effect of copper content on structural, morphological

ES Mater. Manuf., 2020, 10, 22-28

2 2 | ES Mater. Manuf., 2020, 10, 22-28 © Engineered Science Publisher LLC 2020

Effect of Copper Content on Structural, Morphological,

Optical and Photoelectrochemical Properties of SILAR

Deposited Cu3SnS4 Thin Films Harshad D. Shelke,1 Abhishek C. Lokhande,2 Jin H. Kim3 and Chandrakant D. Lokhande4,*

Abstract

In this study, Cu3SnS4 (CTS) thin films were deposited by successive ionic layer adsorption and reaction (SILAR) method at

room temperature. X-ray diffraction, Raman spectroscopy, scanning electronic microscopy, Ultra-violent-visible-near infrared

absorbance spectroscopy and photoelectrochemical analyses were used to follow the evolution of the investigated properties.

The results outlined a tetragonal (I-42m) CTS phase and a secondary copper sulfide (Cu2-xS) and Cu4SnS4 phase, and their

ratio strongly depends on the copper concentration. No traces of secondary phases of tin sulfide is found while CTS was

obtained. It was found that the application of additional Cu concentration increases from 0.025 to 0.075M, enhances the grain

growth in size and induces significant improvement of CTS crystallinity and power conversion efficiency. The optical band

gap ranges between 1.90, 1.21 and 1.07eV depending on the copper concentration 0.025, 0.050 and 0.075 M, respectively. This

study shows promising results, as a developing photovoltaic applications, using SILAR CTS as absorber.

Keywords: Band gap; Cu3SnS4; Optical properties; Molarity; Nanocrystals.

Received: 8 August 2020; Accepted date: 8 November 2020.

Article type: Research article.

1. Introduction

Last few decades, the copper based multinary compound

semiconductor materials are used as absorber materials in

photovoltaic technology.[1] Cu2ZnSnS4 (CZTS) has been

regarded as the alternative absorber layer to Cu(In,Ga)Se2 due

to its earth abundance and eco-friendly ingredients, optimal

direct band gap of 1.45 eV and high absorption coefficient in

the visible range.[2] But compositional control and growth of

single phase CZTS films are quite difficult to be processed.

The control of composition and phase structure in Cu3SnS4

compound is more convenient due to its fewer elements

compared with CZTS.

In particular, copper-based CuxSnSy, including Cu2SnS3,

Cu3SnS4, Cu4SnS4, Cu2Sn3S7, Cu5Sn2S7, etc., is an ideal

candidate material for solar cell and photocatalysis

applications owing to its high photocatalytic activities towards

hydrogen evolution, high absorption coefficient (>104 cm-1) in

the visible spectral range and proper band gap order (0.93 to

1.35 eV).[3-6] Currently, Cu3SnS4 (CTS) based ternary

semiconductors have grown more interests as significant

ternary I-IV-VI group semiconductors with diminutive or mid

band gap. Eco-friendly, low cost and non-toxic nature of CTS

similar to that of CZTS material has fascinated immense

attention due to its wide-ranging applications in photovoltaic

devices. The renewable energy resources necessitate to use

new materials in optoelectronic applications. In recent period,

CTS has received rising consideration as a promising

photovoltaic material for scalable production of thin film solar

cells because of its non-toxic and earth abundant elements, and

a tunable direct band gap of 0.9 to 1.5eV.[7] As for the synthesis

methods of CTS compound, a few studies have been reported

on chemical methods such as chemical bath deposition

(CBD),[8] electrodeposition,[9] successive ionic layer

adsorption and reaction (SILAR),[10] ball milling,[11]

solvothermal,[12] etc.

Among these chemical methods, SILAR is a simple, less

expensive and less time consuming method for the deposition

of semiconductor thin films. In SILAR method, sufficient

reaction time favors the complete chemical reaction and hence

produces pure phase compounds without secondary phases. In

the present work, CTS thin films have been synthesized by the

SILAR method. There are only a few reports existing for the

deposition of CTS thin films using the SILAR method. The

ES Materials and Manufacturing DOI: https://dx.doi.org/10.30919/esmm5f922

1 Thin Film Physics Laboratory, Department of Physics, Shivaji

University,

Kolhapur-416 004 (M.S.), India. 2 Department of Physics, Khalifa University of Science and

Technology, P.O. Box-127788, Abu Dhabi, United Arab Emirates

(UAE) 3 Optoelectronic Convergence Research Centre, Department of

Materials Science and Engineering, Chonnam National University,

Gwangju 500-757, South Korea. 4,* Centre for Interdisciplinary Research, D. Y. Patil University,

Kolhapur-416 006 (M.S.), India.

Email: [email protected] (C. Lokhande)

ES Materials & Manufacturing Research article

© Engineered Science Publisher LLC 2020 ES Mater. Manuf., 2020, 10, 22-28 | 23

aim of this present work is showing the effects of the material

composition (such as copper content) on the structural,

morphological, optical and electrical properties of CTS thin

films.

2. Experimental

2.1 Synthesis of CTS material

CTS thin films were deposited on ultrasonically cleaned soda

lime glass (SLG) and fluorine doped tin oxide (FTO)

substrates by the SILAR method. The chemical approach was

applied to synthesize CTS thin films. The mixed solution of

copper chloride (CuCl2.2H2O), tin chloride (SnCl2.2H2O) and

triethanolamine (TEA) was used as the cationic precursor and

sodium sulfide (Na2S.xH2O) solution was used as an anionic

precursor. In the deposition process of CTS, triethanolamine

solution was used as a complexing agent to bind metal cations

in the solution. The CTS precursor solution contained copper

chloride (0.025-0.075 M), tin chloride (0.025 M) and sodium

sulfide (0.1 M).

In the SILAR method, the substrate was immersed into

separate cationic and anionic precursor solutions for the

adsorption and reaction, and then rinsed with double-distilled

water (DDW) after each immersion to remove the loosely

bound particles and to avoid the precipitation. By repeating the

cycle described above, the CTS thin film with the desired

thickness was obtained by adjusting the preparative

parameters. These films were annealed for 3 hours at 300 °C

in a vacuum to improve the crystallinity. The CTS films were

well adherent, uniform and blackish in color.

To study the effect of copper salt concentration on the

formation of CTS films, copper chloride in the solution varied

from 0.025 - 0.075 M in the steps of 0.025 M. These samples

were further used for structural, morphological, optical and

photoelectrochemical cell (PEC) properties. The samples were

denoted as ‘S1’ for copper 0.025 M, ‘S2’ for copper 0.050 M

and ‘S3’ for copper 0.075 M, respectively.

2.2 Materials characterization

After film layers had been developed, the structural,

morphological, optical and electrical properties were

characterized. The structural characterization of CTS

nanoparticles was carried out using X-ray diffraction (XRD)

by BRUKER AXS D8 Advanced model X-ray diffractometer

equipped with Cu radiation (Kα of λ= 1.54 Ǻ) operated at 40

kV. Raman spectra were recorded in the range of 150–500 cm-

1 by using a micro-Raman spectrometer (Via Reflex UV

Raman microscope, Renishaw, U.K. at KBSI Gwangju center)

using a He–Ne laser source. The morphological features of

CTS nanoparticles were analyzed by scanning electron

microscopy (SEM) JEOL JSM-6390. SEM technique was

used to observe the grain size, rough morphology, and

distribution of the particles on the surface of the system. The

UV–visible optical absorption and transmittance spectra of

CTS thin films had been carried out to explore their optical

properties. The optical analysis was carried out by a HITACHI UV4100 spectrometer in the wavelength ranging from 310 to

900 nm at room temperature. The current density-voltage (J-

V) characteristics of the PEC cell were observed using a

Princeton Applied Research Potentiostat (273A) with a CTS

electrode as the working electrode.

Fig. 1 XRD patterns of a) CTS thin films prepared at different

copper concentration: S1 = 0.025 M, S2 = 0.050M and S3 =

0.075M; b) XRD spectra of diffraction angles, 2θ, around 28º at

copper concentration: S1 = 0.025M, S2 = 0.050M and S3 =

0.075M and c) diffraction angles, 2θ, around 47º at copper con-

centration: S1 = 0.025M, S2 = 0.050M and S3 = 0.075M.

20 30 40 50 60 70 80

S3

S2

22

0

Inte

ns

ity

(A

. U

.)

2 (Degree)

S1: 0.025 M

S2: 0.050 M

S3: 0.075 M

JCPDS: 00-033-0501 - Cu4SnS

4

− Cu2-x

S

S1

(a)

13

2

11

2

20 25 30 35 40

S1: 0.025 M

S2: 0.050 M

S3: 0.075 M

S3

S2

(x) Cu2SnS3

(y) Cu3SnS4In

ten

sity

(A

. U

.)

2 (Degree)

(y)(x)

S1

(b)

45.0 45.5 46.0 46.5 47.0 47.5 48.0 48.5 49.0 49.5 50.0

S1: 0.025 M

S2: 0.050 M

S3: 0.075 M

(y)

S3

S2

Inte

nsi

ty (

A. U

.)

2 (Degree)

S1

(x)

(x) Cu2SnS3

(y) Cu3SnS4

(c)

Research article ES Materials & Manufacturing


3. Results and discussion

3.1 Structural studies

Fig. 1a confirms the XRD patterns of CTS films deposited

with different molar concentrations such as 0.025, 0.050 and

0.075 M as denoted by S1, S2 and S3, respectively. The XRD

pattern gives an idea that the deposited films possess

tetragonal (I-42m) structure with a polycrystalline nature

(JCPDS No. 00-033-0501) of Cu3SnS4 material. For the

sample S1 prepared with 0.025 M concentration, a small peak

located at the angle 28.69° emerges in the XRD patterns. At

0.050 M concentration, the strong peaks at 47.110 are assigned

to (-2010) plane regarding the triclinic phase (JCPDS 00-027-

0198) of Cu2SnS3 material in S2 sample. Further increase the

molar concentration to 0.075 M, the formation of a higher Cu

content compound (Cu3SnS4) was observed with a tetragonal

(I-42m) structure. This result is expectable due to the reaction

mechanism between Cu and S.

The strongly oriented peaks at 2θ = 28.90, 47.620 and

57.010 corresponded to the diffraction planes along the (112),

(220) and (132) direction respectively. As the intensity of these

planes is observed higher in sample S3 compared to others.

Furthermore, the diffraction pattern could also match other

CTS secondary phase such as Cu4SnS4 (JCPDS Card: 00-027-

0196). This is because of an excess of CuCl2 in the solution.

The main information that could be deduced from the XRD

patterns is the presence of copper sulfide (Cu2-xS) in a covelite

structure (JCPDS Card: 00-079-2321) and, especially the

absence of secondary materials such as other binary

compounds (CuS, SnS2 and SnS). Further, it is seen that as the

Cu concentration increases from 0.025 to 0.075 M, the

intensity of prominent peak increases. The intensity of the

peaks was moderately augmented as the Cu concentration was

enhanced along with secondary phases. Similar effects were

also observed by Kermadi et al. during the CZTS formation.[13]

Hence, it is concluded that the secondary phase assists the

formation of CTS film through liquid assisted grain escalation,

resulting in large grains and compact nature of CTS films.

Fig. 1 shows the detailed spectra of the three samples at

diffraction angles, 2θ, around 28º and 47º denoted as (b) and

(c), respectively. The phase assignment and crystallites

orientation were performed using the JCPDS database.

Despite the fact that triclinic Cu2SnS3 and tetragonal phases of

Cu3SnS4 present the peaks close to each other, the detailed

analysis shown allow a clear assignment. In the detailed XRD

patterns of Cu3SnS4 compound at the 2θ close of 28.9º, a

deviation from the JCPDS database value is observed. This

fact may be related to the presence of strain in the sample.[14]

3.2. Raman Analysis

To confirm the crystal structure and phase formation of the

films, Raman spectra of CTS samples were studied. Raman

spectroscopy gives the characteristic vibrational modes of

bulk CTS, other secondary and co-existing phases, which can

be differentiated from each other. The Raman spectra of CTS films deposited with different molar concentrations are shown

in Fig 2. In the Raman spectra, the observed peaks at 252, 291,

318, 322 and 471 cm-1 are related to various optical phonons

modes of CTS phase. As seen in Fig. 2, for the samples S1 and

S2 prepared with 0.025 and 0.050 M concentration, the

observed low-intensity modes at 291 and 320 cm-1 are close to

the reported Raman modes of triclinic CTS.[15] The modes at

291 and 318 cm-1 are endorsed to tetragonal CTS phase, which

is in concurrence with the result reported for Raman analysis

at S3 sample.[9] According to the XRD analysis, these peaks

are attributed to Tetragonal (I-42m) Cu3SnS4.

In addition, the presence of shoulder peak at 291 and 322

cm-1 confirms the formation of tetragonal Cu4SnS4, which is

because of an excess of CuCl2 in the cationic solution.[16] These

results also show the presence of Cu2-xS with the characteristic

Raman peak at 251 and 470 cm-1.[17] With Cu-rich conditions,

the neighboring compound of Cu2SnS3 is Cu3SnS4 in the

Gibbs phase triangle.[18] Cu3SnS4 is relatively stable and can

be grown at room temperature.[19] In fact, the calculated

chemical potential phase space of Cu-Sn-S system showed

that Cu3SnS4 has a wide thermodynamic window of

stability.[20] Thus, the formation of that ternary could also

occur in spite of Cu-rich content compound. The formation of

mixed phase of Cu3SnS4 along with secondary phases of

Cu4SnS4 and Cu2-XS is due to the Cu-rich composition

prepared using the single step SILAR method. Thus, it is clear

that due to different molar concentrations of copper in the

single cationic bath, it is very difficult to deposit CTS thin

films with phase purity and stoichiometric composition.

Fig. 2 Raman spectra of CTS thin films prepared at copper con-

centration: S1 = 0.025 M, S2 = 0.050 M and S3 = 0.075 M.

3.3 SEM Analysis

Fig. 3 shows SEM micrographs of CTS films deposited from

solutions having different copper salt concentrations. The

results show that all the surfaces are homogeneous and mainly

composed of spherical grains with some large sparse clusters

and spherical shape. The micrograph of films deposited from

a solution with 0.025 M copper salt concentration, Fig. 3 (S1),

shows a smeary appearance with large island-like regions. As

the copper salt concentration in the solution is increased up to

0.050 M, distinct grains are seen in the film formed (see Fig.

3 (S2)). When the copper concentration in the solution is

further increased to 0.075 M, agglomeration of the grains is

100 150 200 250 300 350 400 450 500

- Cu3SnS4

- Cu2SnS3

- Cu4SnS4

- Cu2-xS

Inte

nsi

ty (

A. U

.)

S1: 0.025 M

S2: 0.050 M

S3: 0.075 M

Raman shift (cm-1)

S1

S3

S2



found to occur, Fig. 3 (S3). In sprayed CZTS, Kumar et al.[21]

observed similar types of grains increasing in size with

increasing the Cu content. An increase in the surface clusters

with increasing the Cu salt concentration indicates a possible

further reaction of the films on the most active sites,

confirming the aforementioned reports. This effect reaches its

maximum for the 0.075 M sample and proves that the reaction

completion can be different according to the copper content.

The increase of Cu content implies an increase in the mean

grain size from 100 up to 300 nm. It is also useful to mention

that the Cu-poor sample leads to cluster-like aggregates, while

by increasing the copper amount, the aggregates are rounded

and more size-random. This increase in the grain size might be

due to the agglomeration of grains. Increase in grain size

improves the performance of a polycrystalline CTS thin film

with a decrease in grain boundaries that increases the effective

diffusion length of minority carriers.

3.4 Optical analysis

To evaluate the optical band gap for different samples, the

relation between the direct energy gap (Eg) and absorption

coefficient (α) from the Tauc's approximation was shown in

Equation 1:

( )( )

h

EhAn

g−= (1)

where A is a proportionality constant, h is the Planck's constant

and n defines the nature of the radiative transition. In the

present investigation, the values of α are found to obey the

above Equation for n= 1/2, indicating that the optical

transitions are direct-allowed in nature. The effect of Cu

concentration on the optical characteristics such as coefficient

of absorption and band gap of CTS thin film was investigated.

Fig. 4(A) demonstrates the absorption spectra of CTS film

with different Cu concentration. The energy band gap of CTS

thin films was determined from the optical absorption study in

the wavelength having the range of 300–900 nm, which is

important in the design and analysis of various optical devices.

Fig. 4 (B) shows a plot of the square of the product of the

absorption coefficient and photon energy as a function of the

photon energy for the SILAR deposited CTS films with

different Cu concentrations.

The band gap is estimated by extrapolating the straight line

part of the (αhν)2 versus hν curve to the intercept of the

horizontal axis. The values of band-gap for CTS films are

determined to be 1.90, 1.21 and 1.07 eV for 0.025, 0.050 and

0.075 M, respectively. The decrease in the band gap with an

increase in the Cu concentration may be because of: 1)

increase in the crystallinity observed from XRD analysis, 2)

excess of Cu ionsin the cationic bath solution and 3) The

presence of secondary phase Cu4SnS4 carrying a narrow band

gap observed from XRD and Raman analysis. The band gap

tunneling may be understood according to the symmetry of the

valence band maximum (VBM) and conduction band

minimum (CBM) states.[22] It should be noted that the disorder

between Cu and Sn cations is highly possible in the CTS

semiconductors with different compositions, and therefore its

influence on the band gaps is also common.[23]

Fig. 3 SEM images of CTS thin films prepared at copper

concentration: S1 = 0.025 M, S2 = 0.050 M and S3 = 0.075 M.

3.5 Photoelectrochemical cell (PEC) analysis

The PEC performance of the CTS thin films deposited on the

FTO substrates with different Cu concentrations was

investigated using the linear sweep voltammetry (LSV)

measurements. The LSV was performed in a lithium

perchlorate (0.5 M LiClO4) electrolyte under AM 1.5G (100

mWcm-2) illumination using a conventional two electrode

system with a CTS photocathode and graphite as a working

electrode and counter electrode, respectively. The illuminated

J-V curves for CTS based PEC devices fabricated using 0.025,

0.050 and 0.075 M are shown in Fig. 5. The PEC

characterization is selected because it is easier than forming a

solid-state junction. It allows a rapid and nondestructive

S1 S2 S30.025M 0.050M 0.075M

S1 S2 S30.025M 0.050M 0.075M

S1 S2 S30.025M 0.050M 0.075M



evaluation of a photoactivity of the CTS thin films. The

photovoltaic output characteristics of CTS thin films are

analyzed by fabricating FTO/CTS/0.5 M LiClO4/C cell. The

anodic photocurrent was enhanced with the negative potential,

which designates the p-type conductivity of deposited CTS

thin films.[24]

Fig. 4 (A) Optical absorption and (B) Variation of (αhν)2 versus

(hν) plot of CTS thin films prepared at a copper concentration: S1

= 0.025 M, S2 = 0.050 M and S3 = 0.075 M.

Fig. 5 J-V characteristics of CZTS thin films prepared at copper

concentration: S1 = 0.025 M, S2 = 0.050 M and S3 = 0.075 M.

Table 1. Solar cell parameters of PEC devices fabricated for

different copper concentration: S1 =0.025 M, S2 = 0.050 M and

S3 = 0.075 M.

Sr.

N

o

Sampl

e

Jsc

(μA)

Voc

(mV)

Jm

(μA)

Vm

(mV)

Fill

Facto

r FF

(%)

Efficienc

y η (%)

1. S1 79.70 48.00 33.78 28.78 0.254 0.001

2. S2 397.3

4 405.0

5 223.7

7 178.3

9 0.248 0.069

3. S3 460.6

7

521.6

8

267.9

1

214.7

5 0.239 0.114

In the dark, the PEC cell device exhibits diode like

characteristics, which shows an insignificant reverse

saturation current. While the J-V characteristics under

illumination appear the images of a linear plot. These linear

manners of J-V plots are mostly ascribed to the digression

from the stoichiometry, extensively elevated series resistance

of absorber layer and the squat shunt resistance of the PEC

device. The detailed PEC parameters are listed in Table 1. The

significant enhancement in the JSC and VOC is observed with

increasing the Cu concentration upon illumination as shown in

Fig. 5. It can be clearly seen from the graph that the solar cell

based on CTS thin films derived from 0.025 M concentration

denoted by S1 shows a relatively poor performance. This may

be due to an insufficient Cu concentration during the CTS

formation process, which may create structural defects in the

CTS film. While the cell derived from 0.075 M concentration

denoted by S3 exhibits a better conversion efficiency of

0.11 %. From the structural analysis, it is observed that the S3

sample shows a very small secondary phase of Cu2-xS and

Cu4SnS4. The 0.025 and 0.050 M concentration films show a

low efficiency as compared to 0.075 M films.

The fill factor (FF) is lower in the present PEC devices

because of impurities and defects, including insulating

secondary phases, which cause charge carrier recombination.

This effect would be a similar to that of sprayed CZTS thin

films.[25] The short circuit current (JSC) increases with

increasing the Cu concentration. This is due to the improved

and large grain size, which increases the absorption of incident

photons. Additionally, it helps to increase the current

generation and reduce the minority recombination rates.

Similar results are also mentioned by He et al..[26] The

augmentation of these solar cell parameters could be attributed

to the improved morphology of CTS thin films, which affected

the CTS-electrolyte junction quality and dynamics of charge

carrier recombination. Similar effect was introduced by

Suryawanshi et al. during the formation of CZTS thin films.[27]

The photoelectrochemical measurement confirmed the best

photo-activity of the CTS thin films as illustrated in Table 1.

The presence of the secondary phases could affect the

photovoltaic performance. It has been speculated that the

phase separation of CTS into Cu2-xS and Cu4SnS4 compounds

is one of the factors limiting the efficiency of CTS solar cells.

In thin-film solar cells, Cu-rich compounds tend to show poor

power conversion efficiencies due to their higher electrical

conductivity, leading to the shunting problem.[28]

4. Conclusions

In this paper, the effects of copper concentration on structural,

morphological, optical and PEC properties of CTS thin films

have been investigated. The analysis of XRD patterns

indicates that the CTS film with a copper concentration up to

0.075 M have a sharp and intense peak orientation. Further,

Raman studies confirm the formation of mixed phase of

Cu3SnS4 along with secondary phases of Cu4SnS4 and Cu2-XS

due to Cu-rich composition. SEM results indicate that as the

Cu concentration increases, the average grain size also increases. Decrease in band gap due to increase in copper

concentration was confirmed. Furthermore, the solar cell

fabricated with the copper rich CTS film (S3) showed an

enhancement in the conversion efficiency about 0.11%.

Because of the increased number of elements in CTS, their

1.0 1.5 2.0 2.5 3.0 3.5

h (eV)

(h

)2

(eV

)2

S1: 0.025M

S2: 0.050M

S3: 0.075M

(B) Optical band gap

S2

S3

S1

-100 0 100 200 300 400 500 600

-100

0

100

200

300

400

500 S1: 0.025M

S2: 0.050M

S3: 0.075M

S1

S2

S3

Cu

rre

nt

de

ns

ity

(A

/ c

m-1

)

Voltage (mV)



synthesis is more difficult than for binary and ternary

semiconductors. The secondary phases in CTS such as Cu2-XS

and Cu4SnS4 could be formed depending on the processing

conditions. Experimentally, it is found that working devices

are obtained for “Cu-poor” compositions.

Acknowledgement

Authors are thankful to the Department of Science and

Technology-Science and Engineering Research Board (DST-

SERB), New Delhi, India for their financial support through

research Project No. SERB/F/001677/2016-17 dated 13th

January 2017.

Support information

Not applicable

Conflict of Interest

There are no conflicts to declare.

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Author information

Harshad D. Shelke is currently a Ph.D student in Prof. C. D. Lokhande’s group

in Thin Film Physics Laboratory (TFPL)

at Shivaji University Kolhapur. He received his M.Sc. degree from same

University in 2014. He has published 8

papers on Copper based chalcogenide materials with citation over 20 times. His

research focused on the Simple chemical processed Cu2SnS3 thin film solar cell and its optoelectronic

characteristics.

Abhishek C. Lokhande is a

Postdoctoral Fellow of Department of Physics, Khalifa University of Science

and Technology, Abu Dhabi, United

Arab Emirates (UAE). He obtained his Ph.D from Optoelectronic Convergence

Research Centre, Department of

Materials Science and Engineering, Chonnam National University, Gwangju,

South Korea under the supervision of Prof. Jin H. Kim. He has



published over 117 papers on Copper based chalcogenide materials with citation over 2000 times. His current research

focuses on thin film photovoltaics using earth-abudant and

nontoxic materials.

Jin H. Kim is Professor of

Optoelectronic Convergence Research Centre, Department of Materials Science

and Engineering, Chonnam National University, Gwangju, South Korea. His

current research focuses on thin film

photovoltaics, Gas-sensor, Photocatalysis, Li-ion batteries and

Supercapacitor using earth-abundant

and nontoxic materials.

Chandrakant D. Lokhande is a

Research Director of Center for

Interdisciplinary Research Centre, D. Y.

Patil University, Kolhapur. He obtained his Master degree and Ph.D degree from

Shivaji University Kolhapur. He then did his postdoctoral research at Dept. of

Materials Science, WeizmannInstitute of

Science, Rehovot, Israel worked on CuIn chalcogenide thin films. He was honored “Alexander Von-Humboldt

Fellowship,Germany” in 1996-2001 and Nomination for

Shanti Swarap Bhatnager Award by Shivaji University, Kolhapur in 1998 & 1999. He has Patents: (46) (Indian 11

accepted, Korean 5 accepted), Applied (Indian) 29, (Korean) 1, World 01. He has published over 600 papers on various

materials with citated over 50,000 times. His current research

focuses on thin film photovoltaics, Gas-sensor and Supercapacitor using earth-abundant and nontoxic materials. .

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effect of copper content on structural, morphological

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