Investigations on the high performance of InGaN red micro-LEDs with single quantum well for visible light communication applications.

In this study, we have demonstrated the potential of InGaN-based red micro-LEDs with single quantum well (SQW) structure for visible light communication applications. Our findings indicate the SQW sample has a better crystal quality, with high-purity emission, a narrower full width at half maximum, and higher internal quantum efficiency, compared to InGaN red micro-LED with a double quantum wells (DQWs) structure. The InGaN red micro-LED with SQW structure exhibits a higher maximum external quantum efficiency of 5.95% and experiences less blueshift as the current density increases when compared to the DQWs device. Furthermore, the SQW device has a superior modulation bandwidth of 424 MHz with a data transmission rate of 800 Mbit/s at an injection current density of 2000 A/cm2. These results demonstrate that InGaN-based SQW red micro-LEDs hold great promise for realizing full-color micro-display and visible light communication applications.

Phase/Interfacial-Engineered Two-Dimensional-Layered WSe2 Films by a Plasma-Assisted Selenization Process: Modulation of Oxygen Vacancies in Resistive Random-Access Memory.

Here, we propose phase and interfacial engineering by inserting a functional WO3 layer and selenized it to achieve a 2D-layered WSe2/WO3 heterolayer structure by a plasma-assisted selenization process. The 2D-layered WSe2/WO3 heterolayer was coupled with an Al2O3 film as a resistive switching (RS) layer to form a hybrid structure, with which Pt and W films were used as the top and bottom electrodes, respectively. The device with good uniformity in SET/RESET voltage and high low-/high-resistance window can be obtained by controlling a conversion ratio from a WO3 film to a 2D-layered WSe2 thin film. The Pt/Al2O3/(2D-layered WSe2/WO3)/W structure shows remarkable improvement to the pristine Pt/Al2O3/W and Pt/Al2O3/2D-layered WO3/W in terms of low SET/RESET voltage variability (-20/20)%, multilevel characteristics (uniform LRS/HRS distribution), high on/off ratio (104-105), and retention (∼105 s). The thickness of the obtained WSe2 was tuned at different gas ratios to optimize different 2D-layered WSe2/WO3 (%) ratios, showing a distinctive trend of reduced and uniform SET/RESET voltage variability as 2D-layered WSe2/WO3 (%) changes from 90/10 (%) to 45/55 (%), respectively. The electrical measurements confirm the superior ability of the metallic 1T phase of the 2D-layered WSe2 over the semiconducting 2H phase. Through systemic studies of RS behaviors on the effect of 1T/2H phases and 2D-layered WSe2/WO3 ratios, the low-temperature plasma-assisted selenization offers compatibility with the temperature-limited 3D integration process and also provides much better thickness control over a large area.

Synthesis of Nano-Structured Ge as Transmissive or Reflective Saturable Absorber for Mode-Locked Fiber Laser.

Amorphous-Ge (α-Ge) or free-standing nanoparticles (NPs) synthesized via hydrogen-free plasma-enhanced chemical vapor deposition (PECVD) were applied as transmissive or reflective saturable absorbers, respectively, for starting up passively mode-locked erbium-doped fiber lasers (EDFLs). Under a threshold pumping power of 41 mW for mode-locking the EDFL, the transmissive α-Ge film could serve as a saturable absorber with a modulation depth of 52-58%, self-starting EDFL pulsation with a pulsewidth of approximately 700 fs. Under a high power of 155 mW, the pulsewidth of the EDFL mode-locked by the 15 s-grown α-Ge was suppressed to 290 fs, with a corresponding spectral linewidth of 8.95 nm due to the soliton compression induced by intra-cavity self-phase modulation. The Ge-NP-on-Au (Ge-NP/Au) films could also serve as a reflective-type saturable absorber to passively mode-lock the EDFL with a broadened pulsewidth of 3.7-3.9 ps under a high-gain operation with 250 mW pumping power. The reflection-type Ge-NP/Au film was an imperfect mode-locker, owing to their strong surface-scattered deflection in the near-infrared wavelength region. From the abovementioned results, both ultra-thin α-Ge film and free-standing Ge NP exhibit potential as transmissive and reflective saturable absorbers, respectively, for ultrafast fiber lasers.

Artificial Leaf for Solar-Driven Ammonia Conversion at Milligram-Scale Using Triple Junction III-V Photoelectrode.

Developing a green and energy-saving alternative to the traditional Haber-Bosch process for converting nitrogen into ammonia is urgently needed. Imitating from biological nitrogen fixation and photosynthesis processes, this work develops a monolithic artificial leaf based on triple junction (3J) InGaP/GaAs/Ge cell for solar-driven ammonia conversion under ambient conditions. A gold layer serves as the catalytic site for nitrogen fixation with photogenerated electrons. The Au/Ti/3J InGaP/GaAs/Ge photoelectrochemical (PEC) device achieves high ammonia production rates and Faradaic efficiencies in a two-electrode system without applying external potential. For example, at 0.2 sunlight intensity, the solar-to-ammonia (STA) conversion efficiency reaches 1.11% and the corresponding Faradaic efficiency is up to 28.9%. By integrating a Ni foil on the anode side for the oxygen evolution reaction (OER), the monolithic artificial leaf exhibits an ammonia production rate of 8.5 µg cm-2 h at 1.5 sunlight intensity. Additionally, a 3 × 3 cm unassisted wireless PEC device is fabricated that produces 1.0039 mg of ammonia in the 36-h durability test. Thus, the new artificial leaf can successfully and directly convert solar energy into chemical energy and generate useful products in an environmentally friendly approach.

Light-Induced Bipolar Photoresponse with Amplified Photocurrents in an Electrolyte-Assisted Bipolar p-n Junction.

The p-n junction with bipolar characteristics sets the fundamental unit to build electronics while its unique rectification behavior constrains the degree of carrier tunability for expanded functionalities. Herein, a bipolar-junction photoelectrode employed with a gallium nitride (GaN) p-n homojunction nanowire array that operates in electrolyte is reported, demonstrating bipolar photoresponse controlled by different wavelengths of light. Significantly, with rational decoration of a ruthenium oxides (RuOx ) layer on nanowires guided by theoretical modeling, the resulting RuOx /p-n GaN photoelectrode exhibits unambiguously boosted bipolar photoresponse by an enhancement of 775% and 3000% for positive and negative photocurrents, respectively, compared to the pristine nanowires. The loading of the RuOx layer on nanowire surface optimizes surface band bending, which facilitates charge transfer across the GaN/electrolyte interface, meanwhile promoting the efficiency of redox reaction for both hydrogen evolution reaction and oxygen evolution reaction which corresponds to the negative and positive photocurrents, respectively. Finally, a dual-channel optical communication system incorporated with such photoelectrode is constructed with using only one photoelectrode to decode dual-band signals with encrypted property. The proposed bipolar device architecture presents a viable route to manipulate the carrier dynamics for the development of a plethora of multifunctional optoelectronic devices for future sensing, communication, and imaging systems.

Piezoelectricity-modulated optical recombination dynamics of monolayer-MoS2/GaN-film heterostructures.

Dynamic manipulation of optoelectronic responses by mechanical stimuli is promising for developing wearable electronics and human-machine interfacing. Although 2D-3D hybrid heterostructures can bring advancements in optoelectronics, their dynamic optical responses to external strains remain rarely studied. Here, we demonstrate the strain-tuned recombination dynamics of monolayer-MoS2 and thin-film-GaN heterostructures. We find that optical excitons in the heterostructures, apart from trions, can be markedly modulated by strains. We argue that MoS2 piezoelectric dipoles across the interfaces lead to curved band diagrams, in which optical excitons dissociate into spatially separated quasi-particles and concurrently relocate to the maxima of valence bands and the minima of conduction bands. With the increase in tensile strains, the photoluminescence (PL) intensity of the heterostructures shows quenched responses. Noticeably, the change in PL spectra strongly depends on the directions of the applied strains because of the lateral piezoelectric periodicity of MoS2 flakes. This work not only helps in understanding the underlying physics of the decreased PL intensities upon applying strains but also demonstrates a feasible way (i.e., strains) to manipulate the PL efficiency of 2D-material-based optoelectronics.

A non-enzymatic, biocompatible electrochemical sensor based on N-doped graphene quantum dot-incorporated SnS2 nanosheets for in situ monitoring of hydrogen peroxide in breast cancer cells.

The current study reports the design and construction of enzyme-free sensor using N-doped graphene quantum dots (N-GQDs)-decorated tin sulfide nanosheets (SnS2) for in situ monitoring of H2O2 secreted by human breast cancer cells. N-GQDs nanoparticles having a size of less than 1 nm were incorporated into SnS2 nanosheets to form an N-GQDs@SnS2 nanocomposite using a simple hydrothermal approach. The resulting hybrid material was an excellent electrocatalyst for the reduction of H2O2, owing to the combined properties of highly conductive N-GQDs and SnS2 nanosheets. The N-GQDs@SnS2-based sensing platform demonstrated substantial sensing ability, with a detection range of 0.0125-1128 µM and a limit of detection of 0.009 µM (S/N = 3). The sensing performance of N-GQDs@SnS2 was highly stable, selective, and reproducible. The practical application of the N-GQDs@SnS2 sensor was successfully demonstrated by quantifying H2O2 in lens cleaner, human urine, and saliva samples. Finally, the N-GQDs@SnS2 electrode was successfully applied for the real-time monitoring of H2O2 released from breast cancer cells and mouse fibroblasts. This study paves the way to designing efficient non-enzymatic electrochemical sensors for various biomolecule detection using a simple method.

A Sandwich-Type Electrochemical Immunosensor for Insulin Detection Based on Au-Adhered Cu5 Zn8 Hollow Porous Carbon Nanocubes and AuNP Deposited Nitrogen-Doped Holey Graphene.

Rapid, accurate, and sensitive insulin detection is crucial for managing and treating diabetes. A simple sandwich-type electrochemical immunosensor is engineered using gold nanoparticle (AuNP)-adhered metal-organic framework-derived copper-zinc hollow porous carbon nanocubes (Au@Cu5 Zn8 /HPCNC) and AuNP-deposited nitrogen-doped holey graphene (NHG) are used as a dual functional label and sensing platform. The results show that identical morphology and size of Au@Cu5 Zn8 /HPCNC enhance the electrocatalytic active sites, conductivity, and surface area to immobilize the detection antibodies (Ab2 ). In addition, AuNP/NHG has the requisite biocompatibility and electrical conductivity, which facilitates electron transport and increases the surface area of the capture antibody (Ab1 ). Significantly, Cu5 Zn8 /HPCNC exhibits necessary catalytic activity and sensitivity for the electrochemical reduction of H2 O2 using (i-t) amperometry and improves the electrochemical response in differential pulse voltammetry. Under optimal conditions, the immunosensor for insulin demonstrates a wide linear range with a low detection limit and viable specificity, stability, and reproducibility. The platform's practicality is evaluated by detecting insulin in human serum samples. All these characteristics indicate that the Cu5 Zn8 /HPCNC-based biosensing strategy may be used for the point-of-care assay of diverse biomarkers.

Observation of polarity-switchable photoconductivity in III-nitride/MoSx core-shell nanowires.

III-V semiconductor nanowires are indispensable building blocks for nanoscale electronic and optoelectronic devices. However, solely relying on their intrinsic physical and material properties sometimes limits device functionalities to meet the increasing demands in versatile and complex electronic world. By leveraging the distinctive nature of the one-dimensional geometry and large surface-to-volume ratio of the nanowires, new properties can be attained through monolithic integration of conventional nanowires with other easy-synthesized functional materials. Herein, we combine high-crystal-quality III-nitride nanowires with amorphous molybdenum sulfides (a-MoSx) to construct III-nitride/a-MoSx core-shell nanostructures. Upon light illumination, such nanostructures exhibit striking spectrally distinctive photodetection characteristic in photoelectrochemical environment, demonstrating a negative photoresponsivity of -100.42 mA W-1 under 254 nm illumination, and a positive photoresponsivity of 29.5 mA W-1 under 365 nm illumination. Density functional theory calculations reveal that the successful surface modification of the nanowires via a-MoSx decoration accelerates the reaction process at the electrolyte/nanowire interface, leading to the generation of opposite photocurrent signals under different photon illumination. Most importantly, such polarity-switchable photoconductivity can be further tuned for multiple wavelength bands photodetection by simply adjusting the surrounding environment and/or tailoring the nanowire composition, showing great promise to build light-wavelength controllable sensing devices in the future.

Flexible 2D Cu Metal: Organic Framework@MXene Film Electrode with Excellent Durability for Highly Selective Electrocatalytic NH3 Synthesis.

Electrocatalytic nitrate reduction to ammonia (ENRA) is an effective strategy to resolve environmental and energy crisis, but there are still great challenges to achieve high activity and stability synergistically for practical application in a fluid environment. The flexible film electrode may solve the abovementioned problem of practical catalytic application owing to the advantages of low cost, light weight, eco-friendliness, simple and scalable fabrication, extensive structural stability, and electrocatalytic reliability. Herein, 2D hybridization copper 1,4-benzenedi-carboxylate (CuBDC) has been grown on electronegative MXene nanosheets (Ti3C2Tx) seamlessly to prepare a 2D flexible CuBDC@Ti3C2Tx electrode for ENRA. The flexible electrode simultaneously exhibits high Faradaic efficiency (86.5%) and excellent stability for NH3 synthesis, which are comparable to previously reported nanomaterials toward ENRA. Especially, the flexible electrode maintains outstanding FE NH3 toward ENRA after the bending, twisting, folding, and crumpling tests, indicating excellent electroconductibility, high stability, and durability. This work not only provides mild permeation-mediated strategy to fabricate a flexible electrode but also explores the practical applications of the electrode with effectively environmental adaptability in solving global environmental contamination and energy crisis by effective ENRA.

MOF-Derived Cu-BTC Nanowire-Embedded 2D Leaf-like Structured ZIF Composite-Based Aptamer Sensors for Real-Time In Vivo Insulin Monitoring.

Insulin, which is a hormone produced by the ß-cells of the pancreas, regulates the glucose levels in the blood and can transport glucose into cells to produce glycogen or triglycerides. Insulin deficiency can lead to hyperglycemia and diabetes. Therefore, insulin detection is critical in clinical diagnosis. In this study, disposable Au electrodes were modified with copper(II) benzene-1,3,5-tricarboxylate (Cu-BTC)/leaf-like zeolitic imidazolate framework (ZIF-L) for insulin detection. The aptamers are easily immobilized on the Cu-BTC/ZIF-L composite by physical adsorption and facilitated the specific interaction between aptamers and insulin. The Cu-BTC/ZIF-L composite-based aptasensor presented a wide linear insulin detection range (0.1 pM to 5 µM) and a low limit of detection of 0.027 pM. In addition, the aptasensor displayed high specificity, good reproducibility and stability, and favorable practicability in human serum samples. For the in vivo tests, Cu-BTC/ZIF-L composite-modified electrodes were implanted in non-diabetic and diabetic mice, and insulin was quantified using electrochemical and enzyme-linked immunosorbent assay methods.

Gateway towards recent developments in quantum dot-based light-emitting diodes.

Quantum dots (QDs), with their excellent photoluminescence, narrow emission linewidth, and wide color coverage, provide unrivaled advantages for advanced display technologies, enabling full-color micro-LED displays. It is indeed critical to have a fundamental understanding of how QD properties affect micro-LED display performance in order to develop the most energy-efficient display device in the near future. However, to take a more detailed look at the stability issues and passivation ways of QDs is essential for accelerating the commercialization of QD-based LED technologies. Knowing about the most recent breakthroughs in QD-based LEDs can give a good indication of how they might be used in shaping the future of displays. In this review, we discuss the characteristics of QD-based LEDs for the applications of display and lighting technologies. Various approaches for synthesis and the stability improvement of QDs are addressed in detail, along with recent advancements towards QD-based LED breakthroughs. Moreover, we summarize our latest research findings in QD-based LEDs, providing valuable information about the potential of QD-based LEDs for future display technologies.

A flexible capacitive photoreceptor for the biomimetic retina.

Neuromorphic vision sensors have been extremely beneficial in developing energy-efficient intelligent systems for robotics and privacy-preserving security applications. There is a dire need for devices to mimic the retina's photoreceptors that encode the light illumination into a sequence of spikes to develop such sensors. Herein, we develop a hybrid perovskite-based flexible photoreceptor whose capacitance changes proportionally to the light intensity mimicking the retina's rod cells, paving the way for developing an efficient artificial retina network. The proposed device constitutes a hybrid nanocomposite of perovskites (methyl-ammonium lead bromide) and the ferroelectric terpolymer (polyvinylidene fluoride trifluoroethylene-chlorofluoroethylene). A metal-insulator-metal type capacitor with the prepared composite exhibits the unique and photosensitive capacitive behavior at various light intensities in the visible light spectrum. The proposed photoreceptor mimics the spectral sensitivity curve of human photopic vision. The hybrid nanocomposite is stable in ambient air for 129 weeks, with no observable degradation of the composite due to the encapsulation of hybrid perovskites in the hydrophobic polymer. The functionality of the proposed photoreceptor to recognize handwritten digits (MNIST) dataset using an unsupervised trained spiking neural network with 72.05% recognition accuracy is demonstrated. This demonstration proves the potential of the proposed sensor for neuromorphic vision applications.

Titanium nanoparticle anchored functionalized MWCNTs for electrochemical detection of ractopamine in porcine samples with ultrahigh sensitivity.

We develop a disposable electrochemical sensor using a titanium nanoparticles (Ti NPs)-anchored functionalized multi-walled carbon nanotube (Ti@f-MWCNTs) composite as electrochemical sensing interface for the detection of ractopamine (RAC). The sensor demonstrated superior electrochemical sensing ability with a broad linear response range (0.01-185 µM) and ultralow detection limit (0.0038 µM). In addition, the stability, repeatability, reproducibility, and anti-interference ability of the Ti@f-MWCNTs sensor were satisfactory. The practicability of the sensor was effectively employed for the determination of RAC in porcine samples including pork, pig urine, and pig serum with substantial recoveries in the range of 92%-99% and a relative standard deviation of less than 5%.

Disposable and cost-effective label-free electrochemical immunosensor for prolactin based on bismuth sulfide nanorods with polypyrrole.

Prolactin (PRL) is produced by the pituitary gland and plays a vital role in the production of milk after a baby is born. PRL levels are normally elevated in pregnant and nursing women, and high levels of PRL in the human body cause hyperprolactinemia, infertility, galactorrhea, infrequent or irregular periods, amenorrhea, breast pain, and loss of libido. Accordingly, herein, a novel label-free immunosensor using a bismuth sulfide/polypyrrole (Bi2S3/PPy)-modified screen-printed electrode (SPE) for the fast and facile detection of the peptide hormone PRL. Bi2S3 nanorods were synthesized via a facile hydrothermal technique, and PPy was prepared by chemical polymerization method. Subsequently, the Bi2S3/PPy/ SPE was modified with 3-mercaptopropionic acid (MPA) and EDC/NHS. Owing to the cross-linking effect of EDC/NHS, antibody-PRL (anti-PRL) was firmly stabilized on the modified SPE surface. These layer-by-layer modifications enhanced the conducting properties, anti-PRL loading capacity, and sensitivity of the developed immunosensor. Under optimized conditions, the PRL immunosensor demonstrated a broad linear range of approximately 1-250 ng/mL, a low detection limit of approximately 0.130 ng/mL (3 × SD/b), good specificity, reproducibility, and stability. PRL was successfully evaluated in human and mouse serum samples, and the corresponding outcomes were compared with those of the electrochemical and ELISA methods.

Self-templating hydrothermal synthesis of carbon-confined double-shelled Ni/NiO hollow microspheres for diphenylamine detection in fruit samples.

Toxic substances, such as heavy metals, toxins, pesticides, pathogens, and veterinary drug residues in food are hazardous to consumer health. The variety and quantity of food consumption have increased owing to developments in the agricultural and food industries. Food safety has a substantial socioeconomic impact, and an increasing number of consumers have become aware of its importance. Therefore, simple and cost-effective analytical methods are required to quantify the safety of preservatives. Herein, we report an electrochemical method using double-shelled carbon-confined Ni/NiO (C@Ni/NiO) hollow microspheres to detect diphenylamine (DPA). The microspheres were synthesized by a self-templating hydrothermal method followed by calcination. The hydrothermal temperature and precursor ratio were optimized systematically to prepare double-shelled C@Ni/NiO hollow microspheres. The excellent electrocatalytic activity and electron transport properties of a C@Ni/NiO-modified glassy carbon electrode (GCE) were exploited in the electrochemical oxidation of DPA. Interestingly, the engineered C@Ni/NiO/GCE has a wide dynamic linear range (0.02-473 µM) and a DPA detection limit of 0.007 µM. In addition, the DPA sensor exhibited good selectivity, reproducibility, repeatability, and stability. The practical feasibility of the DPA sensor was evaluated in fruit samples (sweet tomatoes, apples, and red grapes), with considerable recovery.

Unraveling the origin of ferroelectric resistance switching through the interfacial engineering of layered ferroelectric-metal junctions.

Ferroelectric memristors have found extensive applications as a type of nonvolatile resistance switching memories in information storage, neuromorphic computing, and image recognition. Their resistance switching mechanisms are phenomenally postulated as the modulation of carrier transport by polarization control over Schottky barriers. However, for over a decade, obtaining direct, comprehensive experimental evidence has remained scarce. Here, we report an approach to experimentally demonstrate the origin of ferroelectric resistance switching using planar van der Waals ferroelectric α-In2Se3 memristors. Through rational interfacial engineering, their initial Schottky barrier heights and polarization screening charges at both terminals can be delicately manipulated. This enables us to find that ferroelectric resistance switching is determined by three independent variables: ferroelectric polarization, Schottky barrier variation, and initial barrier height, as opposed to the generally reported explanation. Inspired by these findings, we demonstrate volatile and nonvolatile ferroelectric memristors with large on/off ratios above 104. Our work can be extended to other planar long-channel and vertical ultrashort-channel ferroelectric memristors to reveal their ferroelectric resistance switching regimes and improve their performances.

Highly Selective Self-Powered Organic-Inorganic Hybrid Heterojunction of a Halide Perovskite and InGaZnO NO2 Sensor.

Self-powered sensors can lead to disruptive advances in self-sustainable sensing systems that are imperative for evolving human lifestyles. For the first time, we demonstrate the fabrication of a heterojunction sensor using p-type hybrid-halide perovskites (CH3NH3PbBr3) and an n-type semiconducting metal oxide thin film [InGaZnO (IGZO)] for the detection of NO2 gas and power generation. Combining the excellent photoelectric properties of perovskites and the remarkable gas-sensing properties of IGZO at room temperature, the devised sensors generate open-circuit voltage and modulate according to the ambient NO2 concentration. The major challenge in devising self-powered gas sensors is to attain harvesting capability and selectivity simultaneously, owing to perovskites reactivity in the presence of oxygen and humidity. In this work, we developed a novel approach and fabricated a heterojunction sensor using parylene-c as an additional layer to curb the cross-sensitivity and to enhance the selectivity of the sensor. Even under the low concentrations of NO2, the developed sensor exhibits remarkable sensitivity, selectivity, and repeatability. The devices are sensitive and robust even under extreme humidity conditions (80% RH) and synthetic air. The devised sensor configuration is one way to eliminate the cross-sensitivity issue of the perovskite-based devices and serves as a reference for the development of self-powered sensors.

Label-free electrochemical immunosensor based on gold nanoparticle/polyethyleneimine/reduced graphene oxide nanocomposites for the ultrasensitive detection of cancer biomarker matrix metalloproteinase-1.

Matrix metalloproteinase-1 (MMP-1) is associated with many types of cancers, including oral, colorectal, and brain cancers. This paper describes the fabrication of an MMP-1 immunosensor based on a gold nanoparticle/polyethyleneimine/reduced graphene oxide (AuNP/PEI/rGO)-modified disposable screen-printed electrode (SPE). A microwave-assisted single-step method was employed for the simultaneous reduction of gold and graphene oxide in a PEI environment to avoid AuNP agglomeration. The crystal structure, chemical composition, optical properties, and interior morphology of the materials were probed by X-ray diffraction, Raman spectroscopy, UV-visible spectrometry, and transmission electron microscopy techniques. To assemble a label-free MMP-1 immunosensor layer-by-layer, 3-mercaptopropionic acid was utilized due to its strong sulfur-gold bonding ability, and its tail end was attached to a carboxyl group, allowing the MMP-1 antibody (anti-MMP-1) to be subsequently cross-linked using the traditional N-(3-dimethylaminopropyl) and N' ethylcarbodiimide hydrochloride method. Differential pulse voltammetry analysis showed a linear relationship with MMP-1 concentration in the range of 1-50 ng ml-1 with an R2 value of ∼0.996 (n = 5, RSD < 5%). This immunosensor was successfully applied for MMP-1 detection in urine, saliva, bovine serum, and cell culture media (HSC-3 & C6) of oral and brain cancers showing results comparable to those of the credible ELISA method.

Halide Perovskites: A New Era of Solution-Processed Electronics.

Organic-inorganic mixed halide perovskites have emerged as an excellent class of materials with a unique combination of optoelectronic properties, suitable for a plethora of applications ranging from solar cells to light-emitting diodes and photoelectrochemical devices. Recent works have showcased hybrid perovskites for electronic applications through improvements in materials design, processing, and device stability. Herein, a comprehensive up-to-date review is presented on hybrid perovskite electronics with a focus on transistors and memories. These applications are supported by the fundamental material properties of hybrid perovskite semiconductors such as tunable bandgap, ambipolar charge transport, reasonable mobility, defect characteristics, and solution processability, which are highlighted first. Then, recent progresses on perovskite-based transistors are reviewed, covering aspects of fabrication process, patterning techniques, contact engineering, 2D versus 3D material selection, and device performance. Furthermore, applications of perovskites in nonvolatile memories and artificial synaptic devices are presented. The ambient instability of hybrid perovskites and the strategies to tackle this bottleneck are also discussed. Finally, an outlook and opportunities to develop perovskite-based electronics as a competitive and feasible technology are highlighted.