integrated devices. AIM OF REVIEW: It is necessary to study how to balance the photoelectric conversion process and the storage process. From the microscopic mechanism of different functional unit materials to the mechanism of macroscopic devices, it is essential to conduct in-depth research. KEY SCIENTIFIC CONCEPTS OF REVIEW: Here, the structures and preparation methods of various types of integrated SCSD were introduced. Then, the strategies for improving the overall performance of integrated devices were evaluated. Finally, the key objectives of reducing the cost of materials, increasing the stability and sustainability of devices were highlighted. Better matching of different functional units of devices was also prospected.
RESUMO
Most chemical sensing scenarios require the selective and simultaneous determination of the concentrations of multiple gas species. In order to enable large-scale monitoring, reliability, robustness, and the potential for integration and miniaturization are key parameters that next-generation sensing technologies must comply with. Due to their superior sensitivity and selectivity as compared to standard NDIR-type systems, photoacoustic NDIR-approaches offer a means for selective detection at much reduced system dimensions such that microintegration becomes feasible. This contribution presents an acoustic frequency multiplexing method to integrate sensing capabilities for the parallel analysis of multiple gases in a single device without loss in selectivity via sound frequency separation. The approach is demonstrated using mid-infrared light emitting diodes and a multigas photoacoustic detector to monitor some of the most important greenhouse gases: carbon dioxide and methane. The number of gas species the sensor concept is able to detect simultaneously can be expanded without increasing the size of the system or its complexity. Additionally, the results demonstrate that the integrated device features the same selectivity and sensitivity as the currently used single gas photoacoustic NDIR systems. Furthermore, the possibility of an extension to any number of gas species is argued.
Assuntos
Dióxido de Carbono , Gases , Reprodutibilidade dos Testes , Espectrofotometria Infravermelho/métodos , Gases/análise , Dióxido de Carbono/análiseRESUMO
Photovoltaic cells (PVs) are able to convert solar energy to electric energy, while energy storage devices are required to be equipped due to the fluctuations of sunlight. However, the electrical connection of PVs and energy storage devices leads to increased energy consumption, and thus energy storage ability and utilization efficiency are decreased. One of the solutions is to explore an integrated photoelectrochemical energy conversion-storage device. Up to date, the integrated photo-rechargeable Li-ion batteries often suffer from unstable photo-active materials and flammable electrolytes under illumination, with concerns in safety risks and limited lifetime. To address the critical issues, here a novel photo-rechargeable aluminum battery (PRAB) is designed with safe ionic liquid electrolytes and stable polyaniline photo-electrodes. The integrated PRAB presents stable operation with an enhanced reversible specific capacity ≈191% under illumination. Meanwhile, a simplified continuum model is established to provide rational guidance for designing electrode structures along with a charging/discharging strategy to meet the practical operation conditions. The as-designed PRAB presents an energy-saving efficiency ≈61.92% upon charging and an energy output increment ≈31.25% during discharging under illumination. The strategy of designing and fabricating stable and safe photo-rechargeable non-aqueous Al batteries highlights the pathway for substantially promoting the utilization efficiency of solar energy.
RESUMO
In conventional photo-thermal-electric conversion systems, the photo-thermal conversion module is coupled to a thermoelectric conversion module. However, the physical contact interface between the modules causes serious energy loss. In order to solve this problem, a novel photo-thermal-electric conversion system with an integrated support material has been developed, with a photo-thermal conversion component at the top, an inside thermoelectric conversion component, and a cooling component at the bottom, surrounded by a water conduction component. The supporting materials of each part are polydimethylsiloxane (PDMS), and there is no apparent physical interface between each part. This integrated support material reduces the heat loss caused by the mechanically coupled interfaces in traditional components. In addition, the confined edge 2D water transport path effectively reduces the heat loss due to water convection. Under 1 sun irradiation, the water evaporation rate and open-circuit voltage of the integrated system reach 2.46 kg m-2 h-1 and 30 mV, respectively, and are nearly 1.4 times and 5.8 times higher than those of non-integrated systems.
RESUMO
Fiber-shaped photodetectors (FPDs) have attracted special attention to wearable health monitoring due to their 3D absorption capabilities. However, the practical application of traditional FPDs is severely limited by the irreversible degradation of performance caused by vulnerable interface compatibility on complex deformation and a single function. Here, an integrated photoelectrochemical FPD/battery device (FPDB) is designed, consisting of a common electrode, photoanode, anode, and sol-gel electrolyte as an isolation layer, which not only effectively avoids the short circuit problem of FPD but also endows high-efficiency energy storage capacity. As expected, the resulting all-in-one triple-twisted fiber-shaped FPDB simultaneously achieves high responsiveness of 151.45 mA W-1 and excellent volume capacity of 18.75 mAh cm-3. Such a stable architectural design and multifunctional integration of functional fibers accelerate the development of next-generation wearable fabrics.
RESUMO
The architecture of integrated perovskite/organic solar cells (IPOSCs) is a promising strategy to further enhance the power conversion efficiency (PCE) by extending their photoresponse to the near-infrared range. To maximize the potential benefits of the system, it is crucial to optimize the perovskite crystallinity and intimate morphology of the organic bulk heterojunction (BHJ). More importantly, efficient charge transfer between the interface of the perovskite and BHJ plays a key role in the success of IPOSCs. This paper reports efficient IPOSCs by forming interdigitated interfaces between the perovskite and BHJ layers. Large microscale perovskite grains enable the infiltration of BHJ materials into the perovskite grain boundary, thereby increasing the interface area and promoting efficient charge transfer. Owing to the synergetic effect of the interdigitated interfaces and optimized BHJ nanomorphology, the developed P-I-N-type IPOSC exhibited an excellent PCE of 18.43% with a Jsc of 24.44 mA/cm2, a Voc of 0.95 V, and a FF of 79.49%, which is one of very efficient hybrid perovskite-polymer solar cells.
RESUMO
In this work, a redox-graphene (Rx-Gr) film with electron-mediating ability has been integrated into a modular flexible pocket device, giving rise to a reusable biosensing platform. The Rx-Gr has been obtained in water from graphite taking advantage of catechin, a redox-antioxidant, able to assist the sonochemical layered-material exfoliation, conferring electron mediating feature. A film composed exclusively of Rx-Gr has been transferred via thermal rolling onto a flexible PET-support that was used as the biosensor base. The biosensing platform, composed of office-grade materials, was then fabricated using a cutter-plotter and assembled by thermal lamination; an interchangeable paper-based strip was used to host the enzymatic reaction and drive the capillary flow. An acetylcholinesterase-based inhibition assay has been optimized onboard the pocket device to determine chlorpyriphos, a widespread environmental pesticide. The proposed set-up allows the determination of chlorpyriphos at low overpotential (0.2 V) with satisfactory sensitivity (LOD = 0.2 ppb), thanks to the straightforward electroactivity of the Rx-Gr film towards thiocholine (enzymatic product). The modular design allows 5 consecutive complete inhibition assays (control + inhibition measure) retaining the performance (RSD = 5.4%; n = 5). The coupling of bench-top technologies and a new functional graphene film resulted in the development of a cost-effective, reusable, transportable, and within everyone's reach biosensing platform.
Assuntos
Técnicas Biossensoriais , Clorpirifos , Grafite , Praguicidas , Acetilcolinesterase , Técnicas EletroquímicasRESUMO
Simultaneous monitoring of electrophysiological and biochemical signals is of great importance in healthcare and fitness management, while the fabrication of highly integrated and flexible devices is crucial to these applications. Herein, we devised a multifunctional and flexible hydrogel-paper patch (HPP) that was capable of simultaneously real-time monitoring of electrocardiogram (ECG) signal and biochemical signal (glucose content) in sweat during exercise. The self-assembly of the highly porous PEDOT:PSS hydrogel on paper fiber provided the HPP with good conductivity and hydrophilic wettability for efficient electron transmission and substance diffusion, thereby enabling it to serve as a low-impedance ECG electrode and a highly sensitive glucose sensor. Additionally, the spontaneous capillary flow effect allows the paper patch to be used as microfluidic channels for the collect and analysis of sweat. Moreover, the HPP is integrated with a flexible printed circuit board (FPCB) and works as a multifunctional wearable device mounted on the chest for real-time monitoring of electrophysiological and biochemical signals during exercise.
Assuntos
Técnicas Biossensoriais , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Hidrogéis , SuorRESUMO
A design integrating multiple cladding mode strippers used in fiber laser architectures into a single device is proposed. This approach can increase the compactness of fiber lasers, thus contributing to industrial laser processing applications. By offset-placing the most intense light-stripping parts, for instance, by inversing the laser injection directions or by displacing the beginning of etched sections, multiple cladding mode strippers bundled together into a single housing can have the hottest regions separated and can operate at full power simultaneously, with no evident cross-influence on each other. Two and three cladding-mode-stripper arrays have been implemented, and validation tests have been conducted with ~500-W cladding power being injected into each input port. For both arrayed devices, compared to the scenario in which only a single cladding mode stripper is working, no greater than a 2.1 °C temperature increment is generated when all components are operating concurrently, which demonstrates the effectiveness of the integration method. In this way, one half and two thirds of space/weight reduction can be realized, respectively, for the two and three cladding-mode-stripper arrays, which is meaningful, since cladding mode strippers are among the most bulky and hottest components in fiber lasers. Moreover, this integration provides a valuable reference for the miniaturization of other components, and thus, could contribute to the development fiber lasers with higher power-to-volume ratios, which would be more economical for industrial applications.
RESUMO
The rapid development of portable and wearable electronics has promoted the integration of multifunction techniques. Although flexible energy storage systems have been successfully investigated, the compact configuration with photodetector and energy storage components has received less attention. As a new member of the 2D material class, MXene exhibits remarkable electronic and optical properties. Here, through the intentional introduction of ZIF-67 derivatives deposited on the Mo2CTx nanosheets, the synthesized Co-CoOx/NC/Mo2CTx heterostructure not only provided a straightforward pathway for photogenerated electrons to transport but also enhanced the structural stability of Mo2CTx, leading to a high responsivity and short rise/decay time under the illumination of simulated light in the photoelectrochemical (PEC) configuration. The integrated flexible device based on a zinc ion battery and Co-CoOx/NC/Mo2CTx heterostructure shows outstanding photodetection function and retains the intrinsic charge/discharge behaviors, which could monitor 1 day sunlight changes in real time. The paradigm presented here paves the way for realizing the development of miniaturization and multifunction toward next-generation portable and wearable technologies.
RESUMO
An integrated device capable of generating large number of multiplexed optical vortex beams with arbitrary topological charge is considered as one of the crucial requirement for driving information photonics forward. Here we report a simple method for simultaneous generation of 100 multiplexed optical vortex beams from a polymer film of size 1 mm2 and thickness of 30 µm. This is achieved through a combination of computer-generated holography, digital hologram printing and photoisomeric polymers. When the fabricated sample is illuminated with a collimated laser beam, a pre-determined vortex array with arbitrary topological charge is emitted. The polymer film easy to synthesize and exhibits a diffraction efficiency of 30% with a retention period longer than 50 days.