@article {43943, title = {High-Performance Sensing Behavior Using Electronic Ink of 2D SnSe2 Nanosheets.}, journal = {Chemistry Select}, volume = {2}, year = {2017}, month = {MAY}, chapter = {4068-4075}, abstract = {

Most of the recent research work on layered chalcogenides is understandably focused on single atomic layers. However, it is uncertain if the single layer units are most ideal structures for enhanced gas-solid interactions. To probe this concern, we have synthesized few layer thick SnSe2\ nanosheets ink using liquid exfoliation method. The morphology, thickness / layering and elemental analysis of the sheets were characterized by using SEM, TEM, AFM, Raman spectroscopy and by XPS. The two dimensional (2D) SnSe2\ nanosheets sensor device with different thicknesses was assessed for the humidity and gas sensing performances with exposure to humidity in different conditions. The results show that compared to the bulk / thicker counterpart, sensor device of few SnSe2\ layers exhibit excellent sensitivity, recovery and ability to be tune the sensing performance with thickness and can be used in lab on chip devices.

}, doi = {10.1002/slct.201700261}, author = {Pawar, Mahendra and Kadam, Sunil and Late, Dattatray J.} } @article {48396, title = {Dual-functional 3-acetyl-2,5-dimethylthiophene additive-assisted crystallization control and trap state passivation for high- performance perovskite solar cells}, journal = {ACS Applied Energy Materials}, volume = {5}, year = {2022}, month = {DEC }, pages = {14701-14711}, type = {Article}, abstract = {

Defect-mediated charge recombination and successive degradation mainly lag the performance of perovskite solar cells (PSCs). Insufficiency or evaporation of organic cations leaves behind the undercoordinated Pb2+ ions, which act as severe charge recombination centers. Herein, theoretical and experimental insights into crystallization control and defect passivation of MAPbI3 perovskite by the dual-functional 3-acetyl-2,5-dimethylthiophene (ADT) molecule are pre-sented. Density functional theory calculations show that both functional groups of ADT possessing different interaction energies could interact with PbI2. The carbonyl group in ADT shows the dominant interaction with Pb2+ forming an intermediate product that might decrease the crystallization rate. Further, the coordinate bonding between ADT and uncoordinated Pb2+ ions in perovskite leads to defect passivation. The 0.6\% ADT-modified PSCs possess an average power conversion efficiency (PCE) of 18.22 +/- 0.80\% and the highest PCE of 19.03\%, whereas the pristine PSCs exhibit an average PCE of 16.23 +/- 1.32\% and the highest PCE of 17.47\%. Furthermore, the modified PSCs maintain 80\% of the initial PCE up to 650 h during storage at ambient conditions (RH = 35 +/- 5\%). The present study shows that the simultaneous crystalization control and defect passivation achieved via an ADT additive engineering approach could be an efficient strategy to enhance the PCE and stability of PSCs.

}, keywords = {3-acetyl-2, 5-dimethylthiophene, additive engineering, crystallization control, defect passivation, Perovskite solar cells}, issn = {2574-0962}, doi = {10.1021/acsaem.2c01881}, author = {Saykar, Nilesh G. and Iqbal, Muzahir and Pawar, Mahendra and Chavan, Kashinath T. and Mahapatra, Santosh K.} } @article {48342, title = {Titanium trisulfide nanosheets and nanoribbons for field emission- based nanodevices}, journal = {ACS Applied Nano Materials}, volume = {6}, year = {2023}, month = {JAN}, pages = {44-49}, type = {Article}, abstract = {

The field emission (FE) properties of TiS3 nanosheets and nanoribbons, synthesized by direct sulfuration of bulk titanium, are investigated. The nanosheets show an enhanced FE behavior with a low turn-on field of similar to 0.3 V/ mu m, required for drawing an emission current density of similar to 10 mu A/cm2. Interestingly, the TiS3 nanosheet emitter delivered a large emission current density of similar to 0.9 mA/ cm2 at a relatively low applied electric field of similar to 0.4 V/mu m. We have estimated the values of the field enhancement factor (beta), which are found to be similar to 5 x 104 for the TiS3 nanosheet emitter and similar to 4 x 103 for the nanoribbon emitter. We attribute the superior FE performance to the presence of atomically sharp edges and the reduced thickness of TiS3, as reflected in the high value of beta. In fact, the nanosheet sample presents a higher density of ultrathin layers (similar to 12 nm-thick), and thus, they have a larger edge to volume ratio than the nanoribbon samples (which are similar to 19 nm-thick). The superior FE behavior of TiS3 nanosheets over nanoribbons makes them a propitious field emitter and can be utilized for various FE-based applications, demanding large emission currents and lower operational voltages. Moreover, the FE current stability recorded on these samples confirms their promising performance. Thus, the present investigation brings out a great promise of TiS3 nanosheets and nanoribbons as field emitters for vacuum nanoelectronics devices.

}, keywords = {Current stability, field emission, nanoribbon, nanosheets, TiS3}, doi = {10.1021/acsanm.2c03460}, author = {Pawbake, Amit S. and Khare, Ruchita T. and Island, Joshua O. and Flores, Eduardo and Ares, Jose R. and Sanchez, Carlos and Ferrer, Isabel J. and Pawar, Mahendra and Frank, Otakar and More, Mahendra A. and van der Zant, Herre S. J. and Castellanos-Gomez, Andres and Late, Dattatray J.} }