Influence of Zn concentration and dye adsorption time on the photovoltaic performance of M-SILAR deposited ZnO-based dye sensitized solar cells

Gaikwad, M.A.,Suryawanshi, M.P.,Nikam, S.S.,Bhosale, C.H.,Kim, J.H.,Moholkar, A.V. Elsevier Sequoia 2016 Journal of photochemistry and photobiology Chemist Vol.329 No.-

<P>Zinc oxide (ZnO) thin films have been deposited with ultrasonic rinsing assisted modified successive ionic layer adsorption and reaction (M-SILAR) method. The effect of Zn concentration on the growth of ZnO films and power conversion efficiency (PCE) of dye-sensitized solar cells (DSSCs) have been studied. The surface morphology changes from nanorods to the nanoflowers like structure as a result of coalescence of the nanorods. Also, the significant effect of the dye adsorption time of photoelectrodes on the overall PCE of ZnO based DSSCs has been investigated systematically. It is found that the chemical stability is the foremost issue for ZnO photoelectrode. The prolonged dye adsorption time is responsible for the deterioration of the ZnO nanostructure due to the formation of Zn2+/N3 dye aggregates. The DSSC prepared using photoelectrode of 0.1 M Zn concentration and dye loading time of 18 h exhibited a highest PCE of 0.70%, since it possesses well-defined 1D nanostructure which facilitates very low reverse saturation current density and longer electron lifetime. (C) 2016 Elsevier B.V. All rights reserved.</P>

Photoelectrochemical performance of surfactant (polyvinyl alcohol) assisted PbS thin films grown by chemical route

Nikam, S. S.,Suryawanshi, M. P.,Gaikwad, M. A.,Kim, J. H.,Moholkar, A. V. Springer Science + Business Media 2017 Journal of materials science. Materials in electro Vol.28 No.7

<P>Polyvinyl alcohol is used as a surfactant in the chemical bath deposition of PbS thin films, which causes compact, pinhole free and uniform PbS thin films. Influence of deposition time on the structural, optical, morphological, compositional, electro-chemical and photo-electrochemical (PEC) properties of the PbS thin films are studied. The charge transfer resistance is analysed using electrochemical impedance spectroscopy. The best PEC device fabricated using optimized deposition time (3 h) showed short circuit current density (J(sc)) of 1.68 mA. After annealing the optimised P-63 sample at 75 A degrees C for 1.5 h the composition changed from Pb rich to near stoichiometric. For typical PA sample J(sc) improves to 2.13 mA and photo conversion efficiency advances from 0.045 to 0.072%.</P>

Electrocatalytic performance evaluation of cobalt hydroxide and cobalt oxide thin films for oxygen evolution reaction

Babar, P.T.,Lokhande, A.C.,Pawar, B.S.,Gang, M.G.,Jo, Eunjin,Go, Changsik,Suryawanshi, M.P.,Pawar, S.M.,Kim, Jin Hyeok Elsevier 2018 APPLIED SURFACE SCIENCE - Vol.427 No.1

<P><B>Abstract</B></P> <P>The development of an inexpensive, stable, and highly active electrocatalyst for oxygen evolution reaction (OER) is essential for the practical application of water splitting. Herein, we have synthesized an electrodeposited cobalt hydroxide on nickel foam and subsequently annealed in an air atmosphere at 400°C for 2h. In-depth characterization of all the films using X-ray diffraction (XRD), X-ray photoelectron emission spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM), electrochemical impedance spectroscopy (EIS) and linear sweep voltammetry (LSV) techniques, which reveals major changes for their structural, morphological, compositional and electrochemical properties, respectively. The cobalt hydroxide nanosheet film shows high catalytic activity with 290mV overpotential at 10mAcm<SUP>−2</SUP> and 91mVdec<SUP>−1</SUP> Tafel slope and robust stability (24h) for OER in 1M KOH electrolyte compared to cobalt oxide (340mV). The better OER activity of cobalt hydroxide in comparison to cobalt oxide originated from high active sites, enhanced surface, and charge transport capability.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Simple and highly efficient method for deposition of Cobalt based electrode. </LI> <LI> Efficient OER performance of Co(OH)<SUB>2</SUB>. </LI> <LI> Co(OH)<SUB>2</SUB> exhibits low overpotential (290mV) over Co<SUB>3</SUB>O<SUB>4</SUB> (340mV) at current density of 10mAcm<SUP>−2</SUP>. </LI> <LI> Superior performance of Co(OH)<SUB>2</SUB> mainly due to large surface and active sites compare to Co<SUB>3</SUB>O<SUB>4</SUB>. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Improved performance of sputtered Cu₂(Sn,Ge)S₃ thin film for photovoltaic application via controlled Ge doping

He, Mingrui,Kim, Jihun,Suryawanshi, M.P.,Ghorpade, U.V.,Gang, Myengil,Suryawanshi, U.P.,Kim, Jin Hyeok Elsevier 2018 Materials letters Vol.211 No.-

<P><B>Abstract</B></P> <P>Cu<SUB>2</SUB>SnS<SUB>3</SUB> (CTS) thin films have been investigated extensively as an absorber layer for photovoltaic applications owing to the use of low-cost and earth-abundant materials. However, the performance of CTS solar cells still suffers from voltage deficit, resulting in a low value of open-circuit voltage (<I>V</I> <SUB>oc</SUB>). In this study, we introduce a Ge layer into CTS materials using Ge metal target asa doping source. Subsequently, the sputtered Cu/Ge/Sn precursors are sulfurized under sulfur vapor ambient to form a Cu<SUB>2</SUB>(Sn,Ge)S<SUB>3</SUB> (CTGS) thin film. Meanwhile, we also fabricate a CTS solar cell under the same experimental conditions as compared with CTGS solar cell. The Ge layer of thickness approximately 20nm enhanced the efficiency from 0.45% (CTS) to 3.05% (CTGS), whereas the improvement in performance was limited for Ge layer of thickness more than 20nm.</P> <P><B>Highlights</B></P> <P> <UL> <LI> CTGS thin film solar cell exhibited the highest efficiency of 3.05%. </LI> <LI> The Ge layer of thickness approximately 20nm is optimized doping concentration for CTGS thin film solar cell. </LI> <LI> Ge doping approach can boost the value of <I>V</I> <SUB>oc</SUB> significantly. </LI> </UL> </P>

Fast response of sprayed vanadium pentoxide (V₂O₅) nanorods towards nitrogen dioxide (NO₂) gas detection

Mane, A.A.,Suryawanshi, M.P.,Kim, J.H.,Moholkar, A.V. Elsevier BV * North-Holland 2017 Applied Surface Science Vol.403 No.-

<P><B>Abstract</B></P> <P>The V<SUB>2</SUB>O<SUB>5</SUB> nanorods have been successfully spray deposited at optimized substrate temperature of 400°C onto the glass substrates using vanadium trichloride (VCl<SUB>3</SUB>) solution of different concentrations. The effect of solution concentration on the physicochemical and NO<SUB>2</SUB> gas sensing properties of sprayed V<SUB>2</SUB>O<SUB>5</SUB> nanorods is studied at different operating temperatures and gas concentrations. The XRD study reveals the formation of V<SUB>2</SUB>O<SUB>5</SUB> having an orthorhombic symmetry. The FE-SEM micrographs show the nanorods-like morphology of V<SUB>2</SUB>O<SUB>5</SUB>. The AFM micrographs exhibit a well covered granular surface topography. For direct allowed transition, the band gap energy values are found to be decreased from 2.45eV to 2.42eV. The nanorods deposited with 30mM solution concentration shows the maximum response of 24.2% for 100ppm NO<SUB>2</SUB> gas concentration at an operating temperature of 200°C with response and recovery times of 13s and 140s, respectively. Finally, the chemisorption mechanism of NO<SUB>2</SUB> gas on the V<SUB>2</SUB>O<SUB>5</SUB> nanorods is discussed.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Effect of solution concentration on physicochemical properties of sprayed V<SUB>2</SUB>O<SUB>5</SUB> nanorods is studied. </LI> <LI> Good re­sponse and short re­sponse- re­covery times of V<SUB>2</SUB>O<SUB>5</SUB> nanorods towards NO<SUB>2</SUB> gas show it is potential material for fab­ri­ca­tion of NO<SUB>2</SUB> sensor. </LI> <LI> The chemisorption mechanism of NO<SUB>2</SUB> gas on the V<SUB>2</SUB>O<SUB>5</SUB> nanorods is discussed. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

A chemical approach for synthesis of photoelectrochemically active Cu₂ZnSnS₄ (CZTS) thin films

Suryawanshi, M.P.,Shin, S.W.,Ghorpade, U.V.,Gurav, K.V.,Agawane, G.L.,Hong, C.W.,Yun, J.H.,Patil, P.S.,Kim, J.H.,Moholkar, A.V. Association for Applied Solar Energy ; Elsevier Sc 2014 SOLAR ENERGY -PHOENIX ARIZONA THEN NEW YORK- Vol.110 No.-

A cost-effective chemical approach is developed for the synthesis of photoelectrochemically active Cu<SUB>2</SUB>ZnSnS<SUB>4</SUB> (CZTS) thin films. More specifically, CZTS precursor thin films are prepared by the sequential deposition of Cu<SUB>2</SUB>SnS<SUB>3</SUB> and ZnS layers using a successive ionic adsorption and reaction (SILAR) technique. The CZTS precursor thin films are sulfurized at different temperatures ranging from 500 to 575<SUP>o</SUP>C at intervals of 25<SUP>o</SUP>C. The influence of different sulfurization temperatures on the structural, compositional, morphological, and optical properties, as well as on the photoelectrochemical performance is studied. The films sulfurized at 575<SUP>o</SUP>C showed a prominent kesterite phase with a nearly stoichiometric composition, dense microstructure with the desired thickness, and an optical band gap energy of 1.47eV. The photoelectrochemical (PEC) cell fabricated using CZTS thin film sulfurized at 575<SUP>o</SUP>C showed the highest short circuit current density (J<SUB>sc</SUB>) of 8.27mA/cm<SUP>2</SUP> with a power conversion efficiency (η) of 1.06%.

A review on pulsed laser deposited CZTS thin films for solar cell applications

Vanalakar, S.A.,Agawane, G.L.,Shin, S.W.,Suryawanshi, M.P.,Gurav, K.V.,Jeon, K.S.,Patil, P.S.,Jeong, C.W.,Kim, J.Y.,Kim, J.H. Elsevier 2015 JOURNAL OF ALLOYS AND COMPOUNDS Vol.619 No.-

<P><B>Abstract</B></P> <P>Cu<SUB>2</SUB>ZnSnS<SUB>4</SUB>; commonly abbreviated as CZTS is a promising material for low cost thin film solar cells, because of its suitable band gap energy of around 1.5eV and large absorption coefficient of over 10<SUP>4</SUP> cm<SUP>−1</SUP>. All the constituents of this material are abundant in the earth’s crust, and they are not toxic making it a smarter choice. Since 1996, after the initial success of the CZTS based solar cell (with its light to electrical conversion efficiency of 0.6%), significant progress in this research area has been achieved, especially in the last five years. Now-a-days, the conversion efficiency of the CZTS thin film solar cell has improved to 12%. Over 600 papers on CZTS have been published since 2001, and the majority of these discuss the preparation of CZTS thin films by different methods. So far, many physical and chemical techniques have been employed for preparing CZTS thin films. Among them, the pulsed laser deposition (PLD) is a versatile deposition method. PLD is a simple, but multipurpose, experimental method that finds use as a means of modeling a very diverse range of materials, and in extensive areas of thin film deposition and multi-layer research. This technique is suitable for depositing high quality films with complex compositions because of its influencing properties such as harmonious transfer of species from the target to substrate, enrichment in crystallinity, clean deposition, and simplicity and flexibility in the engineering design. On the occasion of the 25th anniversary of PLD, this manuscript, reviews the synthesis of CZTS semiconductor thin films fabricated by PLD. This review begins with a description of the PLD system, and then introduces the CZTS and preparation of the CZTS target for PLD deposition. A survey of pulsed laser deposited CZTS thin films and their solar cell performance is discussed in detail. Finally, we present perspectives for further developments of PLD for a CZTS based solar cell absorber layer.</P>

Superior selectivity and enhanced response characteristics of palladium sensitized vanadium pentoxide nanorods for detection of nitrogen dioxide gas

Mane, A.A.,Suryawanshi, M.P.,Kim, J.H.,Moholkar, A.V. Academic Press 2017 Journal of Colloid and Interface Science Vol. No.

<P><B>Abstract</B></P> <P>Vanadium pentoxide (V<SUB>2</SUB>O<SUB>5</SUB>) nanorods have been deposited onto the glass substrates by spraying 75ml of 30mM vanadium trichloride (VCl<SUB>3</SUB>) solution at optimized substrate temperature of 400°C. The XRD study confirms the formation of orthorhombic crystal structure of V<SUB>2</SUB>O<SUB>5</SUB> nanorods. The FE-SEM micrograph shows the nanorods-like morphology of V<SUB>2</SUB>O<SUB>5</SUB>. The presence of palladium (Pd) in the Pd-sensitized V<SUB>2</SUB>O<SUB>5</SUB> nanorods is confirmed using EDAX study. The gas sensing measurements show that the Pd-sensitized V<SUB>2</SUB>O<SUB>5</SUB> sensing material is an outstanding candidate for nitrogen dioxide (NO<SUB>2</SUB>) gas detection. Obtained results demonstrate that the Pd-sensitized V<SUB>2</SUB>O<SUB>5</SUB> nanorods show the superior selectivity for NO<SUB>2</SUB> gas in comparison with other gases such as NH<SUB>3</SUB>, H<SUB>2</SUB>S, CO, CO<SUB>2</SUB> and SO<SUB>2</SUB> at an operating temperature of 200°C. It shows the 75% response for 100ppm NO<SUB>2</SUB> gas concentration with response and recovery times of 22s and 126s, respectively. Finally, the gas sensing mechanism based on chemisorption process is proposed to illustrate how Pd nanoparticles affect the gas sensing characteristics (response and response-recovery times).</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

CZTS based thin film solar cells: a status review

Suryawanshi, M.P.,Agawane, G.L.,Bhosale, S.M.,Shin, S.W.,Patil, P.S.,Kim, J.H.,Moholkar, A.V. Maney Publishing 2013 Materials technology Vol.28 No.1

Cu₂Sn_1- _xGe_xS₃ thin film solar cells fabricated from sputtered precursors: Effects of soft-annealing process

He, Mingrui,Kim, Jihun,Suryawanshi, M.P.,Ghorpade, U.V.,Gang, Myengil,Kim, Jin Hyeok Elsevier 2018 Materials science in semiconductor processing Vol.85 No.-

<P><B>Abstract</B></P> <P>Ge-doped Cu<SUB>2</SUB>SnS<SUB>3</SUB> (CTGS) thin films are promising photovoltaic materials for developing low-cost second-generation solar cells. The present work reported a soft-annealing process (annealing the as-deposited precursor without chalcogenide source) for fabricating CTGS solar cells, which is an efficient method to enhance the quality of CTGS thin films and show significant reforming on both as-deposited precursor and sulfurized film. The enlarged grain size and compact microstructure provide obvious evidence of improved efficiency. Further, the reduced defect density is attributed to using a 200 °C soft-annealed precursor. A clear increase in each performance parameter such as open-circuit voltage (<I>V</I> <SUB>oc</SUB>), short-circuit current density (<I>J</I> <SUB>sc</SUB>) and fill factor (<I>FF</I>) is observed as the soft-annealing temperature increased from 0 °C to 200 °C, whereas a limited enhancement was found at 300 °C. The CTGS solar cell prepared using the soft-annealing process showed an efficiency of 2.66%. In comparison, an efficiency of 1.93% has been achieved in cells fabricated without this process. The improved device performance indicates that further improvement in the CTGS solar cells could be achieved by adopting the soft-annealing precursor in an environmentally friendly manner.</P>