Raghubir singh Anand

Ikjot Energy International Private Limted · Limited Company

Aluminum doped zinc oxide thin films have been prepared by sputtering under argon gas pressure of 0.15 Pa at different radio frequency (RF) power densities to optimize the conditions for application in both bottom emitting and transparent OLEDs. The films exhibit a wurtzite-type hexagonal structure with the [0001] preferred orientation and optical...

To increase solar based electricity generation, it is desired that more & bigger solar based power plants be set up across the country to substitute the utility power coming from exhaustible and polluting fuels. To this effect, our government has resolved to establish 100000 MWp solar PV based power plants by 2022, a target biggest world over. The...

The study discusses the short-term performance variations of grid-connected photovoltaic (PV) systems installed in Kanpur, India. The analysis presents a holistic view of the performance variations of three PV array technologies [multi-crystalline (multi-Si), copper indium gallium diselenide and amorphous silicon] and two inverter types (high-frequ...

Tröger's Base (TB) scaffold has been exploited to create two novel novel amorphous hole-transporting materials (HTMs), i.e., TB1 and TB2, with high Tgs (152-156 °C) as alternatives to the popular NPB (Tg ~ 95 °C). The hole-transporting properties of both TB1-2 are shown to be comparable to or better than that of NPB by contrasting the results of de...

An attempt has been made to prepare Al-doped ZnO thin films by rf sputtering at different argon pressures and low substrate temperatures of 80–95 °C to ascertain the conditions rendering optical and electrical characteristics useful for their applications in photovoltaic devices. The increase in argon pressure is shown to influence their morphology...

Abstract The present article reports the polymer light-emitting diode property of the nanocomposite comprising poly 9,9-dioctyl fluorene-alt-bithiophene and reduced graphene oxide used as an emissive layer. Two times repetition of Hummers oxidation and hydrazine hydrate reduction method produce reduced graphene oxide (term as rGO2) with more unifor...

A series of fluorescent teraryls and quateraryls was prepared from a ketene-S,S-acetal under mild conditions. These compounds exhibited blue, skyblue and green color emission both in solid state and in solution phase with good quantum yields, positive solvatochromic behaviour and reversible oxidation and reduction properties. The electronic charact...

Optically transparent and electrically conducting aluminum-doped zinc oxide thin films of thickness 110, 350, and 500 nm have been deposited on unintentionally heated glass substrates by the radio frequency magnetron sputtering method to investigate their structural and optoelectrical properties. All thin films are shown to exhibit: 1) wurtzite-typ...

Simple molecular structures capable of emitting over the entire visible range are still a challenge. Planar molecular structures have the drawback of fluorescence quenching in the solid state thus limiting their application fields. Combining long range excimer/exciplex emissions with a compound emission have been used to get white light. In this wo...

Most grid-connected photovoltaic inverters in the Indian market are designed based on European standards and have not been tested in the Indian climate. In this paper, the performances of eight photovoltaic inverters from three different manufacturers connected to a 40 kW grid-connected solar plant are assessed. Four photovoltaic topologies namely...

Indium tin oxide thin films (thickness ~ 300 nm) have been deposited on glass at the substrate temperature of 65 °C by radio frequency magnetron sputtering with the power density of 1.25 W cm− 2 under argon atmosphere and annealed subsequently in silicon oil at 200° and 350 °C to investigate systematically the effects on their structural, optical a...

For an OLED, its electrodes and organic film stack determine its performance. In this paper, we study the effect of acidic (Sulfuric acid) and basic (Sodium Hydroxide) ITO surface treatments. Resistance variation, roughness variation and etc. are recorded. Their effect on device performance is studied by fabricating OLED of m-MTDATA/NPB/Alq3/BCP/Li...

A series of solution processable blue fluorescent, 3, 3' linked carbazole based linear conjugated molecules (1-5) have been synthesized with phenyl, ethynylene, and ethynylphenyl spacer. Their photophysical, electrochemical and thermal properties have been studied to elucidate their structure property relationship. These chromophores have high ther...

Solar electricity supply system has grown at very rapid pace in India during the last few years. A total of 1047.84 MW of grid connected photovoltaic projects and 160.8 MW of off-grid systems have been commissioned under different policy mechanisms between January 2010 and November 2012. It is observed that solar capacity development has achieved a...

A novel series of light emitting and thermally stable non-aggregating benzannulated quinolines and acridines were designed and prepared from ketene-S,S-acetal under mild conditions through C–C bond formation. Photophysical and electrochemical analyses of these bipolar N-heterocyclic compounds revealed intense solvatochromism due to the intramolecul...

Solar cell fabrication on flexible thin plastic sheets needs deposition of transparent conducting anode layers at low temperatures. ITO thin films are deposited on glass by RF sputtering at substrate temperature of 70°C and compare their phase, morphology, optical, and electrical properties with commercial ITO. The films contain smaller nanocrystal...

Aluminum-doped zinc oxide thin films have been deposited on glass substrates by R.F. sputtering using ZnO(98%)-Al2O3(2%) target in different sputtering gaseous environments, viz., Ar, Ar/O2 and Ar/N2+H2 at 80°C. These films have been studied with regard to phase, microstructure, optical absorption and sheet resistance for application in photovoltai...

Two well known electroluminescent (EL) compounds, aluminum and zinc metallo-8-hydroxyquinolates have been synthesized. Their chemical and physical properties like NMR, FTIR, Cyclic Voltammetry, absorption and EL are studied. Organic LEDs are fabricated using both the material as emissive layers. Electroluminescence spectra of the complexes are meas...

In this paper we present the factors affecting electroluminescent properties of Zinc complexes of oxazole & thiazole derivatives. Electroluminescent spectra of the Zinc (II) complex of bis-[2-(2'-hydroxyphenyl) benzoxazole], [Zn (HPBO)2]2 and 2-(1'-hydroxynaphthyl) benzothiazole [Zn (HNBT)2] show unusual broadening and shows structural and photophy...

A new series of thermally stable blue light-emitting nonplanar pyrenylarenes having an amine donor and a nitrile acceptor group was prepared from a ketene-S,S-acetal under conventional heating and/or microwave irradiation. The photophysical, electrochemical, and optical behavior of donor-acceptor pyrenylarenes are demonstrated. The performance of b...

Hybrid solar cells have attracted considerable attention in recent years due to their high thermal and chemical stability, light weight, high carrier mobility, and low cost. The active layer of cadmium selenide (CdSe) nanoparticles- poly(3-hexylthiophene) (P3HT) is optimized in terms of their mass ratio and microstructure by using absorption and sc...

Hybrid solar cells have attracted considerable attention in recent years due to their high thermal and chemical stability, light weight, high carrier mobility, and low cost. The active layer of cadmium selenide (CdSe) nanoparticles- poly(3-hexylthiophene) (P3HT) is optimized in terms of their mass ratio and microstructure by using absorption and sc...

The electronic properties of ITO/PEDOT-PSS/P3HT-PCBM/LiF/Al organic solar cell have been investigated using current-voltage and capacitance-voltage techniques. The electrical parameters like ideality factor n, series resistance Rs and barrier height ϕb, have been extracted using current-voltage and capacitance-voltage techniques. The photovoltaic p...

A novel series of thermally stable yellow light emitting fluoranthenes with an amine donor and a nitrile acceptor was prepared from a ketene-S,S-acetal under mild conditions without using an organometal catalyst. The organic light emitting device of yellow fluoranthene 10b exhibited substantially low turn-on voltage (2.6 V) and maximum brightness o...

The "green emission defect" (GED) produced by fluorenones has significantly retarded the commercial scope of fluorene-based B-OLEDs. In this paper, for the first time, it is demonstrated that the "green light" emitting fluorenones 7 can be converted to "blue light" emitting fluorenones 10 by appropriate positioning of donor-acceptor and chromophori...

A novel series of thermally stable blue light emitting quateraryls with a piperidine donor and a nitrile acceptor was prepared from a ketene- S, S-acetal under mild conditions without using an organometal catalyst. The performance of a blue quateraryl 6e was investigated by fabricating a multilayer OLED with a configuration of ITO/PEDOT:PSS (40 nm)...

The recombination probability and hence the maximum light intensity of OLEDs largely depends upon the controlled injection of charge carriers and their confinement. In single layer OLEDs, recombination of carriers is highly affected due to quenching effects at cathode. In multilayer OLEDs, effective use of blocking and emissive layers provides bett...

Polymer Light Emitting Diodes (PLEDs) and Organic Light Emitting Diodes (OLEDs) have made great progress in terms of efficiency, brightness and lifetimes during its last few years of development. The technology looks mature enough to produce real commercial products like high-resolution flat panel displays for cell phones, computers and televisions...

The improvement in reverse recovery of power NPN bipolar transistor (BJT) through incorporation of “universal contact” in the base is studied in detail. It is shown that use of universal contact allows redistribution of base current in saturation from collector region where recombination lifetime is high to extrinsic base region where effective rec...

We report on the spectroscopic ellipsometry (SE) characterization and modeling of the light and environmental induced degradation of Poly(p-phenylenevinylene) (PPV) prepared by xanthate precursor route. We find a decrease in the refractive index as well as absorption coefficients after exposure to light in air ambient. Further, a decrease in film d...

The use of p+n+ universal contact for improving switching performance in diodes is studied in detail. A theoretical framework is described which shows that the incorporation of universal contact either at the end of the lightly doped region or in the injecting p or n regions of the diode can all be viewed as an attempt to reduce the effective minor...