03244nas 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-injection02586nas a2200325 4500008004100000022001400041245011200055210006900167260000800236300001200244490000800256520159300264653002001857653001301877653001801890653000801908653000801916100001601924700002001940700001801960700002101978700002401999700001902023700001902042700001702061700002002078700001802098700002002116856012402136 2019 eng d a1862-630000aSolvothermal growth of PbBi2Se4 nano-flowers: a material for humidity sensor and photodetector applications0 aSolvothermal growth of PbBi2Se4 nanoflowers a material for humid cJUN a19000650 v2163 a

In the present work, lead bismuth selenide (PbBi2Se4) nano-flowers are synthesized by using a simple solvothermal method. Humidity sensor and photodetector based on PbBi2Se4 nano-flowers are fabricated on indium tin oxide (ITO) substrates and their sensing properties are investigated. Formation of PbBi2Se4 is confirmed by XRD, EDS, and XPS whereas formation of nano-flowers is confirmed by SEM and TEM analysis. XRD analysis reveals the hexagonal crystal structure of PbBi2Se4 phase with a = b = 4.22 angstrom, and c= 17.42 angstrom. The surface morphology of PbBi2Se4 clearly shows the formation of well-organized flower-like nanostructures which closely resembles the shape of Dahlia. The elemental mapping of chemical constituents obtained from SEM-EDS analysis shows uniform distribution of chemical constituents for the Pb, Bi, and Se in PbBi2Se4 nano-flowers. The PbBi2Se4 nano-flowers based humidity sensor has a typical response time of approximate to 65s and recovery time of approximate to 75 s. In case of PbBi2Se4 nano-flowers-based photodetector, the response and recovery time are observed approximate to 121 and approximate to 123 s, respectively, under visible light illumination with photoresponsivity (5 x 10(-6)), photosensitivity (2.16%), and quantum efficiency (1.5 x 10(4)). The obtained results demonstrate the potential applications of solvothermally grown PbBi2Se4 nano-flowers-based devices for humidity sensors and photodetectors. The ease of the present work is to develop novel material to obtain device quality humidity sensors and photodetectors.

10ahumidity sensor10aPbBi2Se410aphotodetector10aXPS10aXRD1 aAher, Rahul1 aBhorde, Ajinkya1 aNair, Shruthi1 aBorate, Haribhau1 aPandharkar, Subhash1 aNaik, Dhirsing1 aVairale, Priti1 aKarpe, Smita1 aLate, Dattatray1 aPrasad, Mohit1 aJadkar, Sandesh uhttps://library.ncl.res.in/content/solvothermal-growth-pbbi2se4-nano-flowers-material-humidity-sensor-and-photodetector