Prashant K. Baviskar

Aligned 2D CuSCN nanosheets: a high performance field emitter

A low turn-on field of 2.4 V μm−1 is observed for the emission current density of 10 μA cm−2 from aligned copper thiocyanate (CuSCN) nanosheets. The observed low turn-on field is found to be superior to that of inorganic semiconducting and carbon based nanomaterials reported in the literature. The field emission current stability for the preset value of 1 μA over the period of 3 h is found to be better. Aligned CuSCN nanosheets were grown on fluorine doped tin oxide (FTO) coated glass substrates by a simple, low cost Successive Ion Layer Adsorption and Reaction (SILAR) technique at room temperature. Detail characterization of aligned CuSCN nanosheets has been carried out using Field Emission Scanning Electron Microscopy (FESEM), X-ray diffraction (XRD) and Transmission Electron Microscopy (TEM). To the best of our knowledge this is the first report on the field emission studies of aligned CuSCN nanosheets. The simple and inexpensive synthesis route coupled with superior field emission make the present emitter suitable for micro/nano electronic devices.

Synthesis of D–D–A-type small organic molecules with an enlarged linker system towards organic solar cells and the effect of co-adsorbents on cell performance

The synthesis of two D–D–A type novel small molecules bearing N,N-dimethyl/ethyl aniline as a donor and a methine unit connected with cyano and carboxyl groups as an acceptor linked with conjugated π-linkers has been performed. The obtained compounds were characterized by using FT-IR, 1H-NMR, 13C-NMR, LC-HR-MS, TGA, FE-SEM and UV-Vis spectroscopic techniques. These designed small organic molecules have been utilized for the fabrication of novel organic solar cells on high surface area titanium dioxide films consisting of interconnected nanoparticles with the device configuration FTO/TiO2/organic compound/electrolyte/platinum. The effect of cholic acid and dodecylamine as co-adsorbents with an organic compound has been studied towards the device performances and the results are incorporated herein.

The first report on SILAR deposited nanostructured uranyl sulphide thin films and their chemical conversion to silver sulphide

This paper reports the novel synthesis of uranyl sulphide (UO2S) thin films using the successive ionic layer adsorption and reaction (SILAR) technique at room temperature. Cationic exchange reaction was used to convert uranyl sulphide (UO2S) to silver sulphide (Ag2S). The influence of concentration variation on the structural and optical properties of UO2S and Ag2S thin films was investigated. The structural, surface morphological, elemental analysis and optical absorption studies were performed. Structural studies revealed that all the deposited films were nano-sized and amorphous in nature. Surface morphology showed that all the grains were spherical and granular in nature and grains got conglomerated to form a large particle. Also, the variations of the optical band gap and the width of the tail of localized states were represented as a function of various parameters.

SILAR controlled CdSe nanoparticles sensitized ZnO nanorods photoanode for solar cell application: Electrolyte effect

Controlled growth of different sizes of cadmium selenide (CdSe) nanoparticles over well aligned ZnO nanorods have been performed using successive ionic layer adsorption and reaction (SILAR) technique at room temperature (27 °C) in order to form nano heterostructure solar cells. Deposition of compact layer of zinc oxide (ZnO) by SILAR technique on fluorine doped tin oxide (FTO) coated glass substrate followed by growth of vertically aligned ZnO nanorods array using chemical bath deposition (CBD) at low temperature (<100 °C). Different characterization techniques viz. X-ray diffractometer, UV-Vis spectrophotometer, field emission scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy have been used to know the structural, optical, morphological and compositional properties of synthesized nano heterostructure. The photovoltaic performance of the cells with variation in SILAR cycles for CdSe and with use of different electrolytes have been recorded as J-V characteristics and the maximum conversion efficiency of 0.63% have been attained with ferro/ferri cyanide electrolyte for 12 cycles CdSe coating over 1-D ZnO nanorods.

Fabrication of titanium dioxide (TiO2) and mercury sulfide (HgS) heterojunction for photoelectrochemical study

This work reports a chemical solution sensitization of HgS nanocrystals on mesoporous TiO2 films for different deposition times. The adsorption of the precursor ions and the surface growth of the crystal were found to be affected during the temporal deposition of the HgS over spin-coated TiO2 films. The synthesized electrodes were characterized by structural, morphological, wettability, optical, photovoltaic, and electrochemical performances. The results designate the qualitative confirmation of the TiO2/HgS heterojunction formation, and the combination is explored for the photovoltaic application, which is first of its kind.

Correction to: Fabrication of titanium dioxide (TiO2) and mercury sulfide (HgS) heterojunction for photoelectrochemical study

In the original version of this article, the name of the following author name was not correct.

2D Porous ZnO Nanosheets: One Pot Synthesis with Low Turn-on Field

Low turn-on field of 2.3 V/µm was found for the emission current density of 10 µA/cm2 from 2D porous ZnO nanosheets. High current density of 0.76 mA/cm2 was drawn at an applied field of 4.1 V/µm. The observed low turn-on field of porous ZnO nanosheets has been found to be superior to the other ZnO nanostructures reported in the literature. Also, the emission current stability over a period of 3 hr is found to be better. The field emission current density-applied field (J-E) and current-time (I-t) measurements were carried out in all metal field emission microscope by using ‘close proximity’ (also termed as ‘planar diode’). The porous ZnO nanosheets were synthesized by Chemical Bath Deposition (CBD) method at room temperature followed by annealing at 200 oC. The annealed ZnO nanosheets were subjected to structural and morphological analysis prior to the field emission studies. The XRD spectrum of the as-synthesized product reveals formation of crystalline hexagonal phase of ZnO. Simple synthesis route with superior field emission properties indicate the possible use of porous ZnO nanosheets for micro/nanoelectronic devices.

Facile synthesis of D–π–A structured dyes and their applications towards the cost effective fabrication of solar cells as well as sensing of hazardous Hg(II)

We design and establish an environmentally benign synthesis of new D–π–A dyes containing imidazole derivatives structured to triphenylamine (TPA) as a donor and cyano acrylic groups acting as acceptors without using any toxic catalysts. These newly synthesized imidazole derivatives are anchored on TiO2, towards a cost effective dye sensitized organic solar cell, and achieve 0.22% solar-light to electricity conversion efficiency under standard AM 1.5G irradiation (100 mW cm−2). The most widely significant findings of this study are high thermal stability, smooth surface, strong intramolecular interaction between dyes and TiO2 which improve the performance of the dye sensitized solar cell. The metal ion sensing properties of both the dyes were investigated optically using UV-Vis absorption spectroscopy. The results exhibited high selectivity and sensitivity towards toxic Hg(II) ions compared to other tested metal ions. The binding constants (Ka) of receptors 1 and 2 are 2.53 × 105 M−1 and 0.99 × 105 M−1, respectively, which are reported with the help of Benesi–Hildebrand method.