Shape Effects on Light Absorption and Scattering for Nanoparticles in Thin Organic Films

A systematic study on the absorption enhancement by embedding metallic Nano Particles (NPs) in the Copper Phthalocyanine (CuPc) thin films has been reported. The Surface Plasmon resonance (SPR) can be excited by the addition of metal nano particles directly. Consequently, the incident light can be more focused and folded into the CuPc thin organic layers. The light scattering, and absorption have been applied on three shapes of silver nano particle (i.e. cylinder, hemisphere, and cross) by utilization of the Finite Different Time Domain (FDTD) software and the effect of change of NP size on the amount of light scattered and absorbed has been investigated. Finally, the effect of light absorption in organic solar cell performance u

Determination of thermodynamic properties of CrH, NiC and CuLi diatomic molecules with the linear combination of Hulthen-type potential plus Yukawa potential

In this work, we investigate the thermodynamic properties of CrH, NiC and CuLi diatomic molecules with a linear combination Hulthen and Yukawa potentials in the presence and absence of magnetic and Aharanov-Bohm (AB) fields. The Schrodinger equation in 3D and 2D were solved using the Nikiforov-Uvarov (NU) method and the exact quantization rule (EQR) respectively. To determine the thermodynamic properties for the selected diatomic molecules, we first used the energy spectrum to evaluate the partition function and other thermodynamic functions such as entropy, Helmholtz free energy, internal energy and specific heat capacity. In addition, it is found that in the classical limit, the specific heat capacity saturates for large values of the principal quantum number, nmax for the selected diatomic molecules at a fixed temperature except CrH. Our results can be applied to molecular physics and chemical physics

Exact solutions of κ-dependent Schrödinger equation with quantum pseudo-harmonic oscillator and its applications for the thermodynamic properties in normal and superstatistics

The effects of the curvature parameters on the energy eigenvalues and thermodynamic properties of quantum pseudoharmonic oscillator are investigated within the framework of nonrelativistic quantum mechanics. By employing Nikiforov-Uvarov method, the energy spectra are obtained and used to study the ordinary statistics and q-deformed superstatistics as a function of temperature in the presence and absence of the curvature parameters. It is shown that the q-deformed supertatistics properties of the quantum pseudoharmonic oscillator reduce to the ordinary statistical properties in the absence of the deformation parameter. Finally, our results are illustrated graphically to show the behaviour of the energy spectra and thermodynamic properties for the three curvature parameters:κ=−1,κ=1andκ=0

Photocatalytic Degradation of Methyl Green Dye Mediated by Pure and Mn-Doped Zinc Oxide Nanoparticles under Solar Light Irradiation

Herein this study, pure and manganese- (Mn-) doped ZnO (2 wt. %) nanoparticles have been synthesized using the chemical precipitation method and characterized for the photodegradation of methyl green (MG) pollutant dye under natural sunlight. The structural analysis via XRD patterns has revealed that both intrinsic and Mn-doped ZnO (2 wt. %) samples have hexagonal wurtzite structures with appropriate phase purity, clearly indicating the absence of any external impurity. The incorporation of Mn in the host ZnO lattice has decreased the crystallite size (21.10 → 18.76 nm), and nanoparticle-type surface features with sizes in the 50–100 nm range have been observed through FESEM-based surface morphological studies. Both aforementioned observations have merit in providing more active area and a high surface area to volume ratio for photocatalytic reaction. The investigation of photophysical properties indicates that in Mn-doped ZnO nanoparticles, the absorption peak is blue-shifted by 5 nm (365 → 360 nm), due to the widening of the bandgap. The degradation kinetics of MG dye follow the pseudo-second-order kinetics, and the degradation efficiency has been observed to be 62.78% mediated by pure ZnO and 66.44% by Mn-doped ZnO (2 wt. %) photocatalyst under 60 minutes of sunlight irradiation. Specifically, the rate of photocatalytic reaction (K) ~0.01792 min-1 and R2~0.97992 has been achieved for pure ZnO, whereas slightly higher (K) ~0.02072 min-1 and R2~0.97299 have been observed for Mn-doped ZnO, respectively. Conclusively, the synergistic interactions with multiple charge transfer pathways, improvement of e−/h+ pair charge separation, improved surface area, and efficient generation of hydroxyl radicals are supposed to be responsible for the highly efficient photocatalytic activity of the Mn–doped ZnO photocatalyst for MG dye

Influence of relative humidity on the electrical response of PEDOT:PSS based organic field-effect transistor

We have investigated the influence of relative humidity on the electrical response of a bottom gate organic field-effect transistor (OFET) with poly(3,4-ethylenedioxythiophene)/poly(4-styrene sulfonate) (PEDOT:PSS) as an active channel material. For sensor fabrication, the organic polymer PEDOT:PSS has been spun-cast on highly doped n-Si wafer with preliminary thermally deposited gold, source and drain electrodes. The structural characterization and surface morphology study of active layer has been performed by XRD and FESEM, respectively. From the transfer characteristic curve, the p-type hole conductivity in PEDOT:PSS thin film is confirmed. Whereas from the output current-voltage (I–V) characteristic of the OFET, the Ion/Ioff ratio has been measured to be ∼2.6, when operated at relative humidity (RH) ∼60%. The humidity sensing characteristics of the OFET have further been investigated by exposing the proposed OFET to varied RH levels (40–80% RH) at room temperature (26.2 °C). Within the humidity range examined, the channel current has been observed to amplify by nearly 29.4 times of its magnitude

Organic humidity sensing film optimization by embedding inorganic nano-anatase TiO2 powder

In this work, surface-type humidity sensors with P3HT (organic) and P3HT–TiO2 (organic–inorganic hybrid) active layers have been fabricated. The surface morphology of the humidity active films has been studied by atomic force microscopy, whereas their crystalline structure has been studied by X-ray diffraction. We have aimed at improving the sensing parameters of P3HT-based humidity sensor, by embedding nano-anatase TiO2 powder in pristine organic P3HT moiety. The capacitance versus relative humidity (%RH) response curves of the organic and hybrid humidity sensors have been examined in 30–98%RH range (dark ambient condition, room temperature). In general, an increase in capacitance has been observed in both sensors with the increment in RH level. The observed response of both humidity sensors is believed to be associated with polarization change due to the adsorption of water molecules and transfer of charge carriers due to the formation of charge transfer complexes. The hybrid-based humidity sensor has shown significantly improved humidity-sensing parameters, i.e., fivefold higher sensitivity, with hysteresis reduced to one-third as compared to that of pristine organic humidity sensor. A relatively faster response and recovery time has also been obtained by the hybrid sample