@article { ISI:000342766500050, title = {High performance all-organic flexural piezo-FET and nanogenerator via nanoscale soft-interface strain modulation}, journal = {Physical Chemistry Chemical Physics}, volume = {16}, number = {41}, year = {2014}, month = {SEP}, pages = {22874-22881}, publisher = {ROYAL SOC CHEMISTRY}, address = {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}, abstract = {

Flexural strain fields are encountered in a wide variety of situations and invite novel device designs for their effective use in sensing, actuating, as well as energy harvesting (nanogenerator) applications. In this work we demonstrate an interesting all-organic device design comprising an electrospun P(VDF-TrFE) fiber-mat built directly on a conducting PANI film, which is also grown on a flexible PET substrate, for flexural piezo-FET and nanogenerator applications. Orders of magnitude stronger modulation of electrical transport in PANI film is realized in this device as compared to the case of a similar device but with a uniform spin-coated P(VDF-TrFE) film. We find that in the flexural mode of operation, the interaction between the laterally modulated nanoscale strain field distributions created by the fibers and the applied coherent strain field strongly influences the carrier transport in PANI. The transport modulation is suggested to occur due to strain-induced conformational changes in P(VDF-TrFE) leading to changes in carrier localization-delocalization. We further show that the fiber-mat based device system also works as an efficient nanogenerator capable of delivering power for low power applications.

}, issn = {1463-9076}, doi = {10.1039/c4cp02155j}, author = {Dhakras, Dipti and Gawli, Yogesh and Chhatre, Shraddha and Wadgaonkar, Prakash and Ogale, Satishchandra} } @article { ISI:000344978200061, title = {Hollow Co0.85Se nanowire array on carbon fiber paper for high rate pseudocapacitor}, journal = {ACS Applied Materials \& Interfaces}, volume = {6}, number = {21}, year = {2014}, month = {NOV}, pages = {18844-18852}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

A supercapacitor electrode is fabricated with Co0.85Se hollow nanowires (HNW) array, which is synthesized by wet chemical hydrothermal selenization of initially grown cobalt hydroxyl carbonate nanowires on conductive CFP. The dense self-organized morphology of Co0.85Se HNWs is revealed by scanning/transmission electron microscopy. The as-synthesized Co0.85Se HNWs possess high pseudocapacitive property with high capacitance retention and high durability. The areal capacitance value is seen to vary from 929.5 to 600 mF cm(-2) (60\% retention) as the current density is increased from 1 to 15 mA cm(-2), an increase of a factor of 15. Based on mass loading, this corresponds to a very high gravimetric capacitance of 674 (for 2 mA cm(-2) or 1.48 Ag-1) and 444 Fg(1-) (for 15 mA cm(-2) or 11 A g(-1)) in a full-cell configuration with the Co0.85Se HNWs as cathode and activated carbon as anode (asymmetric configuration) promising results are obtained.

}, keywords = {asymmetric supercapacitor, carbon fiber paper, cobalt selenide, hydrothermal, pseudocapacitor, selenization}, issn = {1944-8244}, doi = {10.1021/am504333z}, author = {Banerjee, Abhik and Bhatnagar, Sumit and Upadhyay, Kush Kumar and Yadav, Prasad and Ogale, Satishchandra} } @article { ISI:000353930700023, title = {Hybrid perovskite films by a new variant of pulsed excimer laser deposition: a room-temperature dry process}, journal = {Journal of Physical Chemistry C}, volume = {119}, number = {17}, year = {2015}, month = {APR}, pages = {9177-9185}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

A new variant of the classic pulsed laser deposition (PLD) process is introduced as a room-temperature dry process for the growth and stoichiometry control of hybrid perovskite films through the use of nonstoichiometric single target ablation and off-axis growth. Mixed halide hybrid perovskite films nominally represented by CH(3)NH(3)PbI(3-x)A(x) (A = Cl or F) are also grown and are shown to reveal interesting trends in the optical properties and photoresponse. Growth of good quality lead-free CH3NH3SnI3 films is also demonstrated, and the corresponding optical properties are presented. Finally, perovskite solar cells fabricated at room temperature (which makes the process adaptable to flexible substrates) are shown to yield a conversion efficiency of about 7.7\%.

}, issn = {1932-7447}, doi = {10.1021/acs.jpcc.5b02561}, author = {Bansode, Umesh P. and Naphade, Rounak and Game, Onkar S. and Agarkar, Shruti A. and Ogale, Satishchandra} } @article { ISI:000380052000012, title = {Highly stable laser-scribed flexible planar microsupercapacitor using mushroom derived carbon electrodes}, journal = {Advanced Materials Interfaces}, volume = {3}, number = {11}, year = {2016}, month = {JUN}, pages = {1600057}, publisher = {WILEY-BLACKWELL}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, abstract = {

A report is presented on the fabrication of all solid-state interdigitated flexible microsupercapacitor using ultrafast and highly scalable laser scribing technique, using highly mesoporous carbon synthesized from biomass (mushroom) with hydrothermal preprocessing. The specific protocol used for carbon synthesis renders some unique property features to the material (surface area of 2604 m(2) g(-1) with hierarchical pore size distribution) in the context of supercapacitor electrode application. A polyvinyl alcohol (PVA)-H2SO4 gel electrolyte is used for electrochemical measurements. The microsupercapacitor shows high cyclic stability up to 15000 cycles. Moreover it shows nearly 90\% stability after 1000 bending cycles at 60 degrees angle. It also retains its performance even under 120 degrees bending condition. This work represents a facile and fast technique for microscaled device fabrication that can be easily commercialized. Moreover, the mushroom-derived carbon used to make the electrodes holds great promise in context of the stability and flexibility of flexible supercapacitors.

}, issn = {2196-7350}, doi = {10.1002/admi.201600057}, author = {Yadav, Poonam and Basu, Aniruddha and Suryawanshi, Anil and Game, Onkar S. and Ogale, Satishchandra} } @article {43573, title = {High-performance organic-inorganic hybrid piezo-nanogenerator via interface enhancedpolarization effects for self-powered electronic systems}, journal = {Advanced Materials Interfaces}, volume = {3}, year = {2016}, month = {OCT}, pages = {Article Number: 1600492}, abstract = {An electrospun fi ber based wearable organic-inorganic hybrid piezonanogenerator compose of suitably engineered P(VDF-TrFE) and BaTiO3 nanostructures is reported. In the case of the device with an electrospun mat of piezoelectric beta-phase P(VDF-TrFE) and BaTiO3 nanoparticulates fi lled in the interfi ber open spaces, a power density of 16 mu W cm(-2) is realized at an applied impact of 0.02 MPa (which essentially corresponds to the thumb pressure). A similar device, with BaTiO 3 additionally embedded in the P(VDF-TrFE) fi bers during their formation, renders a signifi cantly higher peak power density of 28 mu W cm(-2) with instantaneous power density of approximate to 8.8 mu W cm(-2) at the same touch pressure. This performance is attributed to the high density of interfaces in such a device and the corresponding enhancement in the dielectric response. It is demonstrated that the power generated from such a hybrid device structure can be used for small scale applications such as charging a mobile phone.}, doi = {10.1002/admi.201600492}, author = {Dhakras, Dipti and Ogale, Satishchandra} } @article { ISI:000368563000102, title = {Hybrid perovskite quantum nanostructures synthesized by electrospray antisolvent-solvent extraction and intercalation}, journal = {ACS Applied Materials \& Interfaces}, volume = {8}, number = {1}, year = {2016}, month = {JAN}, pages = {854-861}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

Perovskites based on organometal lead halides have attracted great deal of scientific attention recently in the context of solar cells and optoelectronic devices due to their unique and tunable electronic and optical properties. Herein, we show that the use of electrospray technique in conjunction with the antisolventsolvent extraction leads to novel low-dimensional quantum structures (especially 2-D nanosheets) of CH3NH3PbI3- and CH3NH3PbBr3-based layered perovskites with unusual luminescence properties. We also show that the optical bandgaps and emission characteristics of these colloidal nanomaterials can be tuned over a broad range of visible spectral region by compositional tailoring of mixed-halide (I- and Br-based) perovskites.

}, keywords = {2D nanostructure systems, antisolvent-solvent extraction, bandgap tuning, electrospray, nanosheets, perovskite, quantum dots}, issn = {1944-8244}, doi = {10.1021/acsami.5b10208}, author = {Naphade, Rounak and Nagane, Satyawan and Shanker, G. Shiva and Fernandes, Rohan and Kothari, Dushyant and Zhou, Yuanyuan and Padture, Nitin P. and Ogale, Satishchandra} } @article {44493, title = {High and reversible lithium ion storage in self-exfoliated triazole-triformyl phloroglucinol-basedcovalent organic nanosheets}, journal = {Advanced Energy Materials}, volume = {8}, year = {2018}, month = {MAR}, pages = {Article Number: 1702170}, abstract = {Covalent organic framework (COF) can grow into self-exfoliated nanosheets. Their graphene/graphite resembling microtexture and nanostructure suits electrochemical applications. Here, covalent organic nanosheets (CON) with nanopores lined with triazole and phloroglucinol units, neither of which binds lithium strongly, and its potential as an anode in Li-ion battery are presented. Their fibrous texture enables facile amalgamation as a coin-cell anode, which exhibits exceptionally high specific capacity of approximate to 720 mA h g(-1) (@100 mA g(-1)). Its capacity is retained even after 1000 cycles. Increasing the current density from 100 mA g(-1) to 1 A g(-1) causes the specific capacity to drop only by 20\%, which is the lowest among all high-performing anodic COFs. The majority of the lithium insertion follows an ultrafast diffusion-controlled intercalation (diffusion coefficient, D-Li(+) = 5.48 x 10(-11) cm(2) s(-1)). The absence of strong Li-framework bonds in the density functional theory (DFT) optimized structure supports this reversible intercalation. The discrete monomer of the CON shows a specific capacity of only 140 mA h g(-1) @50 mA g(-1) and no sign of lithium intercalation reveals the crucial role played by the polymeric structure of the CON in this intercalation-assisted conductivity. The potentials mapped using DFT suggest a substantial electronic driving-force for the lithium intercalation. The findings underscore the potential of the designer CON as anode material for Li-ion batteries.}, doi = {10.1002/aenm.201702170}, author = {Haldar, Sattwick and Roy, Kingshuk and Nandi, Shyamapada and Chakraborty, Debanjan and Puthusseri, Dhanya and Gawli, Yogesh and Ogale, Satishchandra and Vaidhyanathan, Ramanathan} }