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In the fabrication of crystalline silicon solar cells, the contact properties between the front metal electrode and silicon are one of the most important parameters for achieving high-efficiency, as it is an integral element in the formation of solar cell electrodes. This entails an increase in the surface recombination velocity and a drop in the open-circuit voltage of the solar cell; hence, controlling the recombination velocity at the metal-silicon interface becomes a critical factor in the process. In this study, the distribution of Ag crystallites formed on the silicon-metal interface, the surface recombination velocity in the silicon-metal interface and the resulting changes in the performance of the Passivated Emitter and Rear Contact (PERC) solar cells were analyzed by controlling the firing temperature. The Ag crystallite distribution gradually increased corresponding to a firing temperature increase from 850 ∘C to 950 ∘C. The surface recombination velocity at the silicon-metal interface increased from 353 to 599 cm/s and the open-circuit voltage of the PERC solar cell decreased from 659.7 to 647 mV. Technology Computer-Aided Design (TCAD) simulation was used for detailed analysis on the effect of the surface recombination velocity at the silicon-metal interface on the PERC solar cell performance. Simulations showed that the increase in the distribution of Ag crystallites and surface recombination velocity at the silicon-metal interface played an important role in the decrease of open-circuit voltage of the PERC solar cell at temperatures of 850–900 ∘C, whereas the damage caused by the emitter over fire was determined as the main cause of the voltage drop at 950 ∘C. These results are expected to serve as a steppingstone for further research on improvement in the silicon-metal interface properties of silicon-based solar cells and investigation on high-efficiency solar cells.

The reactions between Ag pastes containing two types of PbO-based glass frits and an n-type (100) Si wafer during firing in air at 800 °C were investigated in order to understand the mechanism for the formation of inverted pyramidal Ag crystallites at the Si interface as well as the effect of the PbO content of the glass frit on Ag crystallite formation. Inverted pyramidal Ag crystallites were formed by the precipitation of Ag atoms dissolved in fluidized glass during the subsequent cooling process after firing. PbO in the glass frit did not participate directly in the reaction with the Si wafer. However, its content had a strong influence on the reaction rate at the glass/Si interface and, thus, on the size and distribution of the Ag crystallites. The effect of the PbO content in the glass could be understood from the higher Ag solubility and lower viscosity of the glass at the firing temperature with increasing PbO content. Based on the experimental results, a model was proposed for the formation of Ag crystallites at the glass/Si interface during the firing process of screen-printed thick-film Ag metallization.

This study presents an environmentally friendly method for synthesizing Ag@Fe2O3 nanostructures through a hydrothermal technique that utilizes Saussurea obvallata leaf extract as a reducing and capping agent. The material was characterized using UV–Vis, FTIR, XRD, SEM–EDX, and TEM-SAED-line profile analysis. The UV–Vis shows a maximum absorbance peak at 380 nm, showing a band gap of 3.26 eV. FTIR analysis revealed several functional groups (vibrational modes), including 944 and 514 cm−1 (Fe–O) and 445 cm−1 (Ag–O). XRD spectra analysis confirmed the crystalline nature and, using the Scherrer equation, showed an average crystallite size of 49.57 nm. EDX confirmed the presence of only Ag, Fe, and O elements. SEM and TEM-SAED analyses revealed an echinus-like morphology with an interplanar spacing of 126 pm of the nanostructures. The photocatalytic activity of Ag@Fe2O3 was investigated through the degradation of methylene blue (MB) dye in the presence of UV–visible light irradiation. It was observed that 97.10% MB dye degradation occurred within 60 min, with the rate constant and half-life being 0.03025 min−1 and 22.90 min, respectively. It was deduced that the synergistic interaction of Ag with Fe2O3 promoted the separation of charge, significantly diminishing electron–hole recombination. This research presents plant extract as a readily available, cost-effective, and environmentally friendly way to produce highly efficient photocatalysts for degrading wastewater dye compounds.Article HighlightsThe synthesized Ag@Fe2O3 nanostructure using Saussurea obvallata leaf extract for a biogenic synthesis method shows excellent photocatalytic dye degradation of methylene blue under UV-visible light irradiation. The combination of Ag & Fe2O3nanoparticles improved the charge separation efficiency & reduced electron-hole pair recombination, leading to enhanced photocatalytic performance.The nanostructure achieved a high photocatalytic dye degradation rate of 97.10 % within 60 minutes, with a reaction rate constant & half-life of 0.03025 min⁻¹ & 22.90 min, resp. The biogenic synthesis method is a sustainable & cost-effective approach to producing efficient photocatalysts for several environmental remediations.

The current paper exhibited a green method for the manufacture of Ag-doped ZnO/CaO nanocomposites (NCPs) by the usage of Caccinia macranthera seed extract, zinc, calcium, and silver salts solution, for the first time. The chemical structure of NCPs was studied by the FT-IR technique. The XRD pattern shows a crystallite structure with an Fm3m group space and particle size of about 23 nm. The FESEM/PSA images displayed that NCPs have uniform distribution with spherical morphology. Also, the cytotoxicity of synthesized NCPs was examined on Huh-7 cells by MTT test and the IC 50 value was 250 ppm. Additionally, the photocatalytic activity of NCPs was investigated to the methylene blue MB dye degradation, which resulted in a removal of about 90% after 100 min. According to the results of the broth microdilution process, which was done to evaluate the antibacterial activity of NCPs towards gram-positive and gram-negative bacteria, the MIC values were in the range of 0.97–125 ppm.

In this work, using a simple and facile synthesis method, a co-precipitation method, an Ag-doped BiVO 4 visible-light photocatalyst was produced and then photocatalytic activity was performed to enhance the degradation of methylene red dye. The synthesized nanoparticles of Ag-doped BiVO 4 are characterized by XRD, SEM, EDX, FTIR, PL, and UV–Visible to analyze structural, morphological, and spectral properties. By employing the Debye Scherrer formulation, the average crystallite size of the synthesized NPs was calculated as 52 nm. The synthetic samples are irregular and roughly cubic. SEM images of the Ag-doped BiVO 4 show the morphological analysis of prepared NPs. Ag plays an essential quantity in reducing the amount at which photogenerated electron/hole pairs recombine, foremost to band gap decrement of up to 2.02 for indirect transitions, because of its compatible ionic radius with BiVO 4 . Although NPs are smaller in size, they have a higher surface-to-volume ratio, which familiarizes more energetic adsorption sites and increases the catalyst’s photocatalytic activity. Interestingly, the degradation efficiency of 90.8% in 125 min in a 4% Ag-doped BiVO 4 catalyst, shows the most effective results. Experiments on recycling and trapping have been accomplished to verify the stability of the improved catalyst. A 4% Ag-doped BiVO 4 catalyst’s excellent photocatalytic activity indicates the wastewater treatment applications for which it may be applied. Antimicrobial activity of pure BiVO 4 and Ag-doped BiVO 4 showed the efficient findings and observed as efficient photocatalyst for antimicrobial properties also. Graphical Abstract

The green synthesis of silver (Ag) and zinc oxide (ZnO) nanoparticles (NPs), as well as Ag/Ag2O/ZnO nanocomposites (NCs), using polar and apolar extracts of Chlorella vulgaris, offers a sustainable method for producing nanomaterials with tunable properties. The impact of the synthesis environment and the nanomaterials’ characteristics on cytotoxicity was evaluated by examining reactive species production and their effects on mitochondrial bioenergetic functions. Cytotoxicity assays on PC12 cells, a cell line originated from a rat pheochromocytoma, an adrenal medulla tumor, demonstrated that Ag/Ag2O NPs synthesized with apolar (Ag/Ag2O NPs A) and polar (Ag/Ag2O NPs P) extracts exhibited significant cytotoxic effects, primarily driven by Ag+ ion release and the disruption of mitochondrial function. However, it is more likely the organic content, rather than size, influenced anticancer activity, as commercial Ag NPs, despite smaller crystallite sizes, exhibit less effective activity. ZnO NPs P showed increased reactive oxygen species (ROS) generation, correlated with higher cytotoxicity, while ZnO NPs A produced lower ROS levels, resulting in diminished cytotoxic effects. A comparative analysis revealed significant differences in LD50 values and toxicity profiles. Differentiated PC12 cells showed higher resistance to ZnO, while AgNPs and Ag/Ag2O-based materials had similar effects on both cell types. This study emphasizes the crucial role of the synthesis environment and bioactive compounds from C. vulgaris in modulating nanoparticle surface chemistry, ROS generation, and cytotoxicity. The results provide valuable insights for designing safer and more effective nanomaterials for biomedical applications, especially for targeting tumor-like cells, by exploring the relationships between nanoparticle size, polarity, capping agents, and nanocomposite structures.

AZO/Ag/AZO multilayer structures were grown at room temperature on glass and quartz substrates with different Ag layer thicknesses using confocal RF magnetron sputtering. Microstructural, morphological and optoelectronic properties of the AZO/Ag/AZO multilayer structures were studied as a function of Ag thickness and substrate type. Grazing incidence X-ray diffraction (GIXRD) analysis shows that the AZO/Ag/AZO structures for both substrates are polycrystalline and have preferential growth of ZnO (002) and Ag (111). In addition, the thickness of the Ag layer and the nature of substrate affect crystallinity and crystallite size. Atomic force microscopy (AFM) studies show that the structures on quartz substrate have reduced surface roughness and increased crystallite size, with the smoothest surface at 7 nm Ag thickness. The optical measurements show that the multilayer structures deposited on glass substrate have better transmission than those on quartz and the average transmission strongly depends on the Ag thickness, while the optical bandgap increases with Ag thickness in the range of 3.56–3.65 eV for both substrates. The photoluminescence (PL) spectra of all samples show a decrease in UV emissions with increasing Ag thickness. Hall Effect measurements show that the electrical properties of AZO/Ag/AZO structures on both substrates are improved by increasing the Ag thickness. The multilayer structures on glass substrate demonstrate a better figure of merit for the considered thickness, with a best value of 1.34 × 10 –3 Ω −1 achieved with 10 nm Ag thickness and a low resistivity of 7.98 × 10 –5 Ω cm and a good average transmittance of 61.5%.

This study presents findings related to the characterization of cubic SnS (π-SnS) thin films and p-SnS/n-Si heterojunction structures produced simultaneously using the ultrasonic spray pyrolysis technique. In this context, the impact of different spray solution flow rates on the morphological, structural, optical, and electrical characteristics of the films was examined. Morphological analyses revealed that higher flow rates resulted in films with denser and smoother surfaces, approximately 6 nm in roughness. Additionally, it was observed that both the thickness and the growth rate of the films could be adjusted through the modulation of the flow rate. Structural analyses determined that the crystallite size increased and micro-strain values decreased with increasing flow rates. Optical evaluations indicated a decline in the optical band gap of the thin films from about 1.8 eV to 1.7 eV as the flow rates increased. This trend was consistently observed in the data obtained using the Tauc method and the derivative of transmission with respect to wavelength versus photon energy graphs. Electrical analyses revealed that the resistivity values of the thin films increased from 5.24 × 10 5 Ωcm to 1.64 × 10 6 Ωcm with increasing flow rates. Furthermore, I-V analyses of the Au/p-SnS/n-Si/Ag heterojunction structures indicated significant variability in key electrical properties. The saturation currents displayed a broad range, suggesting varying efficiencies in charge carrier collection across different samples. Similarly, the change of ideality factors pointed to differences in charge transport mechanisms, while the shifts in barrier heights indicated changes in junction properties with different fabrication conditions. The results of this study offer valuable perspectives for future research.

Dye-sensitized solar cells (DSSCs) have emerged as a potential candidate for third-generation thin film solar energy conversion systems because of their outstanding optoelectronic properties, cost-effectiveness, environmental friendliness, and easy manufacturing process. The electron transport layer is one of the most essential components in DSSCs since it plays a crucial role in the device’s greatest performance. Silver ions as a dopant have drawn attention in DSSC device applications because of their stability under ambient conditions, decreased charge recombination, increased efficient charge transfer, and optical, structural, and electrochemical properties. Because of these concepts, herein, we report the synthesis of pristine TiO2 using a novel green modified solvothermal simplistic method. Additionally, the prepared semiconductor nanomaterials, Ag-doped TiO2 with percentages of 1, 2, 3, and 4%, were used as photoanodes to enhance the device’s performance. The obtained nanomaterials were characterized using XRD, FTIR, FE-SEM, EDS, and UV–vis techniques. The average crystallite size for pristine TiO2 and Ag-doped TiO2 with percentages of 1, 2, 3, and 4% was found to be 13 nm by using the highest intensity peaks in the XRD spectra. The Ag-doped TiO2 nanomaterials exhibited excellent photovoltaic activity as compared to pristine TiO2. The incorporation of Ag could assist in successful charge transport and minimize the charge recombination process. The DSSCs showed a Jsc of 8.336 mA/cm2, a Voc of 698 mV, and an FF of 0.422 with a power conversion efficiency (PCE) of 2.45% at a Ag concentration of 4% under illumination of 100 mW/cm2 power with N719 dye, indicating an important improvement when compared to 2% Ag-doped (PCE of 0.97%) and pristine TiO2 (PCE of 0.62%).

Silver nanoparticles have been widely used to treat bacterial infections on wounds. Chitosan is a natural polymer having good biocompatibility and biodegradability. Chitosan have antibacterial effects and are largely used in healthcare practices to cure wounds. In this scenario, an attempt was made to biologically synthesize AgNPs using the chitosan extracted from shrimp shell waste. The synthesized Ch-AgNPs exhibited strong UV absorption spectra at 404 nm. XRD spectrum confirmed the presence of nanocrystals with an average crystallite size of 26 nm. HR-TEM images have shown spherical shaped particles with the size ranging between 10 and 50 nm. Ch-AgNPs exhibited antibacterial activity in a dose-dependent manner and greater activity was observed against P. aeruginosa . The zone of inhibition against P. aeruginosa was 10, 15 and 20 mm at 25, 50 and 100 µg mL −1 , respectively. The zone of inhibition against MRSA was 8, 15 and 18 mm at 25, 50 and 100 µg mL −1 respectively. Ch-AgNPs effectively inhibited the biofilm of MRSA and P. aeruginosa at 100 µg mL −1 . In addition, Ch-AgNPs coated band-aid cloth showed greater antibacterial activity compared to uncoated band-aid cloth. Furthermore, Ch-AgNPs exhibited anticoagulant activity by inhibiting the coagulation of human blood for 24 h.