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In this concept, we showcase the upsurge in the studies of dynamic ultralong room‐temperature phosphorescence (RTP) materials containing inorganic and/or organic components as versatile photo‐responsive platforms. The goal is to provide a comprehensive analysis of photo‐controllable RTP, and meanwhile delve into the underlying RTP properties of various classes of photochromic materials including metal‐organic complexes, organic‐inorganic co‐crystals, purely organic small molecules and organic polymers. In particular, the design principles governing the integration of the photochromic and RTP moieties within a single material system, and the tuning of dynamic RTP in response to light are emphasized. As such, this concept sheds light on the challenges and opportunities of using these tunable RTP materials for potential applications in optoelectronics, particularly highlighting their use of reversible information encryption, erasable light printing and rewritable smart paper. [ABSTRACT FROM AUTHOR]

We combine biodegradable plastic (polyvinyl alcohol/glycerol polymer), and cellulose-based tissue paper in a very short time (5 s) by a facile way to form a new matrix, named plastic-paper, which has high optical transmittance (~ 89%) and high optical haze (~ 90%) in broadband. Results showed that the plastic-paper is durable in different solvents, with high folding strength (over 3500 folding times) and good mechanical strength (> 30 MPa tensile strength). Interestingly, the plastic-paper presents a two-sidedness of surface morphology. The smooth side shows high light transmittance and the rough side presents high optical haze. The smooth side of the plastic-paper is successfully applied to Organic Light-Emitting Diode (OLED). When the rough surface of plastic-paper is used in solar cells, the maximum output power increases by 2.6% compared with bare solar cells. The developed plastic-paper with high optical transmittance and high optical haze holds a great potential in flexible optoelectronic devices. [ABSTRACT FROM AUTHOR]

Chirality at the nanoscale has emerged as a key area of interest in materials science and engineering, with significant implications for various fields such as spintronics, photonics, optoelectronics, quantum computing, and biomedicine. With their unique properties such as enantioselective interactions with light and spin-polarized electron transport, chiral nanomaterials are opening a new window of opportunities for the design of advanced functional devices. This editorial provides an overview of the current state of research in chirality in nanomaterials. We also showcase several papers from this collection that exemplify the breadth of current work, offering insights into the future directions of this rapidly evolving field. [ABSTRACT FROM AUTHOR]

This work presents a study of piezoelectric zinc oxide (ZnO) thin films deposited by a novel post‐reactive sputtering method. The process utilizes a rotating drum with DC magnetron sputtering deposition onto substrates with subsequent DC plasma‐assisted oxidation of the deposited metal to metal oxide. The paper analyzes the influence of plasmaassisted magnetron sputtering (PA‐MS) deposition parameters (O2 plasma source power, O2 flow, and Ar flow) on the morphological, structural, optical, and piezoelectric properties of ZnO thin films. Design of experiments has been utilized to evaluate the role of these parameters on the growth rate (rg) and the properties of resulting films. Results indicate a predominant influence of the plasma power on the rg over other parameters. Among the eight tested samples, three of them show high crystal quality with high intensity (0001) diffraction peak, characteristic of the wurtzite crystalline structure of ZnO, and one of them exhibits piezoelectric coefficient values of ≈11pC N−1. That sample corresponding to a ZnO film deposited at the lowest rg of 0.075 nm s−1, confirmed the key role of the deposition parameters on the piezoelectric response of films, and demonstrated PA‐MS as a promising technique to produce high‐quality piezoelectric thin films. [ABSTRACT FROM AUTHOR]

Quantum dots (QDs) are becoming essential materials for future scientific and real-world applications, owing to their interesting and distinct optical and electrical properties compared to their bulk-state counterparts. The ability to tune the bandgap of QDs based on size and composition—a key characteristic—opens up new possibilities for enhancing the performance of various optoelectronic devices. These advances could extend to cutting-edge applications such as ultrawide-band or dual-band photodetectors (PDs), optoelectronic logic gates, neuromorphic devices, and security functions. This paper revisits the recent progress in QD-embedded optoelectronic applications, focusing on bandgap tunability. The current limitations and challenges in advancing and realizing QD-based optoelectronic devices are also discussed. [ABSTRACT FROM AUTHOR]

This paper presents an 8 × 8 channel optoelectronic readout array (ORA) realized in the TSMC 180 nm 1P6M RF CMOS process for the applications of short-range light detection and ranging (LiDAR) sensors. We propose several circuit techniques in this work, including an amplitude-to-voltage (A2V) converter that reduces the notorious walk errors by intensity compensation and a time-to-voltage (T2V) converter that acquires the linear slope of the output signals by exploiting a charging circuit, thus extending the input dynamic range significantly from 5 μApp to 1.1 mApp, i.e., 46.8 dB. These results correspond to the maximum detection range of 8.2 m via the action of the A2V converter and the minimum detection range of 56 cm with the aid of the proposed T2V converter. Optical measurements utilizing an 850 nm laser diode confirm that the proposed 8 × 8 ORA with 64 on-chip avalanche photodiodes (APDs) can successfully recover the narrow 5 ns light pulses even at the shortest distance of 56 cm. Hence, this work provides a potential CMOS solution for low-cost, low-power, short-range LiDAR sensors. [ABSTRACT FROM AUTHOR]

In this paper, the crystal structure, optical and electronic properties of two related rubidium iodide halide perovskites RbSiI3 and RbGeI3 are investigated and discussed thoroughly. The calculations of these properties are performed using the generalized gradient approximation under Perdew–Burke–Ernzerhof functional (GGA–PBE). Also, the structural optimizations and accurate optoelectronic properties have been achieved by exploiting full-potential linearized augmented plane wave method (FP-LAPW). Analysis of optimization results exposed that the volume per unit cell and lattice parameter (a0 = 5.8348 Å (RbSiI3)) and (a0 = 5.9631 Å (RbGeI3)) are closely in agreement with the previous results. In addition, the calculated values of tolerance factor (TF ≈ 1.0) satisfy the creation criterion for perovskites, and the negative and small values of formation energy (ΔFE) confirm the chemical stability of studied compounds. The results of density of states and band structures reveal that RbSiI3 and RbGeI3 are nonmagnetic semiconductors having a proper direct energy gap (Eg) of 0.465 and 0.953 eV, respectively, along the M–M symmetry directions in the first Brillouin zone. The 2-D distributions of charge density confirm that the chemical bonding of Rb–I and Si/Ge–I bonds obey the covalent and ionic nature. Moreover, we have calculated and discussed the optoelectronic properties, real ε1(ω) and imaginary ε2(ω) functions, optical absorption α(ω), reflectivity R(ω) and refractivity n(ω). The results obtained in this study like structural stability, suitable Eg and highly accurate optical absorption α(ω) of visible light waves, indicate the possible exploitation of semiconductors RbSiI3 and RbGeI3 and make them candidate materials for optoelectronics, such as photovoltaic solar cells, photosensors, photodetectors and photodiodes devices. [ABSTRACT FROM AUTHOR]

The traditional base station in C-RAN is divided into three parts: a pool of centralized baseband units (BBUs), a fronthaul network that links the BBUs and remote radio units (RRUs), and RRUs. This paper proposes a novel cooperative algorithm for resource optimization in a time-wavelength division multiplexed (TWDM) passive optical network (PON) incorporating a cloud radio access network (C-RAN). First, a joint collaborative strategy is deployed to optimize cooperative caching and transmission in the wireless and optical domains. Then, the quality of experience (QoE) is improved by bandwidth configuration and caching. Simulation results show that the average throughput of the proposed QoE-aware video cooperative caching and transmission mechanism (QACCTM) algorithm is approximately 30% higher than that of other algorithms. Compared with the relative average residual clutter power (RARCP) and quality-aware wireless edge caching (QAWEC) algorithms, the proposed QACCTM algorithm reduces the access delay by approximately 27.1% and 15.9%, respectively. [ABSTRACT FROM AUTHOR]

Despite the ever‐increasing demand for transparent power sources in wireless optoelectronics, most of them have still relied on synthetic chemicals, thus limiting their versatile applications. Here, a class of transparent nanocellulose paper microsupercapacitors (TNP‐MSCs) as a beyond‐synthetic‐material strategy is demonstrated. Onto semi‐interpenetrating polymer network‐structured, thiol‐modified transparent nanocellulose paper, a thin layer of silver nanowire and a conducting polymer (chosen as a pseudocapacitive electrode material) are consecutively introduced through microscale‐patterned masks (which are fabricated by electrohydrodynamic jet printing) to produce a transparent conductive electrode (TNP‐TCE) with planar interdigitated structure. This TNP‐TCE, in combination with solid‐state gel electrolytes, enables on‐demand (in‐series/in‐parallel) cell configurations in a single body of TNP‐MSC. Driven by this structural uniqueness and scalable microfabrication, the TNP‐MSC exhibits improvements in optical transparency (T = 85%), areal capacitance (0.24 mF cm−2), controllable voltage (7.2 V per cell), and mechanical flexibility (origami airplane), which exceed those of previously reported transparent MSCs based on synthetic chemicals. [ABSTRACT FROM AUTHOR]

Self-powered flexible photodetectors which can efficiently and sustainably operate without the need for external electric input are important in today's era for portable and optoelectronics devices. Paper-based photodetectors integrate advantages, like high flexibility, bio-degradability, large photosensitive area, and low fabrication cost. Herein, we have developed large area, broadband, and highly stable photodetectors based on Graphite/ZnO–WS2 nanohybrid on paper. Encouragingly, Graphite/ZnO–WS2 nanohybrids show self-powered photodetection with a high responsivity of 7.1 × 10–2 mA/W in the visible spectral range to 9.8 mA/W in NIR spectral range. Also, the photodetector exhibited excellent photoresponsivity of 1.80 A/W, detectivity of 1.5 × 1012 Jones, and EQE of 207% under the illumination at 1080 nm with a light intensity of 50 µW/cm2 at 0.2 V bias. Due to excellent binding between the paper and detector active materials as well as the high flexibility of the paper, the device shows greater flexibility and stability up to 1000 bending cycles. Moreover, the photodetector exhibits high stability in humid and ambient environments. [ABSTRACT FROM AUTHOR]

Phase-pure crystalline cubic boron nitride (c-BN) thin films are of immense scientific and technical interest because of their suitable properties for optoelectronic and high-power applications, high thermal conductivity and hardness, chemical inertness to ferrous materials in high-temperature and caustic environments, and high optical transmittance over a broad wavelength range from the ultraviolet (UV) to the visible spectrum. However, the lack of controlled fabrication techniques for high-quality c-BN films significantly affects the reliable practical applications of this material. Recently, phase-pure single-crystal c-BN and a new phase of BN with unique properties, called quenched-BN (Q-BN), have been synthesized using a pulsed laser annealing (PLA) technique to overcome the current impediments in c-BN synthesis. This review paper comprehensively examines the current status of analytical research on the growth, characterization, and properties (optical and electrical) of c-BN films fabricated by different synthesis techniques, with a particular emphasis on the immensely promising PLA technique. In particular, the paper focuses on the processes used to obtain phase-pure c-BN films via epitaxial growth, characterization of defects and interfaces, and control of the structural, electrical, and optical properties of these films by controlling the growth parameters, including the laser–solid interaction for the direct conversion of nanocrystalline hexagonal boron nitride (h-BN) into crystalline c-BN using the PLA technique. The latest developments in c-BN electronics are also discussed, with a focus on producing p-and n-type conductivity using different dopants to achieve dopant concentrations far beyond the retrograde thermodynamic solid solubility limits. Finally, the future prospects and possible applications in emerging areas are discussed, as well as the goals and guidelines for future research of PLA-grown c-BN films. A comprehensive overview of the properties, application, characterization, shortcomings, and future prospects of c-BN [ABSTRACT FROM AUTHOR]

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Solution-processed all-inorganic CsPbBr3 perovskite thin films show great promise for green lasers owing to their unique optoelectronic properties and processability. However, the amplified spontaneous emission (ASE) of CsPbBr3 films with poor heat dissipation still experiences instability due to severe heating effects under high optical pump densities. Here we demonstrate CsPbBr3:GO films with excellent photostability and ASE properties under ambient conditions by incorporating graphene oxide (GO) as an additive. As the amount of GO increases, the photostability of the perovskite film is improved and the ASE threshold is decreased, while the film surface remains smooth and compact. Moreover, a low threshold of ASE is sustained even after annealing the composite films at 130 °C for 24 hours. These results suggest that the synthesis of CsPbBr3:GO will open new avenues for controlling the optical properties of perovskite films and advancing the development of optoelectronic devices. [ABSTRACT FROM AUTHOR]

This paper presents a simple method to transform two‐dimensional data sets into a format that can be easily processed into sound files. These files can be loaded into software wavetable synthesizers to create audible forms of data that can represent complex information. Some background about sonification will be discussed, and the simple method developed here will be applied to graphene optoelectronics. Some key illustrative examples will be used to demonstrate the method, including data sets from previous work on light emission from graphene field effect transistors. We use the sonification method to show how changes in observed phenomena (e.g., light emission intensity and spectral shape) result in changes of the resulting sound (such as the timbre). Demonstrations are included in video format to hear and illustrate the method and resulting effects. [ABSTRACT FROM AUTHOR]

The ternary ZnIn2S4 has recently gained significant attention due to its potential applications in various optoelectronics and photocatalysis sectors. In the current study, ZnIn2S4 nanoparticles were prepared using a simple microwave-assisted synthesis method with different irradiation powers varying from 180 W--720 W. Structural analysis confirmed their polycrystalline nature with the appearance of ZnIn2S4 and In2S3 phases. The variation in diffraction pattern intensity and Raman vibrational bands with irradiation power indicates structural rearrangements induced with power variation. Morphological studies confirmed the formation of agglomerate nanoparticles with size variation as induced by different microwave powers. Broad absorption across the visible and near-infrared regions and the increased band gap enhance their photocatalytic and sensing applications. An increased irradiation power in the ZnIn2S4 lattice reduced intermediate levels within the band gap, altering the optical responsiveness. The blue shift in absorption edges with microwave power increased the optical band gap by reducing disorder and defects. The refractive indices were estimated using different theoretical models and reduced with an increase in the band gap. Thermal analysis revealed endothermic peaks. These ZnIn2S4 nanoparticles displayed an enhanced photocurrent under white light, increasing tenfold with microwave power. The greater powered ZIS (ZIS-720 W) nanomaterial showed the best photoresponse and is well suited for optoelectronic application. All of their optical and electrical properties make them suitable for various optoelectronic devices, particularly in detection applications. [ABSTRACT FROM AUTHOR]

Halide perovskite materials offer significant promise for solar energy and optoelectronics yet understanding and enhancing their efficiency and stability require addressing lateral inhomogeneity challenges. While photoluminescence imaging techniques are employed for the measurement of their opto‐electronic and transport properties, going further in terms of precision requires longer acquisition times. Prolonged exposure of perovskites to light, given their high reactivity, can substantially alter these layers, rendering the acquired data less meaningful for analysis. In this paper, a method to extract high‐quality lifetime images from rapidly acquired, noisy time‐resolved photoluminescence images is proposed. This method leverages concepts of the field of constrained reconstruction and includes the Huber loss function and a specific form of total variation regularization. Through both simulations and experiments, it is demonstrated that the approach outperforms conventional pointwise methods. Optimal acceleration and optimization parameters tailored for decay time imaging of perovskite materials, offering new perspectives for accelerated experiments crucial in degradation process characterization are identified. Importantly, this methodology holds the potential for broader applications: it can be extended to explore additional beam‐sensitive materials, and other imaging characterization techniques and employed with more complex physical models to treat time‐resolved decays. [ABSTRACT FROM AUTHOR]

With the continuous development of flexible electronics, multi-functional device integration, artificial intelligence technology, etc., flexible wearable sensors are playing an increasingly important role in people's daily motion monitoring. However, current flexible wearable sensors have problems such as low accuracy, poor real-time performance, and poor stability in motion monitoring, which seriously hinder the better application of flexible wearable sensors and are not conducive to the collection and monitoring of motion signals. To this end, this paper designed a flexible wearable sensor motion monitoring system and tested its performance through the preparation and performance research of new functional polymer conjugated materials. The research results show that the motion monitoring system designed based on the new functional polymer conjugated material flexible wearable sensor has good monitoring accuracy and real-time performance. When the output data is 500 pieces, the running monitoring accuracy reaches 95.4%, and the monitoring feedback time is 0.321 s; the high jump movement monitoring accuracy rate reaches 97%, and the monitoring feedback time is 0.287 s; the long jump movement monitoring accuracy rate reaches 96%, and the monitoring feedback time is 0.296 s. This shows that the flexible wearable sensor motion monitoring system of this paper has better performance and can meet the current demand for accuracy and realtime motion monitoring. This study highlights the impact of new functional polymer conjugated materials on flexible wearable sensors, helping to further solve the deficiencies of flexible wearable sensors in sports monitoring and promote their better development. [ABSTRACT FROM AUTHOR]

Flexible photodetectors functionalized by transition metal dichalcogenides have attracted great attention due to their excellent photo-harvesting efficiency. However, the field of optoelectronics still requires advancement in the production of large-area, broad band and flexible photodetectors. Here we report a flexible, stable, broad band and fast photodetector based on a MoS2/WSe2 heterostructure on ordinary photocopy paper with pencil-drawn graphite electrodes. Ultrathin MoS2/WSe2 nanohybrids have been synthesized by an ultrahigh yield liquid-phase exfoliation technique. The thin sheets of WSe2, and MoS2 contain two to four layers with a highly c-oriented crystalline structure. Subsequently, the photodetector was exploited under ultra-broad spectral range from 400 to 780 nm. The photodetector exhibits excellent figure of merit such as on/off ratio of the order of 103, photoresponsivity of 124 mA W−1 and external quantum efficiency of 23.1%. Encouragingly, rise/decay time of about 0.1/0.3 s was realized, which is better than in previous reports on paper-based devices. [ABSTRACT FROM AUTHOR]

In this paper, optical and transport properties of Polyvinyl Alcohol/Silver incorporated Zinc Oxide (PVA/Ag–ZnO) nanocomposites of varying Ag–ZnO nanoparticles content prepared by solution casting method are studied to explore their multifunctional applications. The nanocomposites are characterized using X-ray diffraction, Scanning electron microscope, Energy-dispersive X-ray analysis, UV–Visible spectroscopy and Fourier transform infra-red spectroscopy. The UV–visible spectra showed zero transmittance in the UV region with increasing Ag–ZnO nanoparticles content in the PVA matrix suggesting that the nanocomposites could be used as a potential UV shielding material. The optical band gap energy decreases from 5.77 to 1.54 eV with increasing Ag–ZnO nanoparticles content in the PVA matrix. Frequency- and temperature-dependent dielectric measurement of the samples reveals maximum dielectric constant at PVA/15 wt% Ag–ZnO nanocomposite. Dielectric loss results showed a lossless behaviour at higher frequencies (< 0.2), suggesting that the prepared samples are suitable for use in high-frequency applications. The AC conductivity studies reveal that electrical conduction mechanism in the nanocomposites is governed by the correlated barrier hopping mechanism. Activation energy calculation indicates the involvement of two different types of conduction mechanism in the samples. The Nyquist plot for all the samples is fitted using the equivalent circuit model. The studied results show that the PVA/Ag–ZnO nanocomposites can serve as potential candidates for optoelectronic and electronic device application. [ABSTRACT FROM AUTHOR]

High-performance photodetection is becoming increasingly important for the advancement of technology. Very few materials are available that can respond to light across the ultraviolet to the infrared (IR) range. These materials are very much required for optoelectronic devices. Two-dimensional (2D) layered materials became relevant following the discovery of graphene. Transition-metal chalcogenides belong to the 2D layered material class, as well. The field of optoelectronic applications makes extensive use of them. The current study investigated the photodetector device by doping pure SnS nanoflakes with Fe, Mn, Mg, Pd, and W. These materials were used to create paper-based, flexible, biodegradable electronics through a solvent-free hand-print technique. The Mg-doped SnS photodetector has the highest photo response performance among the devices. With a specific detectivity value of 1.64 × 1010 Jones and a responsivity value of 52 mA W–1, the 7% Mg-doped SnS exhibits the best response among the different Mg doping. Extensive on–off cycles were used to assess the switching stability of the device, observing clear photo response and photoswitching behavior. The photoswitching curves of the device as created and the device after 8 months show an amazing degree of consistency, indicating the device's resilience in open-air environments. The device was bent repeatedly to test its twisting, foldability, and flexibility. It continuously displayed a definite photoswitching trend. Testing in a very basic and acidic environment verified the device's chemical stability, and its photo response and photoswitching functions remain functional. When the paper-based photodetector's thermal stability was examined at various temperatures, the findings demonstrated that the device continues to function normally and produce photocurrent. Considering how quickly technology is developing nowadays and how much waste is produced by electronics, switching to paper-based gadgets could help achieve sustainability goals. [ABSTRACT FROM AUTHOR]

A novel crystal benzophenone's nonlinear optical applications are pivotal. Benzophenone is one of the promising organic nonlinear optics materials for their high energy laser photonic application. It has already been possible to generate crystals of benzophenone in various ways. In this research, the slow evaporation method at room temperature was successful in making a single crystal of benzophenone. In this paper, synthesis, growth, characterization and applications of low melting organic nonlinear optics benzophenone crystal in order to improve their structural and physical properties are reported. Different characterization methods were applied to the grown crystals. The lattice parameters of the grown material were obtained by single crystal X-ray diffraction (XRD) study. The results of the single crystal XRD analysis showed that the produced crystals are a component of an orthorhombic system with the space group P212121 and the lattice parameters are a = 7. 9 9 9 5 (9)  Å, b = 1 0. 2 8 6 5 (1 0)  Å, c = 1 2. 1 2 4 7 (1 3)  Å, α = β = γ = 9 0 ∘ and V = 9 9 7. 7 0 (1 8)  Å3. Ultraviolet-visible (UV–Vis) spectrum indicates that the crystal is transparent (72%) in the entire visible region with a cutoff wavelength of 258 nm. The transparency of the grown crystals has been confirmed using the UV–Vis spectrum. The second harmonic generation (SHG) efficiency of the grown crystal was measured using an Nd-YAG laser and it was found to be 1.8 greater than potassium dihydrogen orthophosphate (KDP). The FT-IR spectrum was examined in order to identify the many functional groups. The formation of the material was confirmed qualitatively by FT Raman spectral analyses. Mechanical properties such as Vicker's microhardness number, Yield strength, Fracture toughness, Brittleness index and Elastic stiffness constant values were determined using Vicker's microhardness test. The thermal stability of the grown crystal was studied by thermal analysis. [ABSTRACT FROM AUTHOR]

The paper provides a detailed treatment of the expected range performance for the laser rangefinder (LRF) developed for the Polish ImAging SaTellites (PIAST) space mission, where the distance between satellites within a constellation has to be measured during orbital flight. The satellites are equipped with corner cube retroreflectors (CCR) to increase the efficiency of laser back-reflection. A theoretical signal-to-noise range-dependence model was developed to determine the maximum expected range of the measurements. This model included the tilt-angle-dependent properties of the CCR far-field diffraction patterns (FFDP) which were measured experimentally. In addition, the specific parameters of the receiving optoelectronic circuit used were considered. The obtained results show that in the case of the constructed PIAST LRF (peak laser pulse power of 100 W, laser beam divergence of 5 mrad, receiving optical aperture diameter of 2 in, CCR diameter of 2 in), depending on the CCR angular inclination, a maximum measurement distance of 15-40 km is expected. [ABSTRACT FROM AUTHOR]

A series of novel discotic liquid-crystalline donor–acceptor (D–A) dyads 5D10An (n = 4, 5, 6, 7, 8) adjusted by changing the chain length (n) of diester groups on perylene were synthesized based on triphenylene and perylene units, which were linked by a flexible linkage of 10-decyloxy-1-amine. Results from differential scanning calorimetry (DSC), one-dimensional X-ray diffraction (XRD) patterns, and polarized optical microscopy (POM) images indicate that 5D10A4, 5D10A5, 5D10A6, and 5D10A7 exhibited hexagonal columnar phase at high temperature ranges and rectangular columnar phases at room temperature. Combining the XRD data and the steady state spectra of UV-Vis and fluorescence spectroscopy, the intramolecular triphenylenes and perylene diester cores were stacked separately in distinct columns and nano-segregation occurred during self-assembly. The HOMO/LUMO energy levels were obtained using CV, UV-Vis spectroscopy, UPS and Gaussian09. Charge carrier mobilities were measured by a time-of-flight (TOF) device. These discotic liquid-crystalline compounds exhibited highly efficient ambipolar charge-transport properties, and the hole and electron mobilities can reach the order of 10−3 cm2 V−1 s−1 by segregated D–A columns. This is the first report on D–A dyads' discotic liquid crystals, which not only feature ambipolar transport but also exhibit columnar phase structures that can be stabilized at room temperature, providing potential utility of the strategy in organic optoelectronic applications. [ABSTRACT FROM AUTHOR]

Transparent paper with high transmission haze has garnered great attention due to its potential applications in light management of optoelectronics as a bulk optical material. Herein, we investigated the transmission haze and mechanical properties of transparent paper with different fiber species. The morphological dimensions of cellulose fibers (Northwood, Eucalyptus wood, Manila hemp) before and after 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) treatment were investigated in detail. The effect of fiber morphology and preparation methods on transmission haze and mechanical properties (tensile strength, Young’s modulus, bursting strength) of the resultant paper was then analyzed. The results showed that transparent paper with TEMPO-treated northern fibers possessed highest optical transmittance and transmission haze, as well as strongest mechanical strength compared to two other transparent paper. Furthermore, transparent paper prepared by solution casting exhibited higher mechanical strength, but lower transmission haze compared to paper prepared by vacuum filtration. It’s worth noting that sub-micro and nanofiber partially contributed to the transparency and mechanical properties of the resulting transparent paper. This work sheds light on the preparation of highly transparent and strong paper with excellent light scattering behavior for manipulating light behavior of optoelectronics as a bulk optical material. [ABSTRACT FROM AUTHOR]

In recent years, with the further ministration of the semiconductor device in integrated circuits, power consumption and data transmission bandwidth have become insurmountable obstacles. As an integrated technology, photonic integrated circuits (PICs) have a promising potential in the post‐Moore era with more advantages in data processing, communication, and diversified sensing applications for their ultra‐high process speed and low power consumption. Silicon photonics is believed to be an encouraging solution to realize PICs because of the mature CMOS process. The past decades have witnessed a huge growth in silicon PICs. However, there is still a demand for the development of silicon PICs to enable powerful chip‐scale systems and new functionalities. In this paper, a review of the photonic components, functional blocks, and emerging applications for PICs is offered. The common photonic components are classified into several sections, including on‐chip light sources, fiber‐to‐chip couplers, photonic resonators, waveguide‐based sensors, on‐chip photodetectors, and modulators. The functional blocks of the PICs mentioned in this review are photonic memories and photonic neural networks. Finally, the paper concludes with emerging applications for further study. [ABSTRACT FROM AUTHOR]

Excitonic devices are an emerging class of technology that utilizes excitons as carriers for encoding, transmitting, and storing information. Van der Waals heterostructures based on transition metal dichalcogenides often exhibit a type II band alignment, which facilitates the generation of interlayer excitons. As a bonded pair of electrons and holes in the separation layer, interlayer excitons offer the chance to investigate exciton transport due to their intrinsic out-of-plane dipole moment and extended exciton lifetime. Furthermore, interlayer excitons can potentially analyze other encoding strategies for information processing beyond the conventional utilization of spin and charge. The review provided valuable insights and recommendations for researchers studying interlayer excitonic devices within van der Waals heterostructures based on transition metal dichalcogenides. Firstly, we provide an overview of the essential attributes of transition metal dichalcogenide materials, focusing on their fundamental properties, excitonic effects, and the distinctive features exhibited by interlayer excitons in van der Waals heterostructures. Subsequently, this discourse emphasizes the recent advancements in interlayer excitonic devices founded on van der Waals heterostructures, with specific attention is given to the utilization of valley electronics for information processing, employing the valley index. In conclusion, this paper examines the potential and current challenges associated with excitonic devices. [ABSTRACT FROM AUTHOR]

A dual-sided metasurface structure, consisting of two different sets of sub-wavelength periodic metallic patterns on its two sides, can offer a promising platform for the design of multifunctional and directional insensitive devices. This paper presents an elaborative study of the structural and mathematical analyses of the frequency response of a dual-sided metasurface structure. It has been found that the ratio between resonating wavelength and the structure's thickness plays a deterministic role in achieving multi-functionality in such designs. The paper further presents an equivalent circuit model of the dual-sided metasurface structure to mathematically analyze the role of impedance in achieving directional insensitivity in such devices. The proposed structural and mathematical analysis has been validated together by designing a directional insensitive rasorber in the latter half of the paper. The analyses done in this paper can open up a broad avenue for the research and development of metasurface-based directional insensitive multifunctional optoelectronics devices. [ABSTRACT FROM AUTHOR]

The use of wearable sensors for calculating gait parameters has become increasingly popular as an alternative to optoelectronic systems, currently recognized as the gold standard. The objective of the study was to evaluate the agreement between the wearable Opal system and the optoelectronic BTS SMART DX system for assessing spatiotemporal gait parameters. Fifteen subjects with progressive supranuclear palsy walked at their self-selected speed on a straight path, and six spatiotemporal parameters were compared between the two measurement systems. The agreement was carried out through paired data test, Passing Bablok regression, and Bland-Altman Analysis. The results showed a perfect agreement for speed, a very close agreement for cadence and cycle duration, while, in the other cases, Opal system either under- or over-estimated the measurement of the BTS system. Some suggestions about these misalignments are proposed in the paper, considering that Opal system is widely used in the clinical context. [ABSTRACT FROM AUTHOR]

With the capacities of self-learning, acquainted capacities, high-speed looking for ideal arrangements, solid nonlinear fitting, and mapping self-assertively complex nonlinear relations, neural systems have made incredible advances and accomplished broad application over the final half-century. As one of the foremost conspicuous methods for fake insights, neural systems are growing toward high computational speed andmoo control utilization. Due to the inborn impediments of electronic gadgets, it may be troublesome for electronic-implemented neural systems to make the strides these two exhibitions encourage. Optical neural systems can combine optoelectronic procedures and neural organizationmodels to provide ways to break the bottleneck. This paper outlines optical neural networks of feedforward repetitive and spiking models to give a clearer picture of history, wildernesses, and future optical neural systems. The framework demonstrates neural systems in optic communication with the serial and parallel setup. The graphene-based laser structure for fiber optic communication is discussed. The comparison of different balance plans for photonic neural systems is made within the setting of hereditary calculation and molecule swarm optimization. In expansion, the execution comparison of routine photonic neural, time-domain with and without extending commotion is additionally expounded. The challenges and future patterns of optical neural systems on the growing scale and applications of in situ preparing nonlinear computing will hence be uncovered. [ABSTRACT FROM AUTHOR]

Abstract: Paper, one of the oldest materials for storage and exchange of human's information, has been reinvented as a building component of electronic and optoelectronic devices over the past decades with successful demonstration of paper‐based or paper‐using devices. These recent achievements can meet the demand for lightweight, cost‐effective, and/or flexible electronic and optoelectronic devices with advanced functionality and reduced manufacturing costs. This article provides a review of electronic and optoelectronic devices relying on or making use of the unique properties achievable with paper‐based materials. Basic scientific/technical principles, quantitative comparisons of material, electronic and/or optical properties, and benefits for each paper‐based application are given. Application‐specific research challenges, future design considerations, and development directions are also discussed. [ABSTRACT FROM AUTHOR]

Experimentally achieving the first‐ever electric field periodic poling of single crystal barium titanate oxide (BTO, or BaTiO3) thin film on‐insulator is reported. Owing to the outstanding optical nonlinearities of BTO, this result is a key step toward achieving quasi‐phase‐matching (QPM). First, the BTO thin film is grown on a dysprosium scandate substrate using pulsed laser deposition with a thin layer of strontium ruthenate later serving as the bottom electrode for poling. The characterization of the BTO thin film using x‐ray diffraction (XRD) and piezo‐response force microscopy to demonstrate single crystal, single domain growth of the film that enables the desired periodic poling, are presented. To investigate the poling quality, both non‐destructive piezo force response microscopy and destructive etching‐assisted scanning electron microscopy (SEM) are applied, and it is shown that high quality, uniform, and intransient poling with 50% duty cycle and periods ranging from 2 µm to 10 µm is achieved. The successful realization of periodic poling in BTO thin film unlocks the potential for highly efficient nonlinear processes under QPM that seemed far‐fetched with prior polycrystalline BTO thin films which predominantly relied on efficiency‐limited random or non‐phase matching conditions and is a key step toward integration of BTO photonic devices. [ABSTRACT FROM AUTHOR]

Halide perovskites have attracted increasingly attention as "rising star" materials for advanced photonics and optoelectronics. Construction micro‐/nano‐architecture of perovskites will provide a good platform to investigate and optimize the fundamental photon–matter–structure interaction. It will also improve the properties, pixelate and miniaturize the integration of versatile optoelectronic devices for emerging applications. In this regard, femtosecond (fs) laser processing technique has been widely used to fabricate micro‐/nano‐architecture with high spatial resolution, limitless flexibility, and unrestricted three‐dimensional structuring capability at a large‐scale, low‐cost way. Concurrently, it is reported that the high refractive index, low thermal conductivity and ultrafast thermalization rate of perovskites are beneficial for the processing by fs laser into micro‐/nano‐architecture without the degradation of their optoelectronic properties. This review systematically summarizes the interaction of fs laser with perovskites, including the mechanisms, and phenomena. Besides the traditional optoelectronics and applications of halide perovskites, the novel properties and applications from optical structures generated by fs laser processing of perovskites are also discussed. The challenges and outlooks for fs laser processed perovskite materials and devices are highlighted. This review will promote the relevant fundamental research on light–matter–structure interaction, and facilitate the integration of perovskite micro‐/nano‐architecture‐based optoelectronic devices. [ABSTRACT FROM AUTHOR]

Temperature dependency of band gap in CuO nano thin films has been investigated by virtue of transmission experiments at different temperatures. Structural and morphological characterization were achieved using X-ray diffraction (XRD) and scanning electron microscopy (SEM) measurements. Analysis on the XRD diffractogram revealed the presence of monoclinic structure for the CuO. Average crystallite size was determined as 17.8 nm. Absorption characteristics in between 10 and 300 K were presented in the wavelength range of 360–1100 nm. The band gap of the CuO was found to be ~ 2.17 eV at 300 K using Tauc and spectral derivative methods. This value increased to ~ 2.24 eV at 10 K. Both methods showed that the band gap extended with decreasing temperature. Temperature dependency of the band gap was studied using Varshni relation. The band gap at absolute temperature, variation of the band gap with temperature and Debye temperature were calculated as 2.242 ± 0.002 eV, − 5.4 ± 0.2 × 10−4 eV/K and 394 ± 95 K, respectively. [ABSTRACT FROM AUTHOR]

Two-dimensional semiconductors have shown great potential for the development of advanced intelligent optoelectronic systems. Among them, two-dimensional perovskite oxides with compelling optoelectronic performance have been thriving in high-performance photodetection. However, harsh synthesis and defect chemistry severely limit their overall performance and further large-scale heterogeneous integration. Here, we report the wafer-scale integration of highly oriented nanosheets by introducing a charge-assisted oriented assembly film-formation process and confirm its universality and scalability. The shallow-trap dominance induced by structural optimization endows the device with a distinguished performance balance, including high photosensitivity close to that of single nanosheet units and fast response speed. An integrated ultra-flexible 256-pixel device demonstrates the versatility of material-to-substrate integration and conformal imaging functionality. Moreover, the device achieves efficient recognition of multidirectional motion trajectories with an accuracy of over 99.8%. Our work provides prescient insights into the large-area fabrication and utilization of 2D perovskite oxides in advanced optoelectronics. Deng et al. report a charge-assisted oriented assembly for wafer-scale film formation of 2D perovskite oxide nanosheets. An ultra-flexible 256-pixel photodetector array enables conformal imaging capability and achieves high-accuracy motion recognition with the convolutional neural network. [ABSTRACT FROM AUTHOR]

P-type dye-sensitized solar cells have been fabricated with the sensitizer derived from tender coconut husk and Rhodamine B incorporated with and without co-doped (Co and Ce) nickel oxide (NiO) nanoparticles. NiO nanoparticles are obtained via green synthesis using the mesocarp of tender coconut. Graphene-coated FTO and I−/I3− have been used as counter cathode and electrolyte, respectively, in the cells. The cubic structure was confirmed from XRD spectra, and Debye–Scherrer and Williamson-Hall equations were used for the evaluation of crystalline size (13.3 and 8.5 nm) and parameters of dislocation density, etc. Fingerprints of the samples by molecular vibrations were found using FTIR and UV–visible spectroscopy. SEM imaging has been recorded for both the NiO nanoparticles. The fabricated solar cells were subjected to JV characterization studies. Co-doped (Co and Ce) solar cell has shown better efficiency of 0.259% with short circuit current density and open circuit voltage of 1.382 mA/cm2 and 0.387 V, respectively. [ABSTRACT FROM AUTHOR]

Residual fragments can remain after kidney stone extraction which may necessitate another intervention. A new approach needs to be developedis needed to lower the risk of disease severe side effects caused by these fragments. Magnetic nanoparticles can be applied due to their properties of being able to bind to residual fragments and to be extracted by an external magnetic field. Fractals and magnetic nanoparticles have been synthesized and characterized thoroughly. The small nanoparticles bind covalently to the kidney stones and a magnetic extraction of calcium oxalate fractals with magnetic nanoparticles is possible. The aggregation of nanoscale iron oxide nanoparticles can be induced with the addition of salt which improves the extraction process. The separation is validated by simulation and experimentally in a porcine kidney as well as in artificial kidney models. This proof-of-concept study successfullyis the fundament for a new waydemonstrated of extracting kidney stones extraction and including their fractals and might pave the way for new procedures in urology. [ABSTRACT FROM AUTHOR]

One of the major challenges in QLED research is improving the stability of the devices. In this study, we fabricated all inorganic quantum-dot light emitting diodes (QLEDs) using hafnium oxide (HfOx) as the hole transport layer (HTL), a material commonly used for insulator. Oxygen vacancies in HfOx create defect states below the Fermi level, providing a pathway for hole injection. The concentration of these oxygen vacancies can be controlled by the annealing temperature. We optimized the all-inorganic QLEDs with HfOx as the HTL by changing the annealing temperature. The optimized QLEDs with HfOx as the HTL showed a maximum luminance and current efficiency of 66,258 cd/m2 and 9.7 cd/A, respectively. The fabricated all-inorganic QLEDs exhibited remarkable stability, particularly when compared to devices using organic materials for the HTL. Under extended storage in ambient conditions, the all-inorganic device demonstrated a significantly enhanced operating lifetime (T50) of 5.5 h, which is 11 times longer than that of QLEDs using an organic HTL. These results indicate that the all-inorganic QLEDs structure, with ITO/MoO3/HfOx/QDs/ZnMgO/Al, exhibits superior stability compared to organic-inorganic hybrid QLEDs. [ABSTRACT FROM AUTHOR]

This work reports on the possibility of sustaining a stable operation of polarization-doped InGaN light emitters over a particularly broad temperature range. We obtained efficient emission from InGaN light-emitting diodes between 20 K and 295 K and from laser diodes between 77 K and 295 K under continuous wave operation. The main part of the p-type layers was fabricated from composition-graded AlGaN. To optimize injection efficiency and improve contact resistance, we introduced thin Mg-doped layers of GaN (subcontact) and AlGaN (electron blocking layer in the case of laser diodes). In the case of LEDs, the optical emission efficiency at low temperatures seems to be limited by electron overshooting through the quantum wells. For laser diodes, a limiting factor is the freeze-out of the magnesium-doped electron blocking layer for temperatures below 160 K. The GaN:Mg subcontact layer works satisfyingly even at the lowest operating temperature (20 K). [ABSTRACT FROM AUTHOR]

Materials exhibiting thermally activated delayed fluorescence (TADF) based on transition metal complexes are currently gathering significant attention due to their technological potential. Their application extends beyond optoelectronics, in particular organic light‐emitting diodes (OLEDs) and light‐emitting electrochemical cells (LECs), and include also photocatalysis, sensing, and X‐ray scintillators. From the perspective of sustainability, earth‐abundant metal centers are preferred to rarer second‐ and third‐transition series elements, thus determining a reduction in costs and toxicity but without compromising the overall performances. This review offers an overview of earth‐abundant transition metal complexes exhibiting TADF and their application as photoconversion materials. Particular attention is devoted to the types of ligands employed, helping in the design of novel systems with enhanced TADF properties. [ABSTRACT FROM AUTHOR]

Chiral 2D and quasi-2D hybrid organic–inorganic perovskites (HOIPs) are emerging as promising materials for a variety of applications principally related to optoelectronics and spintronics, thanks to the combined benefits deriving from both the chiral cation and the perovskite structure. Since its recent birth, this research field is tremendously growing, focalizing on the chemical composition tuning to unveil its influence on the related functional properties as well as on developing devices for practical applications. In this review, we focused on the properties of 2D and quasi-2D chiral HOIPs, firstly providing an overview on their chiroptical behaviour followed by their potential exploitation in devices investigated so far for various applicative fields. [ABSTRACT FROM AUTHOR]

Stretchable optoelectronic devices are typically realized through a 2D integration of rigid components and elastic interconnectors to maintain device performance under stretching deformation. However, such configurations inevitably sacrifice the area ratio of active components to enhance the maximum interconnector strain. We herein propose a 3D buckled height-alternant architecture for stretchable OLEDs that enables the high active-area ratio and the enhanced maximum strain simultaneously. Along with the optimal dual serpentine structure leading to a low critical buckling strain, a pop-up assisting adhesion blocking layer is proposed based on an array of micro concave structures for spatially selective adhesion control, enabling a reliable transition to a 3D buckled state with OLED-compatible processes. Consequently, we demonstrate stretchable OLEDs with both the high initial active-area ratio of 85% and the system strain of up to 40%, which would require a lateral interconnector strain of up to 512% if it were attained with conventional 2D rigid-island approaches. These OLEDs are shown to exhibit reliable performance under 2,000 biaxial cycles of 40% system strain. 7 × 7 passive-matrix OLED displays with the similar level of the initial active-area ratio and maximum system strain are also demonstrated. Conventional stretchable optoelectronics suffer from sacrificed area ratio of active components to enhance maximum strain. Here, the authors develop a 3D buckled height-alternant architecture, allowing high initial active-area ratio and maximum system strain in displays with reliable performances. [ABSTRACT FROM AUTHOR]

Emerging nano-kirigami/origami technology enables the flexible transformations of 2D planar patterns into exquisite 3D structures in situ and has aroused great interest in the areas of nanophotonics and optoelectronics. This paper briefly reviews some milestone research and breakthrough progresses in nano-kirigami/origami from the aspects of stimuli approaches and application directions. Versatile stimuli for kirigami/origami, including capillary force, residual stress, mechanical force, and irradiation-induced stress, are introduced in the micro/nanoscale region. Appealing optical applications and reconfigurable schemes of nano-kirigami/origami structures are summarized, offering effective routes to realize tunable nanophotonic and optoelectronic devices. Future challenges and promising pathways are also envisioned, including design methods, innovative materials, multi-physics field driving, and reprogrammable devices. [ABSTRACT FROM AUTHOR]

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This document is a collection of featured articles in the field of optoelectronics. Optoelectronics involves the study and development of electronic devices that emit or detect light, including gamma rays, X-rays, ultraviolet, infrared radiation, and visible light. The articles cover a range of topics, including a new passive optical network system, performance evaluation of a PET scanner, the design of a high-Q perfect absorber, the evolution of bioamplifiers, optical chaos communication, threshold voltage shift in OFETs, near-infrared CMOS image sensors, interface functionalization in perovskite solar cells, and the visualization of halide segregation in perovskite materials. These articles provide valuable insights and advancements in the field of optoelectronics. [Extracted from the article]

This paper presents a test methodology to facilitate the measuring processes of LiDAR receiver ICs by avoiding the inherent walk error issue. In a typical LiDAR system, a costly laser diode driver emits narrow light pulses with fast rising edges, and the reflected pulses from targets enter an optical detector followed by an analog front-end (AFE) circuit. Then, the received signals pass through the cascaded amplifiers down to the time-to-digital converter (TDC) that can estimate the detection range. However, this relatively long signal journey leads to the significant decline of rising-edge slopes and the output pulse spreading, thus producing inherent walk errors in LiDAR receiver ICs. Compensation methods requiring complex algorithms and extra chip area have frequently been exploited to lessen the walk errors. In this paper, however, a simpler and lower-cost methodology is proposed to test LiDAR receiver ICs by employing a high-speed buffer and variable delay cells right before the TDC. With these circuits, both START and STOP pulses show very similar pulse shapes, thus effectively avoiding the walk error issue. Additionally, the time interval between two pulses is easily determined by varying the number of the delay cells. Test chips of the proposed receiver IC implemented in a 180-nm CMOS process successfully demonstrate easier and more accurate measurement results. [ABSTRACT FROM AUTHOR]

PbS semiconductor nanocrystals (NCs) have been heavily explored for infrared optoelectronics but can exhibit visible-wavelength quantum-confined optical gaps when sufficiently small (⌀ = 1.8–2.7 nm). However, small PbS NCs traditionally exhibited very broad ensemble absorption linewidths, attributed to poor size-heterogeneity. Here, harnessing recent synthetic advances, we report photophysical measurements on PbS ensembles that span this underexplored size range. We observe that the smallest PbS NCs pervasively exhibit lower brightness and anomalously accelerated photoluminescence decays—relative to the idealized photophysical models that successfully describe larger NCs. We find that effects of residual ensemble size-heterogeneity are insufficient to explain our observations, so we explore plausible processes that are intrinsic to individual nanocrystals. Notably, the anomalous decay kinetics unfold, surprisingly, over hundreds-of-nanosecond timescales. These are poorly matched to effects of direct carrier trapping or fine-structure thermalization but are consistent with non-radiative recombination linked to a dynamic surface. Thus, the progressive enhancement of anomalous decay in the smallest particles supports predictions that the surface plays an outsized role in exciton–phonon coupling. We corroborate this claim by showing that the anomalous decay is significantly remedied by the installation of a rigidifying shell. Intriguingly, our measurements show that the anomalous aspect of these kinetics is insensitive to temperature between T = 298 and 77 K, offering important experimental constraint on possible mechanisms involving structural fluctuations. Thus, our findings identify and map the anomalous photoluminescence kinetics that become pervasive in the smallest PbS NCs and call for targeted experiments and theory to disentangle their origin. [ABSTRACT FROM AUTHOR]

In this paper, tri-phase Fe2O3–MgO–CuO nanocomposites (NCs) and pure CuO, Fe2O3 and MgO nanoparticles (NPs) were prepared using sol–gel technique. The physical properties of the prepared products were examined using SEM, XRD, and UV–visible. The XRD data indicated the formation of pure CuO, Fe2O3 and MgO NPs, as well as nanocomposite formation with Fe2O3 (cubic), MgO (cubic), and CuO (monoclinic). The crystallite size of all the prepared samples was calculated via Scherrer's formula. The energy bandgap of CuO, Fe2O3 and MgO and Fe2O3–MgO–CuO NCs were computed from UV–visible spectroscopy as following 2.13, 2.29, 5.43 and 2.96 eV, respectively. The results showed that Fe2O3–MgO–CuO NCs is an alternative material for a wide range of applications as optoelectronics devices due to their outstanding properties. [ABSTRACT FROM AUTHOR]

This article presents the classification of optoelectronics encoder faults in a permanent magnet synchronous motor (PMSM) drive system. This paper proposes the deep neural networks (DNNs) speed sensor faults classification application in the vector-controlled PMSM drive. This approach to the issue has not been discussed in the literature before. This work presents a solution based on early detection with the use of the model reference adaptive system (MRAS) estimator and fault classification based on artificial intelligence. The innovative nature of this work is also due to the simulation of speed sensor damage using the developed optoelectronics encoder model in the Matlab/Simulink environment. This work is focused on simulation studies, which have been supported by experimental results obtained on the MicroLabBox platform. This article compares two structures of deep neural networks in fault detection. The results were also compared with previous experimental studies on the classification of speed sensor failures using shallow neural networks. [ABSTRACT FROM AUTHOR]

Symmetry-deficient two-dimensional (2D) layered materials induce a highly anisotropic optical response due to the anisotropy in their crystal structure, facilitating their application in polarized nanodevices. Intercalation is a new way to tune the optoelectronic properties of materials by inserting guest atoms into layered host materials, and 2D layered structures stacked with van der Waals gaps are a prerequisite for this phase of the technique. In this paper, 2D tellurium nanosheets were synthesized with a hydrothermal method, and copper atoms were inserted with a wet chemical method. The widening of the crystal plane spacing proves the introduction of copper atoms, and polarization−related second-harmonic-generation (SHG) studies reveal the intrinsic anisotropic modes of the two samples, and birefringent properties are found with polarizing light microscopy. We further investigated the electrical properties of the samples, and the embedding of the copper atoms caused the samples to exhibit higher currents, but their devices lost the gate control effect. [ABSTRACT FROM AUTHOR]

In this paper, the performance of Cu-(In,Ga)-S2 (CIGS2) solar cells with adjusting composite [Cu]/([Ga] + [In]) (CGI)-ratio absorber was explored and compared through an improved three-stage co-evaporation technique. For co-evaporating CIGS2 absorber as a less toxic alternative to Cd-containing film, we analyzed the effect of the CGI-ratio stoichiometry and crystallinity, and explored its opto-electric sensing characteristic of individual solar cell. The results of this research signified the potential of high-performance CIGS2-absorption solar cells for photovoltaic (PV)-module industrial applications. For the optimal CIGS2-absorption film (CGI = 0.95), the Raman main-phase signal (A1) falls at 291 cm−1, which was excited by the 532 nm line of Ar+-laser. Using photo-luminescence (PL) spectroscopy, the corresponding main-peak bandgaps measured was 1.59 eV at the same CGI-ratio film. Meanwhile, the best conversion efficiency (η = 3.212%) and the average external quantum efficiency (EQE = 51.1% in the visible-wavelength region) of photo-electric properties were achieved for the developed CIGS2-solar cells (CGI = 0.95). The discoveries of this CIGS2-absorption PV research provided a new scientific understanding of solar cells. Moreover, this research undeniably contributes to a major advancement towards practical PV-module applications and can help more to build an eco-friendly community. [ABSTRACT FROM AUTHOR]