@article {44400, title = {Colloidal nanocomposite of TiN and N-doped few-layer graphene for plasmonics and electrocatalysis}, journal = {ACS Energy Letters}, volume = {2}, year = {2017}, month = {OCT}, pages = {2251-2256}, abstract = {

A combination of high carrier density, high surface area, solution processability, and low cost is desired in a material for electrocatalytic applications, including H-2 evolution and a counter electrode of a solar cell. Also, plasmonic-based applications in biological systems can be derived from such material. In this regard, a colloidal nanocomposite of TiN and N-doped few-layer graphene (TiN NFG) is synthesized from molecular precursors. TiN nano crystals (NCs) provide free electrons for electrical conductivity and plasmonics, whereas NFG is responsible for charge transport, high surface area, and colloidal stability. Colloidal TiN NFG nano composites exhibit a localized surface plasmon resonance band at around 700 nm. Coatings of the nanocomposite form a counter electrode for efficient (8.9\%) dye-sensitized solar cells. Furthermore, the nanocomposite acts as an efficient electrocatalyst for hydrogen evolution reaction, exhibiting an overpotential similar to 161 mV at a current density of 10 mA/cm(2).

}, doi = {10.1021/acsenergylett.7b00741}, author = {Shanker, G. Shiva and Markad, Ganesh B. and Jagadeeswararao, Metikoti and Bansode, Umesh and Nag, Angshuman} } @article {43522, title = {On-axis pulsed laser deposition of hybrid perovskite films for solar cell and broadband photo-sensor applications}, journal = {Journal of Applied Physics}, volume = {121}, year = {2017}, month = {APR}, pages = {Article Number: 133107}, abstract = {High quality hybrid perovskite films are grown by the pulsed laser deposition (PLD) process through target stoichiometry and gas ambient control in the commonly used on-axis geometry which is compatible with PLD of other materials such as metal oxides. The use of an off-stoichiometric target and a momentum softening gas mixture of argon and hydrogen (90\%:10\%) is shown to yield dense films in the on-axis geometry with excellent stoichiometry and optical quality. The band gap can be easily tuned from 1.6 to 2.3 eV with either mixed halide composite target or successive depositions of inter-diffusing MAPbBr(3) and MAPbI(3) layers. A photosensor based on PLD grown MAPbI(3) is shown to render impressive performance over the broad range of wavelengths from 375 to 800 nm at a voltage of 5V bias. A planar heterojunction solar cell based on the dry-processed on-axis PLD grown film exhibits a champion conversion efficiency of 10.9\%. A heterostructure comprising in situ pulsed laser deposited Cu2O (p-type) followed by the hybrid perovskite film shows a rectifying characteristic and photoresponse.}, doi = {10.1063/1.4979865}, author = {Bansode, Umesh and Ogale, Satishchandra B.} } @article {44166, title = {Synthetic manipulation of hybrid perovskite systems in search of new and enhanced functionalities}, journal = {ChemSusChem}, volume = {10}, year = {2017}, month = {OCT}, pages = {3722-3739}, type = {Article}, abstract = {Over the past few years the organic-inorganic hybrid perovskite systems have emerged as a promising class of materials for photovoltaic and electroluminescent thin-film device applications, in view of their unique set of tunable optoelectronic properties. Importantly, these materials can be easily solution-processed at low temperatures and as such are amenable to facile molecular engineering. Thus, a variety of low-dimensional forms and quantum structures of these materials can be obtained through strategic synthetic manipulations through small molecule incorporation or molecular ion doping. In this Minireview, we specifically focus on these approaches and outline the possibilities of utilizing these for enhanced functionalities and newer application domains.}, doi = {10.1002/cssc.201701093}, author = {Naphade, Rounak and Nagane, Satyawan and Bansode, Umesh and Tathavadekar, Mukta and Sadhanala, Aditya and Ogale, Satishchandra} } @article {46231, title = {Weak intermolecular interactions in covalent organic framework-carbon nanofiber based crystalline yet flexible devices}, journal = {ACS Applied Materials \& Interfaces}, volume = {11}, year = {2019}, month = {AUG}, type = {Article}, abstract = {

The redox-active and porous structural backbone of covalent organic frameworks (COFs) can facilitate high-performance electrochemical energy storage devices. However, the utilities of such 2D materials as supercapacitor electrodes in advanced self-charging power-pack systems have been obstructed due to the poor electrical conductivity and subsequent indigent performance. Herein, we report an effective strategy to enhance the electrical conductivity of COF thin sheets through the in situ solid-state inclusion of carbon nanofibers (CNF) into the COF precursor matrix. The obtained COF-CNF hybrids possess a significant intermolecular π{\textperiodcentered}{\textperiodcentered}{\textperiodcentered}π interaction between COF and the graphene layers of the CNF. As a result, these COF-CNF hybrids (DqTp-CNF and DqDaTp-CNF) exhibit good electrical conductivity (0.25 {\texttimes} 10{\textendash}3\ S cm{\textendash}1), as well as high performance in electrochemical energy storage (DqTp-CNF: 464 mF cm{\textendash}2\ at 0.25 mA cm{\textendash}2). Also, the fabricated, mechanically strong quasi-solid-state supercapacitor (DqDaTp-CNF SC) delivered an ultrahigh device capacitance of 167 mF cm{\textendash}2\ at 0.5 mA cm{\textendash}2. Furthermore, we integrated a monolithic photovoltaic self-charging power pack by assembling DqDaTp-CNF SC with a perovskite solar cell. The fabricated self-charging power pack delivered excellent performance in the areal capacitance (42 mF cm{\textendash}2) at 0.25 mA cm{\textendash}2\ after photocharging for 300 s.

}, doi = {10.1021/acsami.9b08625}, author = {Mohammed, Abdul Khayum and Vijayakumar, Vidyanand and Halder, Arjun and Ghosh, Meena and Addicoat, Matthew and Bansode, Umesh and Kurungot, Sreekumar and Banerjee, Rahul} }