http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Room temperature chemical synthesis of Cu(OH)<sub>2</sub> thin films for supercapacitor application
Gurav, K.V.,Patil, U.M.,Shin, S.W.,Agawane, G.L.,Suryawanshi, M.P.,Pawar, S.M.,Patil, P.S.,Lokhande, C.D.,Kim, J.H. Elsevier Sequoia 2013 Journal of alloys and compounds Vol.573 No.-
Room temperature soft chemical synthesis route is used to grow nanograined copper hydroxide [Cu(OH)<SUB>2</SUB>] thin films on glass and stainless steel substrates. The structural, morphological, optical and wettability properties of Cu(OH)<SUB>2</SUB> thin films are studied by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), UV-vis spectrophotometer and water contact angle measurement techniques. The results showed that, room temperature chemical synthesis route allows to form the nanograined and hydrophilic Cu(OH)<SUB>2</SUB> thin films with optical band gap energy of 3.0eV. The electrochemical properties of Cu(OH)<SUB>2</SUB> thin films are studied in an aqueous 1M NaOH electrolyte using cyclic voltammetry. The sample exhibited supercapacitive behavior with 120F/g specific capacitance.
Evolution of Detrimental Secondary Phases in Unstable Cu2ZnSnS4 Films during Annealing
Hyo Rim Jung,신승욱,K.V. Gurav,Myeng-Gil Gang,Jeong Yong Lee,문종하,김진혁 대한금속·재료학회 2016 ELECTRONIC MATERIALS LETTERS Vol.12 No.1
The formation and phase evolution of Cu-S based compounds in kesteriteCu2ZnSnS4 (CZTS) absorbing thin films is a critical factor affecting theperformance of these materials in thin film solar cells (TFSCs). However,to the best of our knowledge, few studies have investigated the segregationof Cu-S based compounds in kesterite thin films during the sulfurizationprocess. In this study, stacked Cu/SnS2/ZnS precursor thin films wereannealed to systematically study the segregation and phase evolution ofCu-S based compounds in kesterite thin films subjected to functionalsulfurization times at 550°C. The stacked precursor thin films appeared tobe fully transformed to the pure kesterite phase when the sulfurizationtimes are over 30 min. when analyzed using X-ray diffraction and Ramanspectroscopy. However, transmission electron microscopy (TEM)characterization revealed that Cu-S based compounds segregated in thekesterite CZTS thin films annealed for 120 min. at 550°C. Based on theexperimental results obtained for functional sulfurization times, amechanism for Cu-S based compounds segregation and the phaseevolution process is proposed.
Lokhande, A.C.,Gurav, K.V.,Jo, E.,He, M.,Lokhande, C.D.,Kim, J.H. Elsevier Science Publishers 2016 Optical materials Vol.54 No.-
Copper tin sulfide (CTS) is an emerging candidate for solar application due to its favorable band gap and higher optical absorption coefficient. Kuramite-Tetragonal Cu<SUB>3</SUB>SnS<SUB>4</SUB> (CTS) monodisperse nanoparticles are prepared by hot injection technique involving cost effective sulfate metal precursor source. A protocol for controlled crystal structure has been demonstrated by variation of cationic Cu:Sn ratio. The crystal structure, size, phase purity, atomic composition, oxidation state and optical properties of the nanoparticles are confirmed from X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman, energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS) and UV-visible spectroscopy, respectively. Hexagonal shaped particles within the size distribution of 7-9nm with an optimal band gap of 1.28eV are obtained. XPS study shows the Cu<SUP>1+</SUP>, Sn<SUP>4+</SUP> and S<SUP>2-</SUP> oxidation states. The effects of influential factors such as metal precursor ratio, metal precursor source, reaction time, heating rate and solvents have been demonstrated systematically on the synthesis of CTS nanoparticles. The plausible mechanism of the formation of CTS nanoparticles has been proposed. The obtained results provide new insight for applying CTS nanoparticles in photovoltaic applications.
Effect of bath temperature on the properties of nanocrystalline ZnO thin films.
Pawar, S M,Gurav, K V,Shin, S W,Choi, D S,Kim, I K,Lokhande, C D,Rhee, J I,Kim, J H American Scientific Publishers 2010 Journal of Nanoscience and Nanotechnology Vol.10 No.5
<P>The nanocrystalline zinc oxide (ZnO) thin films have been prepared by chemical bath deposition (CBD) method from aqueous zinc nitrate solution at room temperature (25 degrees C) and at higher temperature (75 degrees C). The changes in structural, morphological and optical properties were studied by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), and optical absorption. The structural studies revealed that the film deposited at room temperature showed mixed phases of ZnO and Zn(OH)2 with wurtzite and orthorhombic crystal structure whereas at higher temperature, the deposited film is ZnO with wurtzite crystal structure. After air annealing at 400 degrees C, all the films converted into pure ZnO with wurtzite crystal structure. The films deposited at room temperature showed fibrous surface morphology with interconnected flakes while films deposited at higher temperature shows well-developed nano-rod morphology. Optical study shows that band gap energy (E(g)) of as-deposited thin films deposited at room temperature and at higher temperature are 3.81 and 3.4 eV, decreases up to 3.20 eV, after annealing treatment.</P>
Chemical synthesis of Cu<sub>2</sub>SnS<sub>3</sub> (CTS) nanoparticles: A status review
Lokhande, A.C.,Gurav, K.V.,Jo, E.,Lokhande, C.D.,Kim, J.H. Elsevier Sequoia 2016 JOURNAL OF ALLOYS AND COMPOUNDS Vol.656 No.-
Solar industry has received great attention due to its potential capability for satisfying the increasing energy needs. Efforts are being made to develop high power conversion efficient solar cells. High efficiency solar cells based on CdTe and CuInGaS<SUB>2</SUB> (CIGS) quaternary chalcogenide compounds are costly and toxic. As a replacement for these costly and toxic compounds, earth abundant and nontoxic Cu<SUB>2</SUB>ZnSnS<SUB>4</SUB> (CZTS) compound was developed which showed promising application in solar cells. The commercialization of this compound is an issue as it is difficult to control the individual elemental composition and structure due to increased number of elements in the absorber compound. Hence, there is a great need to find the alternative material to address these issues. These compound semiconductors are replaced with environmental benign and low cost ternary Cu<SUB>2</SUB>SnS<SUB>3</SUB> (CTS) compound wherein the constituent elements such as copper, tin and sulfur are earth abundant and nontoxic. CTS is an emerging candidate for solar application because of its favorable band gap and higher optical absorption coefficient. Solar cells based on nanoparticle synthesized CTS have shown good power conversion efficiency (PCE 3.66%) due to size confinement effect. This review focuses on the recent developments in CTS nanoparticle synthesis by various chemical methods. A brief overview of these methods including its advantages along with its working mechanism is discussed. The effect of various experimental parameters of these chemical methods on CTS synthesis is elaborated. The structural, electrical and optical properties of CTS have been outlined and its potential applications have been presented. Finally, the challenges involved in the CTS synthesis and the scope for further development are discussed.
CdS surface encapsulated ZnO nanorods: Synthesis to solar cell application
Nikam, Pratibha R.,Baviskar, Prashant K.,Sali, Jaydeep V.,Gurav, Kishor V.,Kim, Jin H.,Sankapal, Babasaheb R. Elsevier 2016 Journal of Alloys and Compounds Vol.689 No.-
<P><B>Abstract</B></P> <P>Surface coating of CdS nanoparticles over the ZnO nanorods have been performed by using simple successive ionic layer adsorption and reaction at room temperature. Initially, the seed/compact ZnO layer have been deposited via SILAR (successive ionic layer adsorption and reaction) on to fluorine doped tin oxide coated glass (FTO) substrate followed by synthesis of ZnO nanorods by chemical bath deposition method. The synthesized nano heterostructure was characterized by X-ray diffraction (XRD), UV–Vis spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray analysis (EDX) and high resolution-transmission electron microscopy (HR-TEM) techniques. The photovoltaic performance of the cell was recorded with a conversion efficiency of 0.123% under 100 mW/cm<SUP>2</SUP> simulated sunlight at AM 1.5G conditions.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Synthesis of ZnO nanorods using simple solution chemistry. </LI> <LI> Surface encapsulation of ZnO nanorods with CdS nanoparticles using SILAR method. </LI> <LI> CdS sensitized ZnO nano heterojunction solar cell show 0.123% efficiency. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>The development of a heterostructure using one dimensional (1-D) confined nanomaterials of inorganic metal oxides and chalcogenides semiconductor. The heterostructure was constructed by using ZnO nanorods encapsulated with CdS nanoparticles without use of capping agent with precise control over the morphology and microstructure towards nano heterostructure solar cell application. The energy conversion efficiency (η) of 0.123% was obtained under standard illumination of simulated sun light.</P> <P>[DISPLAY OMISSION]</P>