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: Quantum efficiency & Diode. The organization has 618 authors who have published 940 publications receiving 10674 citations.

Correction: Compositional engineering of the pi-conjugated small molecular VOPcPhO : Alq3 complex to boost humidity sensing

Abstract: Correction for ‘Compositional engineering of the pi-conjugated small molecular VOPcPhO : Alq3 complex to boost humidity sensing’ by Noshin Fatima et al., RSC Adv., 2017, 7, 19780–19786.

Dual function Li-reactive coating from residual lithium on Ni-rich NCM cathode material for Lithium-ion batteries.

Abstract: In this study, lithium phosphate (Li3PO4) is coated on the surface of Ni-rich LiNi0.91Co0.06Mn0.03O2 cathode material to enhance its cyclability and rate performance. The process is carried-out by achieving dual benefits, reduction of residual lithium compounds by converting them into Li3PO4 coating material. The 0.1 mol.% Li3PO4 (LiP) sample exhibits a capacity retention of 82% while the pristine NCM shows only 68.1% after 100 cycles. In addition, the LiP-0.1 NCM delivers high discharge capacities (161.9 mAh g-1 at 3C, 144.3 mAh g-1 at 4C and 94.6 mAh g-1 at 5C) as compared to the pristine NCM (129.3 mAh g-1 at 3C, 67.4 mAh g-1 at 4C and 33.4 mAh g-1 at 5C) in the voltage range of 3.0-4.3 V. In addition, the irreversible phase transition has also suppressed in the coated sample which is confirmed by cyclic voltammetry. Our study suggests that Li3PO4 coating reduces the polarization and acts as protecting layer between the electrode and electrolyte that results in the superior electrochemical performance.

Photo Organic Field Effect Transistor´s Properties

Abstract: A thin organic films of p-type semiconducting copper phthalocynanine (CuPc) film and semitransparent Al film were deposited in sequence by vacuum evaporation on glass substrate with Ag source and drain electrodes, fabricating an organic field effect transistor with metal (aluminum)-semiconductor (copper phthalocyanine) Schottky junction The transistor was investigated for effect of illumination on its characteristics It was found that the gate-source (Al-Ag) and gate-drain (also Al-Ag) dark currentvoltage characteristics show rectification behavior Under non-modulated filament-lamp illumination, photo-potential is developed between gate-source and gate-drain terminals Drain current of this organic phototransistor (OPT) increased with illumination An energy band diagram of the Al-CuPc junction and the equivalent circuit diagram of the OPT were produced

Comparative study of impedance spectroscopy and photovoltaic properties of metallic and natural dye based dye sensitized solar cells

Abstract: Photoelectrical characterization and impedance spectroscopy are performed for Dye sensitized solar cells (DSSC) fabricated by using natural dye (Pomegranate extract) and metallic dye (N719). Dyes are characterized by ultraviolet–visible spectroscopy to study optical properties. Typical photovoltaic behaviors are observed with open circuit voltage of 0.52 and 0.7 V and short circuit current density of 0.34 and 14 mA/cm2 for natural and metallic dyes based cells respectively. From current–voltage (I-V) measurements, fill factor, conversion efficiency and ideality factor are extracted. Electrical properties of the cells are investigated using Mott-Schottky plots. To gain insight into charge transport, voltage and frequency dependent impedance spectroscopy is performed. Photovoltaic performance of cells is evaluated from the trends of recombination resistance and chemical capacitance in the measured impedance spectra. Significant contribution of interface trap states is observed at low frequencies and reversal of the polarity of capacitance from positive to negative values is observed at higher frequencies. The overall behavior of devices is compared. To our knowledge these impedance spectroscopy results for natural dye based solar cell are not reported earlier. Their insight and understanding is important for optimizing various components and interfaces for the development of cost effective commercially available natural dyes based DSSCs.