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This study presents investigations into the fabrication, characterization, and performance analysis of stretchable white random lasers based on 2D glutamine(GLN)‐functionalized WS2 quantum dots (QDs) enhanced by the integration of Au nanoparticles (NPs) and a wrinkled graphene structure. Wrinkled graphene holds the potential for achieving transient population inversion through electron collisions. Incorporating Au NPs introduces localized surface plasmon resonance (LSPR), which enhances the light‐matter interaction, resulting in reduced lasing thresholds. The GLN‐functionalized WS2 QDs exhibit strong photoluminescence emission, and their integration with a wrinkled graphene structure and Au NPs creates a synergistic effect that enhances the emission efficiency and enables the realization of white random lasing. The extensive characterization and analysis of the emission spectra under different deformation ratios provide valuable insights into the tunability and reliability of these devices, as well as the importance of light trapping due to the wrinkled graphene structure. The findings of this study underscore the significant potential of LSPR and wrinkled graphene structure induced stretchable and white random lasers based on 2D GLN‐functionalized WS2 QDs. These lasers may have a promising application in the field of flexible and wearable photonics, which is a critical step towards the development of next‐generation optoelectronic devices with improved performance. [ABSTRACT FROM AUTHOR]

In this era of exponential progress in the internet of things (IoT) and artificial intelligence (AI), there is a pressing demand for devices that offer greater storage density, faster transmission rate, and enhanced data security within the realm of information technology. To achieve these advantages, a novel magnetoelectric light-emitting memory (LEM) device that can control the output light intensity and electrical signal based on the input magnetic and electric field strengths has been proposed and demonstrated. An ITO/P3HT–COOH/CdSe–ZnS QDs/ZnO/Ag quantum dot light-emitting diode (QLED), an Ag/PMMA/Au resistive random access memory (RRAM), and a PDMS : FeNi/AgNWs/air gap/Au magnetoelectric device with a micro-pyramid structure are integrated in tandem. This novel integrated device can receive magnetic and electrical input signals and transform them into electrical and optical output signals. In addition, it possesses several intriguing characteristics, such as a low operation current, a high ON/OFF ratio, multiple levels, and a controllable light intensity with magnetic stimuli to achieve a paralleled reading process. Furthermore, the magnetoelectric LEM device can emit specific patterns of light. It is possible to read the encoded data when the desired magnitude of a magnetic field, electric voltage, and the correct light pattern are satisfied. Therefore, this brand-new and creative device is very useful and timely for application in many fields, such as data communication and encryption technology. [ABSTRACT FROM AUTHOR]

Nonvolatile memory is an indispensable component of electronic devices. However, the current technology makes it difficult to satisfy the emerging big data demand. To circumvent the existing problems, herein, a first attempt is made to achieve multifunctional nonvolatile memory based on all 2D heterostructures, consisting of histidine‐doped molybdenum disulfide quantum disks mixed with graphene oxide and a graphene macroscopic heterojunction. The designed device possesses intriguing hybrid electrically and optically controllable nonvolatile memory functionalities. By harnessing the unique properties of these materials, memory devices demonstrate long‐term stability and nonvolatile characteristics under both optical and electrical control signals. These devices possess outstanding features, such as multiple read‐write cycles, multi levels, and fast switching speeds, overcoming the limitations of traditional components. To explore the underlying physical mechanism, the Fermi level of graphene is measured and it is confirmed that the charge transfer and trapping across the heterojunctions are the major factors responsible for the observed behavior. This study demonstrates that 2D heterostructures for hybrid optically and electrically controllable nonvolatile memory pave an alternative route for the next‐generation information technology. [ABSTRACT FROM AUTHOR]

Designing a photoredox material with highly efficient organic pollutant degradation ability and cost effectiveness is challenging. Conventional photoredox materials have inherent drawbacks, including high cost, low photon‐to‐electron conversion rates, and low effective surface area. Herein, an alternative nanoporous semiconductor/metal hybrid (CuO‐Ag) photoredox catalysis material with all solution processes is developed to circumvent these shortcomings. The obtained results evidently indicate that the loading of Ag onto the CuO nanoporous material leads to improving the Brunauer–Emmett–Teller (BET) specific surface area (48.369 m2 g−1) with pore size (36.436 nm) and pore's volume (0.301 cm3 g−1) of CuO‐Ag nanoporsity. The improved semiconductor/metal hybrid surface area and porosity significantly enhance the photocatalytic efficiency (i.e., ≈99% degradation of RhB and 4‐NP), owing to the synergy effect. Additionally, the decoration of metal nanostructure enables to enhance photo‐absorption and the semiconductor/metal heterojunction is useful to enhance photo‐excited electron and hole charge carriers separation. Such structure‐designed CuO‐Ag nanoporous materials maintain high photostability during long light irradiation conditions. The photocatalytic efficiency is better than all published reports. This strategy using hybrid semiconductor/metal nanoporous material with high surface area and greater porosity improved activity significantly offers a facile guideline for targeting photoredox catalysis applications. [ABSTRACT FROM AUTHOR]

Spin optoelectronics is an indispensable key for the future development of spintronics. In conventional spin light emitting diodes (LEDs), spin‐polarized carrier pairs are injected electrically into the light emitting layer and create circularly polarized light (CPL). Generally, spin‐polarized carriers are accomplished using ferromagnetic contacts or applying an external magnetic field, which will produce several drawbacks, including low temperature operation, low spin‐polarized carriers injection efficiency, etc. To circumvent the existing shortcomings, here, an alternative approach is proposed and achieves spin‐polarized LEDs at room temperature based on quantum dots (QDs)/chiral metal‐organic framework heterojunction without using ferromagnetic contacts or magnetic fields. The spin‐polarized injected layer composed of self‐assembled monolayer (SAM)/Chiral‐MOF ([Sr(9,10‐adc)(DMAc)2]n)) film, which produces spin‐polarized holes with spin orientation, determining the polarization and strength of circularly polarized electroluminescence (CP‐EL). The spin‐QLED emits CP‐EL at a rate of 12.24% efficiency, which provides an excellent alternative to generate new functionality for conventional QLEDs. The approach is anticipated to be very useful, enabling to offer a general methodology for generating not yet realized spin optoelectronic devices. [ABSTRACT FROM AUTHOR]

A biologically inspired anthocyanin-graphene hybrid heterojunction has been designed and demonstrated to serve as a highly pH-value sensitive and self-powered photodetector. The photosensor shows a photoresponsivity as high as 0.17 mA W−1 at 0 V and it can reach a pH value sensitivity of up to 0.2 pH unit. The charge transfer and the built-in electric field at the heterojunction can account for the observed photoresponse. The active source material, anthocyanin, is obtained from nature, and it can be dissolved in water without causing pollution. Together with its self-powered capability, the pH-value sensitive photodetector represents an excellent eco-friendly device. In view of the current issues of energy shortage and environment pollution, our study shown here could be very useful and practical for next-generation technology developments. [ABSTRACT FROM AUTHOR]

Indium selenide (InSe) is an emerging van der Waals material, which exhibits the potential to serve in excellent electronic and optoelectronic devices. One of the advantages of layered materials is their application to flexible devices. How strain alters the electronic and optical properties is, thus, an important issue. In this work, we experimentally measured the strain dependence on the angle-resolved second harmonic generation (SHG) pattern of a few layers of InSe. We used the exfoliation method to fabricate InSe flakes and measured the SHG images of the flakes with different azimuthal angles. We found the SHG intensity of InSe decreased, while the compressive strain increased. Through first–principles electronic structure calculations, we investigated the strain dependence on SHG susceptibilities and the corresponding angle-resolved SHG pattern. The experimental data could be fitted well by the calculated results using only a fitting parameter. The demonstrated method based on first–principles in this work can be used to quantitatively model the strain-induced angle-resolved SHG patterns in 2D materials. Our obtained results are very useful for the exploration of the physical properties of flexible devices based on 2D materials. [ABSTRACT FROM AUTHOR]

Hyperbolic metamaterial (HMM) has attracted considerable attention due to its enhanced light-matter interaction for tuning the photonic density of states and producing bulk plasmon polariton (BPP). In this study, we demonstrate the application of HMM in organic solar cells (OSCs) with superior performance for the first time. The designed HMM structure composed of multiple pairs of MoO3/Au stacks possesses a hyperbolic dispersion behavior in the primary light absorption regime of the photoactive material. To effectively couple BPP into the photoactive layer, the first pair of the HMM structure is designed to be a portion of the OSC structure, serving as the hole transport layer and anode. The unconventional HMM incorporated OSCs (HMM-OSCs) exhibit ∼29.4% enhancement in the power conversion efficiency (PCE) relative to similar OSCs using one pair of MoO3/Au and ∼11% improvement in PCE as compared to conventional OSCs with the fully reflective electrode. Compared to conventional OSCs, the performance improvement is primarily from the improved short circuit current density from a broad wavelength range of the enhanced photon-to-charge conversion efficiency due to the higher exciton generation and dissociation probability, as suggested by the photocurrent analysis and steady-state photoluminescence measurements. The experimental observation agrees well with that inferred from theoretical simulation for the enhancement in the local electric field and exciton generation rate for the designed HMM structure. Therefore, the designed HMM-OSCs can successfully couple BPP into operation with a large impact on light absorption efficiency enhancement. Our design principle can serve as a useful guideline for the application of HMM in other optoelectronic devices. [ABSTRACT FROM AUTHOR]

Stretchable devices, including various electronic and optoelectronic devices, are an emerging class of future wearable technology that have attracted great attention. In particular, owing to their excellent flexibility, 2D materials, such as graphene and transition metal dichalcogenide (TMDC), are suitable for providing high stability and durability in the fabrication of stretchable devices. However, in terms of 2D-based optoelectronic devices, photoresponsivity is low due to the weak absorption of their small layer thickness. To overcome this shortcoming, herein, a highly sensitive and stretchable hybrid 2D heterostructured and wrinkled photodetector based on MoS2 quantum disks and graphene is designed and demonstrated. Several factors are combined simultaneously to achieve stretchability and sensitivity, exceeding those designed with similar materials in most published reports. First, surface defects can be considerably reduced by doping suitable molecules on MoS2 quantum disks, and the doped MoS2 quantum disks show significantly enhanced absorption. Second, the photogenerated carriers in MoS2 quantum disks can easily transfer to the graphene layer, which serves as a highly conducting channel. Third, in addition to exhibiting the stretchable capability of over 100%, the wrinkled structure is useful to induce the light trapping effect, generate more electron–hole pairs, and enhance photosensitivity. Moreover, strong photocurrent enhancement can be obtained after incorporating gold nanoparticles into the graphene/TMDC-based wrinkled heterostructured photodetectors owing to the surface plasmon resonance effect. Our results presented here are therefore useful for developing future stretchable and wearable electronics with ultrahigh sensitivity. [ABSTRACT FROM AUTHOR]

Higher data transmission rates, broader bandwidths, better privacy, and security are indispensable for the current information‐explosive age. However, to achieve the desired functionalities still remains as a great challenge. In this study, a two‐terminal, vertical dual‐gate phototransistor, which can be controlled by light, electric and magnetic fields, is proposed, fabricated, and demonstrated. This phototransistor uses a tandem structure composed of an organic solar cell (OSC) of ITO/ZnO/P3HT:PC61BM/MoO3/Ag, a resistive random access memory (RRAM) of Ag/PMMA/Au and a magnetoelectric film with micropyramid structure of PDMS:FeNi/silver nanowires (AgNWs). This device integrates and couples the properties of each individual component enabling to respond to light, electric and magnetic fields and works as a dual‐gate transistor. Compared with conventional transistors, the proposed device carries several intriguing features, such as ultrafast photoresponse time of 3 µs, controllable photocurrent with a variety of external stimuli, high ON/OFF ratio greater than 103, and touchless human–machine interaction. All of the above features are beneficial for high‐speed optical communication and circuit miniaturization. Furthermore, its unique logical characteristics show great potential for information security in the future development of Li‐Fi optical communication. [ABSTRACT FROM AUTHOR]

The integration of 2D materials into future applications relies on advances in their quality and production. We here report a synthesis method that achieves ultrahigh optoelectronic performance at unprecedented fabrication scales. A mediator-assisted chemical vapor deposition process yields tungsten-disulfide (WS2) with near-unity photoluminescence quantum yield, superior photosensitivity and improved environmental stability. This enhancement is due to the decrease in the density of lattice defects and charge traps brought about by the self-regulating nature of the growth process. This robustness in the presence of precursor variability enables the high-throughput growth in atomically confined stacks and achieves uniform synthesis of single-layer WS2 on dozens of closely packed wafers. Our approach enhances the scientific and commercial potential of 2D materials as demonstrated in producing large-scale arrays of record-breaking optoelectronic devices. [ABSTRACT FROM AUTHOR]

Infrared-to-visible upconversion (IVU) possesses a variety of applications, spanning from bio-imaging to anti-counterfeiting, and has attracted great attention. However, the devices developed in previous studies suffer from several drawbacks, such as relatively weak optical absorption, requirement of a complicated design, and a costly fabrication process, which limit their potential practical application. To circumvent the existing difficulties, in this study, an IVU device based on infrared quantum dots (QDs) and a mixture of visible QD light-emitting diodes (QLEDs) with low operational voltage and multiple changeable visible colors is demonstrated. The emission color of this IVU-QLED can be easily manipulated under different input currents and power densities of incident infrared radiation. The IVU-QLED device can also be achieved with cost-effective and simple solution fabrication processes. In addition, this dual electrical-optical modulated IVU-QLED shows a fast response time. With the unexplored features of IVU, including infrared-visible upconversion, tunable visible color emission, dual functional modulation, and cost-effectiveness, the designed IVU-QLEDs shown here provide an alternative route for the development of untouched optoelectronic devices, which should be very useful and timely for future applications covering anti-counterfeiting, infrared sensing, bio-imaging, night vision, etc. [ABSTRACT FROM AUTHOR]