01701nas a2200229 4500008004100000245012700041210006900168260000800237300001200245490000800257520089500265100001801160700002101178700002001199700002101219700002001240700001801260700002401278700001801302700002001320856013101340 2016 eng d00aWide band gap and conducting tungsten carbide(WC) thin films prepared by hot wire chemical vapor deposition(HW-CVD) method0 aWide band gap and conducting tungsten carbideWC thin films prepa cNOV a315-3170 v1833 a

In this letter, we report synthesis of tungsten carbide (WC) thin films having wide band gap(3.22-3.3 eV) with high electrical conductivity (80-1260 S/cm) by HW-CVD using heated using heated W filament and Tetra-fluoro-methane (CF4) gas. Formation of WC was confirmed by low angle XRD, Raman spectroscopy and x-ray photoelectron spectroscopy. UV-Visible spectroscopy analysis revealed that the synthesized films have high transmission at wavelength 500 nm. Electrical properties measured using Hall measurement show that these films are semiconductor. The obtained results imply that the growth of WC thin films is mainly from the atomic species(W and C) evaporated from the hot filament. The HW-CVD opens a novel route to synthesize wide band gap and conducting WC at a cost-efficient way for DSSCs and hydrogen evolution reaction (HER). (C) 2016 Elsevier B. V. All rights reserved.

1 aPawbake, Amit1 aWaykar, Ravindra1 aJadhavar, Ashok1 aKulkarni, Rupali1 aWaman, Vaishali1 aDate, Abhijit1 aLate, Dattatray, J.1 aPathan, Habib1 aJadkar, Sandesh uhttps://library.ncl.res.in/content/wide-band-gap-and-conducting-tungsten-carbidewc-thin-films-prepared-hot-wire-chemical-vapor01985nas a2200229 4500008004100000245010700041210006900148260000800217300002800225490000800253520119900261100001901460700001801479700002101497700002001518700001801538700002001556700001801576700001901594700002001613856012201633 2017 eng d00aSynthesis of gamma-WO3 thin films by hot wire-CVD and investigation of its humidity sensing properties0 aSynthesis of gammaWO3 thin films by hot wireCVD and investigatio cMAY aArticle Number: 16007170 v2143 aIn this study, monoclinic tungsten oxide (gamma-WO3) have been grown in a single step using HW-CVD method by resistively heating W filaments in a constant O-2 pressure. The formation of gamma-WO3 was confirmed using low angle-XRD and Raman spectroscopy analysis. Low angle-XRD analysis revealed that as-deposited WO3 film are highly crystalline and the crystallites have preferred orientation along the (002) direction. HRTEM analysis and SAED pattern also show the highly crystalline nature of WO3 with d spacing of similar to 0.38 nm, having an orientation along the (002) direction. Surface topography investigated by SEM analysis shows the formation of a uniform and homogeneous cauliflower like morphology throughout the substrate surface without flaws and cracks. A humidity sensing device incorporating WO3 is also fabricated, which shows a maximum humidity sensitivity factor of similar to 3954% along with a response time of similar to 14 s and a recovery time of similar to 25 s. The obtained results demonstrate that it is possible to synthesize WO3 in a single step by HW-CVD method and to fabricate a humidity sensor by using it. (C) 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim1 aJadkar, Vijaya1 aPawbake, Amit1 aWaykar, Ravindra1 aJadhavar, Ashok1 aDate, Abhijit1 aLate, Dattatray1 aPathan, Habib1 aGosavi, Suresh1 aJadkar, Sandesh uhttps://library.ncl.res.in/content/synthesis-gamma-wo3-thin-films-hot-wire-cvd-and-investigation-its-humidity-sensing03244nas a2200241 4500008004100000245011700041210006900158260000800227300001600235490000700251520241500258100002402673700002002697700002002717700001802737700001602755700001902771700002102790700001902811700002102830700001902851856013202870 2019 eng d00aProbing the effect of selenium substitution in kesterite-Cu2ZnSnS4 nanocrystals prepared by hot injection method0 aProbing the effect of selenium substitution in kesteriteCu2ZnSnS cAUG a14781-147900 v303 a

In this paper, we report the effect of sulfur (S) substitution with selenium (Se) in CZTS nanocrystals prepared by hot injection method. The formation of kesterite-copper zinc tin sulfide (Cu2ZnSnS4, CZTS) and copper zinc tin selenide (Cu2ZnSnSe4, CZTSe) nanocrystals is confirmed by X-ray diffraction (XRD), Raman spectroscopy and transmission electron microscopy (TEM) analysis. The XRD, TEM and atomic force microscopy (AFM) analysis shows an overall increase in average crystallite size upon Se substitution. AFM images revealed an increase in root mean square surface roughness (S-q) and average surface roughness (S-a) when S in CZTS is replaced by Se. The substitution of S by Se in host CZTS narrows the optical band gap from 1.56 to 1.03 eV. The ultraviolet photoelectron spectroscopy (UPS) analysis shows shift in valence band and conduction band edge in CZTSe compared to CZTS. The photocurrent density measurement in synthesized CZTSe thin films is similar to 4 to 5 times higher than CZTS thin films. The obtained results show that CZTSe can be a promising candidate as absorber material in photovoltaic applications.

1 aPandharkar, Subhash1 aRondiya, Sachin1 aBhorde, Ajinkya1 aNair, Shruthi1 aAher, Rahul1 aVairale, Priti1 aWaghmare, Ashish1 aNaik, Dhirsing1 aWaykar, Ravindra1 aJadhav, Yogesh uhttps://library.ncl.res.in/content/probing-effect-selenium-substitution-kesterite-cu2znsns4-nanocrystals-prepared-hot-injection