Ghulam Ishaq Khan Institute of Engineering Sciences and Technology

About: Ghulam Ishaq Khan Institute of Engineering Sciences and Technology is a education organization based out in Topi, Pakistan. It is known for research contribution in the topics: Thin film & Quantum efficiency. The organization has 618 authors who have published 940 publications receiving 10674 citations.

Electrical and Interfacial Properties of p-Si/P3HT Organic-on-Inorganic Junction Barrier

Abstract: The electrical characterization of the Al/p-Si/P3HT/Ag organic-on-inorganic diode was done by current– voltage, capacitance–voltage and conductance–voltage methods. The values of ideality factor and barrier height of the diode were determined from the current–voltage characteristics and found as 2.32 and 0.77 eV, respectively. These values were also determined from Cheung’s functions and Norde’s method due to the non-ideal behavior of the diode. The electronic parameters obtained from the various methods indicate a good consistency with each other. The density of interface states for Al/p-Si/P3HT/Ag organic-on-inorganic diode was found to be 7.64 × 10 cm−2 eV−1. The obtained electrical parameters of the Al/p-Si/P3HT/Ag organic-on-inorganic diode are higher than that of the conventional Ag/p-Si Schottky diodes. This indicates that the electrical properties of the silicon Schottky diodes can be controlled using organic interfacial layer.

Dye-Sensitized Solar Cells Based on Porous Hollow Tin Oxide Nanofibers

Abstract: Porous hollow tin oxide (SnO2) nanofibers and their composite with titanium dioxide (TiO2) particles (Degussa P25) were investigated as a photoanode for dye-sensitized solar cells. Incorporation of TiO2 particles in porous hollow SnO2 fibers enhanced the power conversion efficiency ( $\eta )$ from 4.06% to 5.72% under 100-mW/cm $^{2}$ light intensity. The enhancement of efficiency was mainly attributed to increase in current density ( $J_{\rm sc}$ ) and improvement in fill factor (FF). Increase in $J_{\rm sc}$ was caused by higher dye loading as indicated by UV–Vis absorption spectra and the improvement in FF was attributed to faster charge transport time as obtained from transient analysis. The microstructure of SnO2 fibers was studied using transmission electron microscope, scanning electron microscope, and X-ray diffraction. The electron transfer and recombination life times were studied using transient analysis, whereas interfacial charge transfer was studied using electrochemical impedance spectroscopy.

The electrical characterization of Ag/PTCDA/PEDOT:PSS/p-Si Schottky diode by current–voltage characteristics

Abstract: The Ag/PTCDA/PEDOT:PSS/p-Si Schottky diode has been fabricated by adding a layer of organic compound 3,4,9,10-perylene tetracarboxylic dianhydride (PTCDA) on top of the p-Si for which the junction characteristics have been investigated. The electronic properties of the device have been studied by the conventional I–V and the Norde's methods. For conventional I–V measurements the rectifying behavior has been observed with a rectification ratio of 236. The barrier height and ideality factor values of 0.81 eV and 3.5, respectively, for the structure have been obtained from the forward bias I–V characteristics. Various electrical parameters such as reverse saturation current, series resistance and shunt resistance have been calculated from the analysis of experimental I–V results and discussed in detail. The barrier height and the series resistance determined by the Norde's function are found in good agreement with the values calculated from conventional I–V measurements. The charge conduction mechanism has also been discussed.

A carbon nanotube-based pressure sensor

Abstract: In this study, a carbon nanotube (CNT)-based Al/CNT/Al pressure sensor was designed, fabricated and investigated. The sensor was fabricated by depositing CNTs on an adhesive elastic polymer tape and placing this in an elastic casing. The diameter of multiwalled nanotubes varied between 10 and 30 nm. The nominal thickness of the CNT layers in the sensors was in the range ~300–430 μm. The inter-electrode distance (length) and the width of the surface-type sensors were in the ranges 4–6 and 3–4 mm, respectively. The dc resistance of the sensors decreased 3–4 times as the pressure was increased up to 17 kN m−2. The resistance–pressure relationships were simulated.