Gold nanoparticles were synthesized via surfactant-free laser ablation and incorporated into electrospun bamboo/poly(vinyl alcohol)/chitosan nanofibers for plasmonic photocatalysis. Comprehensive characterization via FE-SEM, FTIR, Raman, TGA, and UV–Vis spectroscopy revealed the synergistic integration of renewable bamboo biocomponents with laser-ablated Au nanoparticles. At pH 10, Bamboo/Au/PVA/CS-2 nanofibers achieved 70.55% methylene blue degradation in 240 min, a 1.8-fold improvement over the PVA/CS baseline (50.27%), with a pseudo-first-order rate constant of 0.0038 min−1. Radical scavenger experiments confirmed that superoxide radicals (∙O₂−) and photogenerated holes (h+) are the dominant reactive species, thereby elucidating the SPR-assisted charge-transfer mechanism. These results demonstrate that bamboo-derived, Au-modified PVA/CS nanofibers represent a promising class of eco-friendly, plasmon-enhanced photocatalysts for sustainable water treatment, establishing an innovative platform for colloid-interface engineering in environmental remediation.

Silver (Ag) and titanium dioxide (TiO₂) nanostructures were synthesized by femtosecond laser ablation (800 nm, 1 kHz) and incorporated into a polyacrylonitrile (PAN)/collagen blend via electrospinning to obtain functional nanofibrous membranes. The study comprised three stages: nanoparticle synthesis, nanofiber fabrication and characterization, and evaluation of photocatalytic performance. UV–Vis spectroscopy of TiO₂@Ag nanoparticles showed a gradual decrease in absorbance from the ultraviolet to infrared region and an estimated band gap of ∼2.5 eV. FTIR analysis (500–3000 cm−1) confirmed successful incorporation of TiO₂@Ag into the PAN/collagen matrix, while SEM revealed uniform nanofibers with an average diameter of ∼100 nm. Photocatalytic activity was assessed by the degradation of methylene blue under light irradiation. The PAN/collagen/TiO₂/Ag nanofibers exhibited markedly improved photodegradation efficiency, highlighting the role of nanofiber architecture and plasmon-enhanced photocatalysis in developing advanced materials for wastewater treatment.

This study presents a comprehensive SCAPS-1D simulation of an ultra-thin CIGSe/CdS/i-ZnO/ITO solar cell with a 420 nm absorber layer, focusing on the influence of key physical parameters and back surface field engineering. The effects of acceptor doping density in CIGSe (N_a = 10¹³ to 10¹⁸ cm⁻³), interface defect density (N_i–t = 10⁹ to 10¹⁸ cm⁻³), bulk defect density (N_t = 10¹² to 10²⁰ cm⁻³), and electron affinity (χ = 4.35–4.65 eV) were systematically investigated. Increasing N_a significantly enhanced device performance by strengthening the internal electric field and increasing the carrier concentration, thereby improving V_oc, fill factor, and efficiency. In contrast, elevated interface and bulk defect densities led to severe recombination losses and significant degradation of all photovoltaic parameters. Optimal band alignment was obtained at χ ≈ 4.35 eV, corresponding to a slight negative conduction-band offset that facilitates carrier transport and suppresses recombination. Recombination analysis showed stable performance of the radiative recombination coefficient over the range 10⁻¹⁶ to 10⁻⁸ cm³ s⁻¹, while Auger recombination became dominant at coefficients above 10⁻²³ cm⁶ s⁻¹. Among the investigated back surface field layers, Cu₂O provided the best performance due to its wide band gap (2.2 eV) and strong back-surface electric field, yielding a maximum simulated efficiency of ∼40.3% with V_oc = 0.817 V, J_sc = 30.03 mA cm⁻², and FF = 82.88%. Capacitance–voltage and Mott–Schottky analyses revealed that capacitance increases from 57.6 to 109.9 nF cm⁻² with increasing N_a, and the built-in potential ranges from 0.80 to 1.32 V, confirming enhanced junction properties. These results provide practical guidelines for optimizing ultra-thin CIGSe solar cells through defect control, band alignment tuning, and back surface field design.

The present study reports a hierarchical supercapacitor electrode that integrates poly(2-aminothiophenol) (P2-ATH) with a cobalt–nickel heterostructure comprising cobalt carbonate hydroxide hydrate (CCHH) and cobalt-nickel oxide (CNO). The hybrid is synthesized by hydrothermal growth of CCHH/CNO nanoneedles, followed by in situ oxidative polymerization of P2-ATH to yield conformal nanoflakes. This interpenetrating architecture furnishes a porous, electrically percolated network that shortens ion-diffusion paths and accelerates electron transport, thereby coupling the redox activity of P2-ATH with the multiple Faradaic sites of the Co–Ni phase. Electrochemical tests in different electrolytes (NaOH, NaCl, and HCl) demonstrate a strong electrolyte dependence, with 0.5 M HCl yielding the best performance. At 0.4 A g⁻¹, the specific capacitance reaches 113.87 F g⁻¹ in HCl, compared with 27.89 F g⁻¹ in NaOH and 7.73 F g⁻¹ in NaCl. In 0.5 M HCl, the electrode delivers an energy density of 5.69 Wh kg⁻¹ at a specific power of 479.7 W kg⁻¹. The results highlight the synergistic interplay between the conductive P2-ATH and the Co–Ni nanoneedle, establishing P2-ATH/CNO-CCHH as a promising platform for high-rate, durable supercapacitors and broader electrochemical energy-storage applications.

In this study, ultrathin CuIn_xGa_1-xSe₂ (CIGS) films with two distinct thicknesses were grown on n-Si substrates by pulsed laser deposition (PLD), with thickness controlled by varying the number of laser pulses. Au plasmonic nanoparticles were subsequently incorporated into the CIGS layers using the same PLD technique for photodetection applications. Owing to the localized surface plasmon resonance (LSPR) induced by the embedded Au nanoparticles, photon absorption within the CIGS layers was significantly enhanced across the visible and NIR spectral regions. Increasing the film thickness in the presence of Au nanoparticles promoted the formation of larger grains and yielded notable improvements in crystallinity. The dark electrical behavior of plasmonic and non-plasmonic p-CIGS/n-Si heterojunctions was analyzed using the conventional J–V method, as well as the Cheung–Cheung and Norde methods. Key diode parameters, including barrier height, ideality factor, and series resistance, were extracted and comparatively evaluated. Among the studied devices, the Au-CIGS2A heterojunction (based on Au-embedded CIGS thin film produced with 86,400 laser pulses) exhibited the most ideal diode characteristics, whereas the CIGS1A device (based CIGS thin film produced with 43,200 laser pulses) demonstrated the least favorable electrical performance. Under illumination, the combined effect of increased CIGS thickness and the LSPR-driven optical enhancement provided by the Au nanoparticles resulted in higher photovoltaic conversion efficiency in the corresponding heterojunction diodes.

Co-/Cu-co-doped ZnO nanorods are synthesized by electrochemical deposition to investigate the effect of co-doping on their structural, optical, electronic, and electrochemical properties. XRD, Raman, SEM, and photoluminescence analyses reveal that Co/Cu incorporation modifies the ZnO lattice, increases defect-related states, and reduces the band gap from 3.11 to 2.15 eV. Density functional theory calculations further show that Co 3d and Cu 3d states appear near the Fermi level and contribute to the observed band-gap narrowing. Electrochemical measurements indicate that the co-doped nanorods exhibit the lowest charge-transfer resistance and the highest areal capacitance among the samples studied. Together, these results show that Co/Cu co-doping improves charge-transfer kinetics in ZnO nanorods and highlights co-doping as an effective strategy for tuning oxide electrodes for energy-storage applications.

In the present work, an essential advance in the preparation of novel nanocomposites based on functionalized V₂O₅ nanostructures with reduced graphene oxide by hydrothermal method, which has great potential for use in photocatalytic processes related to environmental remediation. XRD analysis confirmed V₂O₅ in an orthorhombic structure. SEM images showed transparent RGO layers well anchored onto the surface of the V₂O₅ with a homogeneous distribution. Raman spectroscopy further explained the hybridization and interaction between the components. The photocatalytic activity of Rhodamine-B in aqueous solutions has been studied upon irradiation with visible light. A high RhB degradation was obtained using the V₂O₅/RGO photocatalyst (82 %), compared to the degradation obtained with only V₂O₅ (60 %). First-principles Density Functional Theory (DFT) simulations reveal a strong interaction between V₂O₅ molecules and graphene surfaces, with an adsorption energy of −1.673 eV and a significant charge transfer of 0.367 e− to RGO. This interaction modifies the electronic structure, creating semi-metallic behavior near the Fermi level and enhancing catalytic activity through improved charge carrier dynamics and active sites for photocatalytic applications.

The effect of the Gd/Sn composition ratio of Cu₂Sn_1-xGd_xS₃ is examined. The films are fabricated on glass substrates in a sulfur atmosphere via the spin coating. The influence of the Gd/Sn composition ratio on the structural, morphological, optical, and electrical properties of the films is investigated using X-ray diffraction, FESEM, UV-Vis, and Hall effect. XRD patterns for the films revealed that all films have a monoclinic polycrystalline. The morphological and optical properties of the films show the formation of spherical grains and polygonal structures with an energy band in the range of 2.10–1.50 eV. The electrical properties of the films are changed by increasing the Gd/Sn composition ratio in the film. Furthermore, the Cu₂Sn_1-xGd_xS₃/CdS heterojunction solar cell was modeled by SCAPS-1D. The optimized conditions yielded exceptional photovoltaic parameters, achieving an open-circuit voltage of 0.7885 V, short circuit current density of 41.09 mA/cm², fill factor of 85.30%, and an efficiency of 27.3%.

In this study, we developed a ternary nanocomposite using graphene oxide (GO), multiwalled carbon nanotubes (MWCNTs), and tungsten trioxide (WO₃), nanostructures, synthesized via a straightforward chemical process with ultrasound assistance. The initial composition was GO/MWCNT, later combined with WO₃ to form the GO/MWCNT: WO₃ (25/25:50) structure. Characterization was performed using X-ray diffraction, which revealed the multiphase nature of the WO₃ nanostructures. Scanning Electron Microscopy showed the one-dimensional CNTs interwoven with graphene oxide sheets decorated with densely populated WO₃ nanopetals. Fourier transform infrared and Raman spectroscopy confirmed the chemical composition of the system. The photocatalytic degradation of Rhodamine-B in water under visible light irradiation was significantly enhanced using the GO/MWCNT: WO₃ nanocomposite, achieving an 85 % degradation rate compared to only 10 % by GO alone, highlighting its potential for environmental remediation.

The novel design of gold/polypyrrole-multi-walled carbon nanotubes/titanium dioxide/aluminum oxide/P-type silicon/aluminum (Au/PPy-MWCNTs/TiO2/Al2O3/p-Si/Al) is utilized to fabricate supercapacitors, sensors, diodes, and microelectronic devices. The electrical characteristics of the structure are examined both in the dark and under illumination to evaluate its photosensing performance. The real part of the AC conductivity at all voltages and temperatures is observed to be low at low- and mid-frequencies but significantly increases at high frequencies. The imaginary part of the AC conductivity exhibits three distinct behaviors: it is positive at low frequencies and shows both negative and positive values at high frequencies. At specific temperatures, such as 293, 273, and 253 K, the imaginary component of the AC conductivity (σ ac) is negative only at high frequencies. In the Cole-Cole diagrams, the symmetrical semicircles increase with temperature for all voltages, except at V = -2 V. The real part of the electric modulus (M′) shows positive and negative values; however, at certain temperatures, it is positive. The imaginary part of the modulus (M″) is consistently positive.

Lead-free halide perovskite, kesterite, and delafossite semiconductors were integrated into a multilayer ternary heterostructure (Cs₂ SnCl₆ /Cu₂ ZnSnS₄ /CuFeO₂) to enable direct solar-driven hydrogen production from sewage water. X-ray photoelectron spectroscopy confirms the expected elemental composition and oxidation states, while X-ray diffraction verifies the successful incorporation of all three layers with well-defined crystallinity. Optical measurements reveal a systematic narrowing of the effective band gap, decreasing from 1.73 eV for CuFeO₂ to 1.50 eV for the Cu₂ ZnSnS₄ /CuFeO₂ bilayer and further to 1.12 eV for the complete Cs₂ SnCl₆ /Cu₂ ZnSnS₄ /CuFeO₂ stack. The multilayered architecture enabled effective charge separation and transport, delivering a photocurrent density of −24.0 mA cm-2, approximately 77 times higher than the dark current density. The incident photon-to-current efficiency reaches 77%. These results demonstrate strong photoresponsivity and confirm the suitability of the multilayer heterojunction for efficient solar-driven hydrogen production. The extracted thermodynamic parameters (ΔH* = 3.452 kJ mol⁻¹ and ΔS* = 9.644 J mol⁻¹ K⁻¹) indicate a low activation barrier for interfacial charge transfer, suggesting that the system effectively couples photonic and thermal contributions to enhance hydrogen-evolution kinetics. Collectively, these findings establish the all-lead-free Cs₂ SnCl₆ /Cu₂ ZnSnS₄ /CuFeO₂ heterostructure as a highly efficient photoelectrode for solar-to-hydrogen conversion in complex wastewater environments. Demonstrating hydrogen evolution directly from sewage water further highlights the dual functionality of this architecture for simultaneous wastewater valorization and sustainable fuel production.

Tandem solar cells have a wider photon absorption range, allowing them to provide better efficiency than single-junction SC. The upper cell absorbs high-energy photons, while the lower cell absorbs low-energy filtered photons. However, in order to obtain affordable, efficient, and long-lasting SC, the absorber layers of the top and bottom cells must be integrated with an adequate bandgap. This research suggests tandem perovskite solar cells as upper band active materials in this setting. The Si homojunction solar cell's performance was improved by investigating the thicknesses of the p−type and n−type layers, doping concentrations, and defect densities. The thickness variation of the perovskite solar cell (100−400nm) is then optimized. To precisely replicate the tandem devices, the estimated spectra of the perovskite SC are optically filtered onto the lower cells. Current matching was achieved by adjusting the thickness of the perovskite sub-cell with different bottom layer thicknesses, and the optimized efficiency of 36.26% for the perovskite/Si tandem device was shown. The discoveries will open the door for the upcoming creation of high−efficiency, low-energy solar cells.