In this study, polymer solar cells were synthesized by adding Sb2S3 nanocrystals (NCs) to thin blended films with polymer poly(3-hexylthiophene)(P3HT) and 6,6-phenyl-C61-butyric-acid-methyl-ester ...(PCBM) as the p-type material prepared via the spin-coating method. The purpose of this study is to investigate the dependence of polymer solar cells’ performance on the concentration of Sb2S3 nanocrystals. The effect of the Sb2S3 nanocrystal concentrations (0.01, 0.02, 0.03, and 0.04 mg/mL) in the polymer’s active layer was determined using different characterization techniques. X-ray diffraction (XRD) displayed doped ratio dependences of P3HT crystallite orientations of P3HT crystallites inside a block polymer film. Introducing Sb2S3 NCs increased the light harvesting and regulated the energy levels, improving the electronic parameters. Considerable photoluminescence quenching was observed due to additional excited electron pathways through the Sb2S3 NCs. A UV–visible absorption spectra measurement showed the relationship between the optoelectronic properties and improved surface morphology, and this enhancement was detected by a red shift in the absorption spectrum. The absorber layer’s doping concentration played a definitive role in improving the device’s performance. Using a 0.04 mg/mL doping concentration, a solar cell device with a glass /ITO/PEDOT:PSS/P3HT-PCBM: Sb2S3:NC/MoO3/Ag structure achieved a maximum power conversion efficiency of 2.72%. These Sb2S3 NCs obtained by solvothermal fabrication blended with a P3HT: PCBM polymer, would pave the way for a more effective design of organic photovoltaic devices.
We discuss advances in the covalent modification of the carbon allotropes, in particular graphene and carbon nanotubes. The main focus is on the organometallic chemistry that affords the possibility ...to electronically interconnect graphitic surfaces by means of covalent bonding. This mode of functionalization allows the formation of atomic scale interconnects that consist of bis-hexahapto-metal-bonds between benzenoid ring systems, which increases the dimensionality of the electronic structure of the materials leading to enhanced conductivity. The bis-hexahapto bond formation in single walled carbon nanotubes (SWNTs), graphite nanoplatelets and graphene, can be readily accomplished by metal vapor synthesis (e-beam evaporation), solution and photochemical routes.
This paper investigates the effects of substrate temperature and precursor salt molarities on the nickel oxide (NiO) thin film physical properties. The NiO thin films were deposited on glass ...substrates via spray pyrolysis at different temperature (from 400 to 650 °C) with two different molarities (0.05 M and 0.1 M) of the precursor nickel acetate. The structural and morphological properties of the films were studied by X-ray diffraction (XRD), Raman spectroscopy, and scanning electron microscopy (SEM). The optical properties of the films were characterized using UV–visible transmission spectroscopy. Electronic defects were investigated using photoluminescence (PL) measurements. The obtained results reveal that regardless of the salt molarity, films prepared at low substrate temperatures are amorphous. With an increase in the substrate temperature, the film crystallinity is improved, while the grain size is enlarged but remains in the nanocrystalline range. In the intermediate temperature range of 500–600 °C, both Raman and XRD analyses suggested that the films were composed of a mixture of oxalate (NiOx) and NiO. At high substrate temperature, the obtained film is a pure NiO. Films prepared at 500 and 600 °C exhibit lower transmission in the visible region due to their large surface roughness. PL measurements revealed only the presence of Ni interstitial defect in the forbidden band gap. At low molarity, this defect concentration increases with substrate temperature, whereas it is reduced when using higher salt molarity.
We report the fabrication of copper zinc tin sulfide, Cu2ZnSnS4, nanoparticles by a solvothermal method. We synthesized a polymer matrix-based organic hybrid photovoltaic active layer using poly ...(3-hexyle thiophene) (P3HT) 6,6: phenyl-C61-butyric-acid-methyl-ester (PCBM) and Cu2Zn SnS4 (CZTS) nanoparticles (NPs). The objective of this exploration is to verify the performance dependence of polymeric solar cells on the concentration of CZTS NPs. The active layers were doped with different concentrations of CZTS NPs (0.2, 0.4, 0.6, 0.8 mg/mL) in the P3HT: PCBM polymer. The CZTS NPs and the prepared polymer active layer were characterized by different characterization methods such as: X-ray diffraction (XRD), UV–Visible spectrophotometer, transmission electron microscopy (TEM), and Fourier Transform Infrared (FTIR), Atomic force microscopy (AFM). The hybrid photovoltaic active layer was enhanced by doping with CZTS NPs, which led to an improved homogeneous structure and incremental increases in the light absorption and electrical conductivity. X-ray diffraction (XRD) results showed that the orientation of the P3HT crystallites was affected by the blend ratio within the block polymer films. A red-shift of the FTIR results was observed as the doping concentration increased. The root-mean-square value of the samples decreased from 10.95 to 0.68 nm as the CZTS NPs concentration increased, indicating improved surface roughness. The optical properties indicated the relationship between light absorption and the morphology of the active layer. Polymer solar cells with the structure ITO/ZnO/P3HT: PCBM: CZTSNPs/Ag were fabricated. The power efficiency obtained was 3.11%, with a short-circuit current density (Jsc) of 11 mA/cm2, an open-circuit voltage (Voc) of 412 mV, and a fill factor of 68.7%.These results show the role of CZTS NPs in the development of high-efficiency P3HT:PCBM polymer solar cells.
•Kesterite Cu2ZnSnS4 (CZTS) doped P3HT:PCBM based solar cells are optimized for increased efficiency.•CZTS NPs induced chain order contributes to the crystallinity of P3HT.•CZTS NPs effect carrier transport, surface roughness, and light absorption.•Optimal power conversion efficiency of 3.11% was achieved.
The increasing energy consumption in modern society requires long-term energy storage technology. The main problem for a sustainable energy storage system is energy optimization and power density. ...The vanadium copper sulfide (VCuS) was hydrothermally synthesized in this study. The electrochemical activity of the VCuS was studied with the three-cell configuration, which demonstrated a maximum capacity of 475C/g (at 1.0 A/g), higher than VS2 and CuS. The surface area for VCuS was 13.65 m2/g, estimated using the BET measurement. The conductivity of VCuS was measured to be 233 mS/cm, while 1 M KOH electrolyte shows maximum conductivity of 206 mS/cm. The supercapattery (VCuS//AC) delivers an excellent specific capacity of 163C/g having a current density of 1.0 A/g. The VCuS//AC can provide energy of 34.5 Wh/kg at 800 W/kg power density (at 1.0 A/g). Additionally, the VCuS//AC durability test measured capacity retention after subjecting it to 10,000 cycles. The VCuS//AC displayed excellent cycling stability of 80 % after 10,000 cycle repetitions.
•Vanadium-Copper-Sulfide is synthesized by hydrothermal method and used as a battery-grade electrode for supercapattery.•Outstanding specific capacity of 475 C/g is obtained.•The remarkable high-energy density of 34.5 Wh/kg at a power density of 730 W /kg is conceived.•Excellent cyclic stability of 80% capacity retention is obtained after 5000 consecutive charge-discharge cycles.
Modern spectroscopic techniques for the investigation of magnetization dynamics in micro- and nano- structures or thin films use typically microwave antennas which are directly fabricated on top of ...the sample by means of electron-beam-lithography (EBL). Following this approach, every magnetic structure on the sample needs its own antenna, resulting in additional EBL steps and layer deposition processes. We demonstrate a new approach for magnetization excitation that is suitable for optical and non-optical spectroscopy techniques. By patterning the antenna on a separated flexible glass cantilever and insulating it electrically, we solved the before mentioned issues. Since we use flexible transparent glass as a substrate, optical spectroscopy techniques like Brillouin-light-scattering microscopy ({\mu}BLS), time resolved magneto-optical Kerr effect measurements (TRMOKE) or optical detected magnetic resonance (ODMR) measurements can be carried out at visible laser wavelengths. As the antenna is detached from the sample it can be freely positioned in all three dimensions to adress only the desired magnetic sample structures and to achieve effective excitation. We demonstrate the functionality of these antennas using {\mu}BLS and compare coherently and thermally excited magnon spectra to show the enhancement of the signal by a factor of about 400 due to the excitation by the antenna. Moreover, we succeed to characterize yttrium iron garnet thin films with spatial resolution using optical ferromagnetic resonance (FMR) experiments. We analyse the spatial excitation profile of the antenna by measuring the magnetization dynamics in two dimensions. The technique is furthermore applied to investigate injection-locking of spin Hall nano-oscillators.
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