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Perovskite material synthesis and thin film preparation, along with optimization of properties, will go a long way toward reducing data disparities. The optimal composition management of various elements of perovskite remains outstanding research. This study explores experimental approaches for preparing and optimizing the microstructure of halide perovskites using solution processing. We experimented with different ways to make the materials and adjust their properties to find the best conditions for chemical and material production. The results showed that the crystallization of the halide perovskite began at an optimal temperature of 70 °C, suggesting this is the ideal temperature for perovskite formation. The crystallite sizes of the samples varied from 23.67 nm to 55.79 nm, with all samples exhibiting an absorption onset near 850 nm, corresponding to an energy gap of approximately 1.55 eV. The findings of this study offer valuable insights for optimizing the synthesis process of perovskite-based devices, leading to enhanced performance. Furthermore, the results provide a basis for explaining the effective optimizations of synthesis conditions and material properties. [ABSTRACT FROM AUTHOR]

Self‐healing polyvinyl alcohol‐polyacrylic acid (PVA‐PAA) composite films incorporated with molecular iodine (I2) are presented for optoelectronic applications. The incorporation mechanism between the PVA‐PAA donor and I2 acceptor is investigated by studying the chemical, crystal, and morphological properties of the composite films. Incorporating PVA‐PAA composite films with I2 decreases the crystallinity degree of the composite films, which increases the electrical conductivity by enabling the segmental motion in the polymer matrix. PVA‐PAA/I2 composite films are stable at temperatures lower than 200°C, where the majority of optical, optoelectronic, and electrical applications can be realized. Additionally, introducing I2 into the PVA‐PAA matrix increases the melting temperature of the composite films. Moreover, the optical and electrical properties of the PVA‐PAA/I2 composite films are investigated. The bandgap energy of PVA‐PAA film is 3.88 eV, decreasing continuously to 3.38 eV as I2 concentration increases to 16 wt.%. On the other hand, The average conductivity of the PVA‐PAA film is 7.46×10−6S×cm−1. Increasing I2 concentration in the PVA‐PAA matrix increases the electrical conductivity continuously up to 1.33×10−4S×cm−1. The physical properties of the PVA‐PAA/I2 composite films exhibit self‐healing properties after thermal treatment and UV irradiation that occur during the operation cycling in optical, optoelectronic, and electrical applications. [ABSTRACT FROM AUTHOR]

This paper presents an optoelectronic transceiver (OTRx) realized in a 180 nm CMOS technology for applications of short-range LiDAR sensors, in which a modified current-mode single-ended VCSEL driver (m-CMVD) is exploited as a transmitter (Tx) and a voltage-mode fully differential transimpedance amplifier (FD-TIA) is employed as a receiver (Rx). Especially for Tx, a concurrent automatic power control (APC) circuit is incorporated to compensate for the inevitable increase in the threshold current in a VCSEL diode. For Rx, two on-chip spatially modulated P+/N- well avalanche photodiodes (APDs) are integrated with the FD-TIA to achieve circuit symmetry. Also, an extra APD is added to facilitate the APC operations in Tx, i.e., concurrently adjusting the bias current of the VCSEL diode by the action of the newly proposed APC path in Rx. Measured results of test chips demonstrate that the proposed OTRx causes the DC bias current to increase from 0.93 mA to 1.42 mA as the input current decreases from 250 µApp to 3 µApp, highlighting its suitability for short-range sensor applications utilizing a cost-effective CMOS process. [ABSTRACT FROM AUTHOR]

Traditionally, CMOS is not considered a light emitting device. Similar to laser or LED, and microwave devices, Photonic Millimeter Wave CMOS transistors are both light as well as microwave emitting devices. Ever since AMD releases the 64-bits Athlon processor in around 2005–2006, the clock speed race for ASIC and processors has been stopped. Wireless tools always replace wired electronic tools. The very large number (trillions) and multiple layers of metal wires seen in ASICs and ULSI significantly slow down the processors. Using microwave photonic CMOS and wireless ULSI, clock speed races may resume, reaching far beyond 6G wireless generations. [ABSTRACT FROM AUTHOR]

The study of two-dimensional (2D) materials has attracted considerable attention from material scientists globally, mainly because of their distinct electronic, spintronic, magnetic, and optoelectronic characteristics. Transition metal dichalcogenides (TMD) and dihalides (TMDH) are two examples of 2D materials. This study investigates the structural stability, phonon dispersion, electronic, optical, and thermodynamic properties of the unique trigonal osmium diiodide (OsI 2 ) monolayer, which is an example of TMDH. The well-established Density Functional Theory (DFT) is employed for this purpose. We identified an indirect bandgap semiconductor property in this monolayer. The energy bandgap values for GGA-PBE, GGA-PBEsol, and the hybrid functional HSE06 were found to be 1.72, 1.56, and 2.86 eV, respectively. The compound OsI 2 demonstrates structural stability, and studies of phonon dispersion indicate that there are no virtual (negative) phonon frequencies. Furthermore, OsI 2 demonstrates optical absorption within the visible spectrum, making it suitable for optoelectronic applications. However, thermodynamic property calculations have shown that the synthesis of the OsI 2 monolayer would occur naturally at temperatures lower than room temperature, as evidenced by the free energy estimates. [ABSTRACT FROM AUTHOR]

We investigate the comprehensive analysis's structural, electronic, optical, and elastic properties of Cs₂NaScX₆ (X = Cl, Br) double perovskites using density functional theory (DFT) implemented by the WIEN2k code. The results show that both compounds are in cubic phases. The calculated tolerance factors show both are stable compounds. The computed optimized lattice parameters are Cs₂NaScX₆ (X = Cl, Br) are 10.72 Å and 12.01 Å, respectively. Employing a modified Becke–Johnson (mBJ) potential electronic nature shows that both compounds are in semiconductor nature, that is, 3.138 eV and 3.977 eV. The calculated elastic constant and perimeters show the Cs₂NaScX₆ (X = Cl, Br) are mechanical stables and also ductile and anisotropic nature. The optical properties described the range of photon energies from 0 to 10 eV, revealing pronounced absorption within the visible spectrum, highlighting their considerable promise for transformative innovations in photovoltaic technology. These double perovskites exhibit superior absorption characteristics compared to their Cs₂NaScX₆ (X = Cl, Br) analogues, thus laying the groundwork for significant advancements in solar energy conversion and photovoltaic applications. [ABSTRACT FROM AUTHOR]

The optoelectronic light sensor device (photodetector) is fabricated using a composite of silver iodide and poly-2-aminobenzenethiol-intercalated iodide ion nanowires (AgI/P2ABT-I NW-C). This device boasts a straightforward fabrication process consisting of only two steps and is characterized by promising nanowires that indicate a high density of active sites. This feature contributes to achieving a desirable bandgap of 1.92 eV. The optoelectronic devices exhibit exceptional sensitivity and efficiency across a range of photon frequencies and energies, from 3.6 to 2.3 eV. Particularly noteworthy is their performance under the influence of high kinetic energy photons within this range. The responsivity (R) and detectivity (D) values demonstrate a consistent behavior, declining linearly from 0.96 to 0.90 mA/W and from 0.21*109 to 0.20*109 Jones, respectively. Moreover, the corresponding photocurrent (Jph) values for photons with energies between 3.6 and 2.3 eV fall within the range of − 0.094 to − 0.089 mA.cm−2. These promising results recommend the application of this optoelectronic device in both industrial and commercial sectors. Its ease of fabrication and cost-effectiveness further enhance its appeal for widespread adoption. With its impressive sensitivity and efficiency characteristics, the device holds considerable promise for various applications, ranging from advanced industrial processes to consumer electronics. [ABSTRACT FROM AUTHOR]

The novel molybdenum oxide iodide/poly-o-aminobenzenethiol (MoO2I2/POABT) nanocomposite thin film presents a promising solution for advanced light sensing and captures in optoelectronic devices. This thin film is fabricated through a two-step process: first, the oxidation of o-aminobenzenethiol using iodide, followed by a reaction with Na2MoO4, leading to the integration of MoO2I2 within the POABT matrix. The resulting film has a notable bandgap of 2.2 eV, a tube-shaped morphology with a diameter of 150 nm, and a crystalline size of 119 nm, making it ideal for use as a light sensor and optoelectronic device. Device sensitivity is evaluated using linear sweep voltammetry under light exposure. The photocurrent density (Jph) reaches 0.88 mA/cm², with a photocurrent of 0.28 mA/cm². Sensitivity testing across various photon energies and wavelengths shows peak Jph values at 340 nm and 440 nm, with strong performance at 540 nm and 730 nm. Noteworthy photoresponsivity (R) is observed at 340 nm and 440 nm, with values of 8.0 and 7.4 mA/W, respectively. Additional R values of 6.3 and 6.0 mA/W are noted at 540 and 730 nm. The highest detectivity (D) values are recorded at 340 nm and 440 nm, measuring 0.181 × 10¹⁰ and 0.167 × 10¹⁰ Jones, while lower D values of 0.142 × 10¹⁰ and 0.135 × 10¹⁰ Jones are seen at 540 nm and 730 nm, respectively. The MoO2I2/POABT nanocomposite thin film shows great potential for commercial and industrial optoelectronic applications with its excellent reproducibility, strong performance metrics, and simple and scalable fabrication process. [ABSTRACT FROM AUTHOR]

Dion–Jacobson‐type 2D halide perovskites (DJPs) present an ideal alternative to their 3D counterparts due to their superior stability and exceptional optoelectronic properties. Despite the numerous DJPs proposed in recent years, the impact of different spacer cations on DJPs remains unclear. This understanding is crucial for researchers to select suitable materials and is an urgent requirement for the development of higher‐performance DJPs‐based devices. In this study, the influence of the chain‐like spacer cations with varying branch chains and chain lengths is thoroughly examined using both theoretical and experimental methods. The findings reveal that spacer cations with high polarity components along the main chain direction enhance the stability and photoelectric properties of DJPs. Additionally, it is found that the chain length of the spacer cation plays a critical role. Chain lengths that are too long or too short can detrimentally affect the photoelectric performance and stability of DJPs. These insights will guide researchers in selecting suitable spacer cations and in innovating new types of DJPs. [ABSTRACT FROM AUTHOR]

Organic photovoltaic cells (OPVs) are a promising low‐cost renewable energy technology. Among various semiconductors studied for OPVs, boron subphthalocyanine chloride (Cl‐BsubPc) is one of the most explored. Phenoxy‐substituted BsubPc (PhO‐subPc) is an analogue of Cl‐BsubPc that introduces an axial phenoxy ligand in order to tune its electronic properties. In this paper, the effects of halogen substitution on the optoelectronic properties of PhO‐subPc are discussed in terms of the nature, number, and location of halogen atoms. DFT calculations show that the peripheral halogen substitutions significantly decrease the exciton binding energy value, increase the reorganization energy value, and also improve the light‐harvesting efficiency of the mentioned molecules. These modifications are symptoms of improved exciton separation and charge transport; hence, the peripherally halogenated PhO‐subPc are those that exhibit the best performances. However, the phenoxy‐substituted BsubPc do not enhance the performance of the boron subphthalocyanine chloride as far as the hole transport materials (HTM) of organic solar cells are concerned. [ABSTRACT FROM AUTHOR]

Organic excess electron compounds with significant nonlinear optical (NLO) properties are widely employed in optoelectronic applications. Herein, single-alkali metals with diaza[2.2.2] cryptand (M@crypt,M=Li, Na, and K) are investigated for optoelectronic and NLO properties by using the density functional theory. Thermodynamic and kinetic stabilities of present complexes are computed through interaction energy (Eint) and ab-initio molecular dynamic (AIMD) simulations. M@crypt complexes carry excess electrons and mimic molecular electrides. Quantum theory of atoms in molecules (QTAIM) analysis and reduced density gradient (RDG) spectra demonstrate the roles of the weak van der Waals (vdW) interactions between metal and complexant. The remarkable hyperpolarizability (βo) value up to 1.41 × 106 au may be credited to the presence of loosely bound excess electrons. The hyper Rayleigh scattering hyperpolarizability (βHRS) is recorded up to 1.31 × 106 au for the K@crypt. Furthermore, frequency-dependent first-order and second-order hyperpolarizability is more prominent at the applied frequency of ω = 0.042823 au. The electron localizing function (ELF) and localized orbital locator (LOL) analysis further disclose the nature of interaction between alkali metal and complexant. The TD-DFT method is adopted to get excited state parameters and absorbance properties. An electron density difference map (EDDM) is exploited to evaluate the orbital contributions in excited states. Hence, the studied electride may become a promising candidate for NLO materials. We anticipate that the present work will provide insight into further development of molecular electride for optoelectronic applications. IMPACT STATEMENT: Organic electrides M@cryptand [2.2.2] (where M=Li, Na, and K) are examined as excess electrons, where vdW forces play important roles in promoting the NLO properties. [ABSTRACT FROM AUTHOR]

High frying quality in terms of frying colour is an important trait for potatoes meant for French fry production. Determination of frying colour is often performed visually, which might be affected by biases and is therefore less suitable for research. Available laboratory methods also lack the capability to cover the whole sample and distinguish between tuber parts. Additionally, sample destruction is often required for colour analysis. Therefore, a new approach using RGB colour values and the subsequent R/G ratio of French fries to assess frying colour was tested in this research. Over the course of 3 years, 673 samples of the cultivar Innovator were assessed and compared to visual scoring, and some samples were also assessed for glucose content. A high correlation of R2 = 0.8346 between the visual scoring and the optoelectronic assessment was found for 633 samples. The validation data set of 40 samples reached a correlation of R2 = 0.7850 with the implemented model. These results show that French fry frying colour can be described using the R/G ratio. This promising approach is suitable for other researchers as well as industry professionals with further research. [ABSTRACT FROM AUTHOR]

Density Functional Theory (DFT) is incorporated in this study to examine the thermodynamic, electronic, mechanical, and optical characteristics of antiperovskite compounds A3BO (A = K, Rb and B = Au, Br). The purpose of the study is to demonstrate a comprehensive understanding of these materials and their potential applications across various fields emphasizing their stability and energetic profiles. The electronic properties, including band structures, and density of states are also analyzed to understand the electrical behavior of these materials, which enables predicting their conductive and semiconductor nature. The band gaps of K3AuO, K3BrO, Rb3AuO, and Rb3BrO are 0.72 eV, 0.80 eV, 0.15 eV, and 0.29 eV, respectively. The study also investigated the mechanical properties of the antiperovskite structures, including elastic constants, bulk modulus, and shear modulus to provide insights into their mechanical stability and durability. Their Pugh's ratio (B/G) is below 1.75 and negative Cauchy pressure indicates these compounds are brittle. And machinability index B/C44 > 1.5 implies excellent lubricating properties. This phenomenon extends the potential industrial application of materials with specific mechanical integrity to their structural components. Additionally, the study investigated the optical properties of the A3BO antiperovskite compounds, including the dielectric function, loss function, reflectivity, conductivity, refractive index, and absorption spectra. These findings provide a comprehensive understanding of how these materials interact with light, which could be useful in the development of optoelectronic devices. Overall, this DFT study provides significant insights into the multifaceted properties of A3BO antiperovskite compounds, laying the groundwork for further experimental exploration and facilitating the targeted design of materials with tailored properties for specific technological applications. [ABSTRACT FROM AUTHOR]

Abstract Perovskite material synthesis and thin film preparation, along with optimization of properties, will go a long way toward reducing data disparities. The optimal composition management of various elements of perovskite remains outstanding research. This study explores experimental approaches for preparing and optimizing the microstructure of halide perovskites using solution processing. We experimented with different ways to make the materials and adjust their properties to find the best conditions for chemical and material production. The results showed that the crystallization of the halide perovskite began at an optimal temperature of 70 °C, suggesting this is the ideal temperature for perovskite formation. The crystallite sizes of the samples varied from 23.67 nm to 55.79 nm, with all samples exhibiting an absorption onset near 850 nm, corresponding to an energy gap of approximately 1.55 eV. The findings of this study offer valuable insights for optimizing the synthesis process of perovskite-based devices, leading to enhanced performance. Furthermore, the results provide a basis for explaining the effective optimizations of synthesis conditions and material properties.

Abstract Through the DFT computations, the structural, vibrational, electronic, elastic, optical and thermal (thermoelectric, thermodynamic) properties of the two-dimensional Rb2Te monolayer are briefly contemplated. The Perdew-Bruke-Ernzerhof (PBE) form of generalized gradient approximation (GGA) functional in WIEN2k was deployed for the analysis of all these material properties. The trigonally crystallizing monolayer with an indirect band gap of 1.72 eV may be an upright single-layer that suffices distinct applications. ‘No negative’ phonon bands confirm the dynamical stability of the monolayer. The Rb2Te monolayer has large indirect band gap than Rb2S and Rb2Se. It exhibits mechanical stability with positive elastic constants satisfying the Born-Huang criterion for two-dimensional materials. The absorption coefficient spanning largely in the ultra-violet range makes the monolayer a congruous material for UV applications. Also, the thermoelectric figure of merit for p-type Rb2Te single-layer at room temperature is high (0.67) compared to the analogous series of compounds, that makes the monolayer a viable one for thermoelectric flexibility and experimental synthesis. The monolayer has high hole effective mass and D ratio. The obtained results aids in revealing the outstanding properties and excellent stability of the monolayer. Based on these findings the Rb2Te monolayer paves the way for promising applications in the fields of photovoltaics, thermoelectrics and UV-based applications.

Abstract We report the fabrication and characterization of a Bi(III) oxide/polypyrrole (Bi2O3/Ppy) nanocomposite thin film optoelectronic photodetector synthesized by a simple one-pot method. The nanocomposite consists of spherical Bi2O3 nanoparticles embedded in a Ppy matrix, forming a porous structure with a high surface area. The XRD analysis reveals that the Bi2O3 nanoparticles have a poly-crystalline nature with a crystal size of 40 nm and an optical bandgap of 2.86 eV. The SEM images show that the nanoparticles are agglomerated into clusters of about 100 nm in diameter, with pores of about 200 nm in width. The device exhibits a high sensitivity to light, as evidenced by the increase of the photocurrent density (Jph) from − 0.06 mA.cm−2 in the dark to -0.12 mA.cm−2 under illumination at -2.0 V. The device also shows a wavelength-dependent response, with the highest responsivity (R) of 1.0 and 0.9 mA/W and detectivity (D) of 0.221 × 109 and 0.20 × 109 Jones at photon energies of 3.6 eV and 2.8 eV, respectively. The Bi2O3/Ppy nanocomposite is a promising material for low-cost, high-performance optoelectronic applications, making it a superior choice over many contemporary devices reported in recent literature.

This research provides numerical exploration of the dynamic stability, microstructural, elastic, magneto-electronic, and optical properties of CoYFeAl, CoYMnAl, and CoYCrAl compounds with 3d and 4d elements of quaternary Heusler compounds via first-principles computations. According to the findings, these compounds are mechanically and dynamically stable in type (I) structure and ferromagnetic phase, and they are hard materials based on their computed elastic, cohesive, and formation energies. Our investigation highlights the structural properties, which are in good agreement with other numerical simulations. The electronic properties show that the CoYMnAl and CoYCrAl compounds have half-metal behavior, supported by high Curie temperatures and integer total magnetic moments equal to 4 μB and 3 μB, respectively. For the third compound, CoYFeAl, a metallic ferromagnetic character is predicted for this material with a total magnetic moment close to zero. The magnetism of the compounds CoYMnAl and CoYCrAl is mostly due to the cobalt, manganese, and chromium atoms' 3d electrons. The CoYMnAl and CoYCrAl compounds exhibit narrow indirect semiconductor band gaps in the Γ - L line of 0.741 eV and 0.746 eV, respectively. A small half-metallic gap equal to 0.373 eV and 0.558 eV has been found, respectively, for CoYMnAl and CoYCrAl, indicating that these compounds could be promising candidates for spintronic applications. This numerical exploration is the first of its kind in terms of optical properties. Our findings have revealed that the CoYMnAl and CoYCrAl compounds exhibit strong absorption and can be used in future optoelectronic applications through a wide energy range of the light spectrum. In the absence of experimental data and the limited availability of theoretical investigations, the present exploration can pave the way for future studies into the potential use of these compounds in modern electronics, optoelectronics, spintronics, and conversion and harvesting energy applications intended for socioeconomic needs. [ABSTRACT FROM AUTHOR]

Abstract A polypyrrole-bismuth tungstate (Ppy-Bi2WO6) core-shell nanocomposite (n-type material) has been developed on a layered Ppy (p-type) base as an efficient light-capturing material exhibiting photodiode behavior. This device demonstrates promising sensitivity for light sensing and captures across a broad spectral range, from near IR to UV. The Bi2WO6/Ppy nanocomposite boasts an optimal bandgap of 2.0 eV, compared to 3.4 eV for Ppy and 2.5 eV for Bi2WO6. The crystalline size of the core-shell composite is approximately 21 nm, emphasizing its photon absorption capabilities. The composite particles, around 100 nm in length, feature a highly porous morphology that effectively traps incident photons. The performance of this optoelectronic device is evaluated using current density (J) measurements under light (Jph) and dark (Jo) conditions. In darkness, the n-p type semiconductor exhibits limited current with a Jo of −0.22 mA cm−2 at 2.0 V. When exposed to white light, the Ppy- Bi2WO6/Ppy device generates hot electrons, achieving a Jph value of 1.1 mA/cm−2 at 2.0 V. It shows a superior responsivity (R) of 6.6 mA/W at 340 nm, gradually decreasing to 6.3 mA/W at 440 nm and 4.2 mA/W at 540 nm, indicating high sensitivity across the UV-Vis spectrum. At 730 nm, the R-value is 2.6 mA/W, highlighting its sensitivity in the near IR region. Additionally, at 340 nm, the device achieves a detectivity (D) value of 0.15 × 10¹⁰ Jones, which decreases with longer wavelengths to 0.14 × 10¹⁰ Jones at 440 nm, 0.9 × 10⁹ Jones at 540 nm, and 0.63 × 10⁹ Jones at 730 nm. With its great stability, low cost, easy fabrication, and potential for mass production, this optoelectronic light sensor and photodiode device holds significant promise for industrial applications as a highly effective optoelectronic device.

Abstract Ab-initio simulations using density functional theory (DFT) were employed to investigate the structural, mechanical, electronic, magnetic, optical, and thermoelectric properties of halide perovskites $$\hbox {BaCoX}_3$$ (X = Cl, Br, I). Structural optimization and mechanical stability assessments confirm the reliability of these perovskites in a hexagonal P $$6_3$$ mc symmetry. The stability of the ferromagnetic phase was validated through total crystal energy minimization via Murnaghan’s equation of state. Electronic band structures and density of states, derived from the generalized gradient approximation (GGA), reveal a semiconducting ferromagnetic nature in the spin up channel, spotlighting their potential in semiconductor spintronic applications. Phonon dispersion analysis of $$\hbox {BaCoCl}_3$$ and $$\hbox {BaCoBr}_3$$ revealed positive phonon modes throughout the entire Brillouin zone, confirming their dynamical stability. In contrast, $$\hbox {BaCoI}_3$$ demonstrated dynamical instability. The elastic constants confirm the mechanical stability and ductile nature of the perovskites. Optical and dielectric properties of these perovskites show significant UV absorption and photoconductivity, making them highly suitable for optoelectronic and solar cell applications. Finally, transport properties, such as the Seebeck coefficient, electrical conductivity, thermal conductivity, power factor, and figure of merit (ZT) unveil their exceptional thermoelectric performance. Combining half-metallic ferromagnetic traits with superior thermoelectric and optoelectronic performance positions $$\hbox {BaCoX}_3$$ compounds as exceptional candidates for applications in spintronics, optoelectronics, and thermoelectrics. This comprehensive investigation demonstrates their ability to excel across a diverse array of advanced technological applications.

Abstract Photonic integrated circuits (PICs) represent a promising technology for the much-needed medical devices of today. Their primary advantage lies in their ability to integrate multiple functions onto a single chip, thereby reducing the complexity, size, maintenance requirements, and costs. When applied to optical coherence tomography (OCT), the leading tool for state-of-the-art ophthalmic diagnosis, PICs have the potential to increase accessibility, especially in scenarios, where size, weight, or costs are limiting factors. In this paper, we present a PIC-based CMOS-compatible spectrometer for spectral domain OCT with an unprecedented level of integration. To achieve this, we co-integrated a 512-channel arrayed waveguide grating with electronics. We successfully addressed the challenge of establishing a connection from the optical waveguides to the photodiodes monolithically co-integrated on the chip with minimal losses achieving a coupling efficiency of 70%. With this fully integrated PIC-based spectrometer interfaced to a spectral domain OCT system, we reached a sensitivity of 92dB at an imaging speed of 55kHz, with a 6dB signal roll-off occurring at 2mm. We successfully applied this innovative technology to obtain 3D in vivo tomograms of zebrafish larvae and human skin. This ground-breaking fully integrated spectrometer represents a significant step towards a miniaturised, cost-effective, and maintenance-free OCT system.

This study presents a finite element model (FEM) simulation of optoelectronic stimulation in the rat brain, designed to investigate the effects of this emerging neural stimulation technique. A detailed 3D model of the rat brain and an equivalent circuit representation of the organic semiconductor-based stimulation device was used to simulate the subdural application of optoelectronic stimuli to the rat brain. The model is based on realistic electrode geometries and material properties. The stimulated brain volume is approximately 38 mm3 with a maximal stimulation depth of 2.6 mm. Our results indicate that optoelectronic stimulation can achieve targeted activation of cortical neurons. Further studies will focus on optimizing device parameters, exploring long-term effects, and expand this approach for specific neural bioelectronics to fully exploit its potential in clinical applications.

Flexible polymer nanocomposite composed of organic methylcellulose (MC) and semiconducting titanium dioxide (TiO2) films were successfully prepared. The energy dispersive X-ray spectroscopy (EDX) and Fourier transform infrared spectroscopy (FTIR) recorded the structure characteristics of the films, proving that MC/TiO2 nanocomposite were successfully synthesized. The EDX showed that this composite was composed of (28.55% C, 50.90% O, and 20.55% Ti), which displayed the chemical composition of MC/TiO2. Moreover, the scanning electron microscope (SEM) shows the TiO2 nanoparticles are loaded homogenously in the nanocomposite films. With increasing the TiO2, the FTIR intensity of most peaks gradually decreased which may be attributed to that titanium dioxide nanoparticles (TiO2 NPs) were formed on the methylcellulose (MC). The UV spectrophotometer records the data of absorption (A) for the MC and MC/TiO2 films between 200nm and 1100nm at the ambient temperature. Using Tauc’s relation, the linear/nonlinear optical characteristics of MC and MC/TiO2 films were computed. By mixing MC with 2%, 4%, and 6% TiO2, the Urbach energy of the MC is enhanced from 1.77eV to 1.85, 2.02, and 2.34eV, correspondingly, while the TiO2 reduced the energy gap of MC from 5.17eV to 3.59, 3.52, or 3.43eV. Moreover, the carbon cluster increased from 44 for MC to 92, 95, and 101 for MC mixed by 2%, 4%, and 6% TiO2. This study found the MC/TiO2 hybrid films can potentially be used as optical materials for flexible electronic devices. [ABSTRACT FROM AUTHOR]