Green synthesized AgNPs decorated on Ketjen black for enhanced catalytic dye degradation

Article abstract of DOI:10.1007/s11164-020-04290-w

The green synthesis of nanoparticles using plant-based materials as an alternative to chemical and physical routes provides economic and environmental benefits. In the present study, silver nanoparticles (AgNPs) were fabricated using Pseudocydonia sinensis fruit extract. The fabricated NPs were then decorated on commercial Ketjen black-300 (AgNPs@KB-300) and Ketjen black-600 (AgNPs@ KB-600). The synthesized materials were characterized via XRD, FTIR, XPS, SEM-EDX, and HR-TEM studies. The SEM and HR-TEM results revealed that the synthesized AgNPs were spherical and successfully decorated on KB-300 and KB-600. Additionally, the catalytic ability of the synthesized samples during the degradation of methyl orange in the presence of NaBH₄ was studied. Notably, the catalytic activity of AgNPs@ KB-600 was higher than that of AgNPs@ KB-300.

Full text of DOI:10.1007/s11164-020-04290-w

Research on Chemical Intermediates
https://doi.org/10.1007/s11164-020-04290-w
Green synthesized AgNPs decorated on Ketjen black
for enhanced catalytic dye degradation
Rajavaram Ramaraghavulu1 · V. Koteswara Rao2 · K. C. Devarayapalli3 ·
Kisoo Yoo3 · P. C. Nagajyothi3 · Jaesool Shim3
Received: 20 July 2020 / Accepted: 29 September 2020
© Springer Nature B.V. 2020
Abstract
The green synthesis of nanoparticles using plant-based materials as an alternative to
chemical and physical routes provides economic and environmental benefts. In the
present study, silver nanoparticles (AgNPs) were fabricated using Pseudocydonia
sinensis fruit extract. The fabricated NPs were then decorated on commercial Ketjen
black-300 (AgNPs@KB-300) and Ketjen black-600 (AgNPs@ KB-600). The syn-
thesized materials were characterized via XRD, FTIR, XPS, SEM-EDX, and HR-
TEM studies. The SEM and HR-TEM results revealed that the synthesized AgNPs
were spherical and successfully decorated on KB-300 and KB-600. Additionally, the
catalytic ability of the synthesized samples during the degradation of methyl orange
in the presence of NaBH4 was studied. Notably, the catalytic activity of AgNPs@
KB-600 was higher than that of AgNPs@ KB-300.
Keywords Green synthesis · AgNPs · Ketjen black · Methyl orange · Catalytic
activity
Electronic supplementary material The online version of this article (https://doi.org/10.1007/s1116
4-020-04290-w) contains supplementary material, which is available to authorized users.
*
*
P. C. Nagajyothi
nagajyothi@ynu.ac.kr
Jaesool Shim
jshim@ynu.ac.kr
1
2
3
Department of Humanities and Sciences, Annamacharya Institute of Technology and Sciences,
Rajampet, Kadapa 516126, India
Korea Center for Artifcial Photosynthesis, Department of Chemistry, Sogang University,
Seoul 04107, South Korea
School of Mechanical Engineering, Yeungnam University, Gyeongsan 38541, Republic of Korea
Vol.:(0123456789)
1 3

R. Ramaraghavulu et al.
Introduction
Nowadays, it is becoming increasingly crucial to ensure that our environment is
pollution-free. Point source pollution occurs mainly from municipal wastewater
treatment plants and industrial efuents. The discharge of industrial efuents into
water bodies has harmful efects on humans, animals, and aquatic life [1]. Methyl
orange (C14H14N3NaO3S), is an anionic dye that is extensively used in dyeing,
textile, printing, and pharmaceutical industries [2, 3]. When oral consumption,
it is toxic as well as carcinogenic owing to the presence of nitrogen [4]. Various
chemical, physical, and biological methods are used for the degradation of these
dyes. However, the degradation of dyes using green synthesized NPs as a catalyst
in the presence of NaBH4 is an eco-friendly manner.
Among various metal NPs, silver nanoparticles (AgNPs) exhibit high catalytic
activity owing to their size and large surface to volume ratio [5]. Several meth-
ods have been used to synthesize of AgNPs. These include chemical reduction
[6], microwave synthesis [7], photochemical synthesis [8], reverse microemul-
sion polymerization [9], electrochemical [10], biological synthesis using bacteria
and fungus [11, 12], and green synthesis [13, 14]. The green synthesis method is
facile, rapid, and environmentally benign. In addition, green synthesized AgNPs
decorated on carbon-based materials are widely used in various applications such
as photocatalytic (AgNPs/g–C3N4; Ag decorated rGO) [15, 16], catalytic dye deg-
radation (AgNPs/GO) [17], antibacterial (AgNPs/MWCNTs) [18], electrochemi-
cal sensing (AgNPs/rGO) [19], anticancer (AgNPs/rGO) [20], and cytotoxic
(AgNPs/GO) [21], sensing of heavy metals (Ag@rGONCs) [22], and photocata-
lytic bacteria inactivation studies [13].
Carbon-based materials (GO, rGO, g–C3N4, CNTs, QDs, carbon nanofbers,
and Ketjen black) have outstanding physicochemical, thermal, optical proper-
ties, excellent electrical conductivity, corrosion resistance, and inexpensive. Such
materials are generally used as supporters [23–29]. Among the carbon-based
materials, Ketjen black (KB) is a conductive material with a large surface area,
excellent conductivity, and good structural stability [23]. It is widely used as a
supporter in lithium-sulfur batteries (CeO2 nanodots decorated on Ketjen black)
[30], lithium-ion batteries (γ-Fe2O3NP/Ketjen black) [31], glucose electrooxida-
tion (Ketjen black as supports of Pt) [32], oxygen reduction reactions (nitrogen-
doped Ketjen black-supported Co3O4 NPs; MnOx–CeO2/Ketjen black) [23, 33],
hydrogen evolution (Mo2C NPs embedded in Ketjen black) [34], and supercapaci-
tor (Ketjen black supported polyanthraquinone) applications [35].
Pseudocydonia sinensis (Chinese quince; family Rosaceae) is native to East
Asia; it is generally called ‘mugua’ in China, whereas in Korea it is called
‘mogwa’. Its dried fruits have been used in traditional Chinese medicine [36–38].
Green synthesis of metal NPs decorated on carbon materials and the application
of such NPs in catalytic dye degradation has been limited. In this paper, we report
the synthesis of AgNPs using Pseudocydonia sinensis dried fruit as a reducing
agent. The synthesized NPs decorated on commercial Ketjen black 300 and 600
were labeled as AgNPs@KB-300 and AgNPs@KB-600, respectively (Scheme 1).
1 3

Green synthesized AgNPs decorated on Ketjen black for enhanced…
Scheme 1. Synthesis of AgNPs@KB-300 or 600
Furthermore, the synthesized samples were used as catalysts in the degradation of
methyl orange (MO) in the presence of NaBH4. Compared to AgNPs@KB-300,
AgNPs@KB-600 exhibited higher catalytic degradation.
Materials and methods
Synthesis of AgNPs@KB‑300 and AgNPs@KB‑600
First 50 mg of commercial Ketjen black 300 (KB-300) or Ketjen black 600 (KB-
600) was ultrasonically dispersed into 450 mL of double-distilled water for approxi-
mately 60 min. Subsequently, the required quantity of AgNO3 (1 mM) was added
to the KB-300 or KB-600 solution and then stirred for 30 min at room temperature.
Next, 50 mL aqueous extract of dried Chinese quince fruits was added and stirred
10 min and the solution was then kept under direct sunlight for 50 min, and a black
turbid solution was formed. The reduction of metal (Ag+) ions occurred immedi-
ately, and AgNPs@KB-300 and AgNPs@KB-600 formed within 50 min. Synthe-
sized characterization was discussed in the supplementary information.
Catalytic activity
The MO dye was selected for this decolorization experiment. The MO decol-
orization experiment (2 mL; 10 ppm; Sigma-Aldrich) was performed in the pres-
ence of NaBH4 (0.3 mL; 0.2 M; Sigma-Aldrich) and 35 μL aqueous solution of a
1 3

R. Ramaraghavulu et al.
well-dispersed catalyst (2.5 mg/mL). The dye decolorization was monitored by
UV–Visible spectroscopy (Neogen, NEO-D3117).
Results and discussion
Characterization
XRD
Figure 1 shows the XRD pattern of pure KB-300, KB-600, AgNPs@KB-300, and
AgNPs@KB-600 samples. Pure KB exhibited two difraction peaks: one was a week
difraction peak around 43.42°, corresponding to the (100) plane and the second
one was a broad and strong peak located at 24.5°, corresponding to the (002) plane
of the graphite carbon structure. Notably, the (002) peak was wider in the case of
KB-600 than that in the case of KB-300. For the AgNPs@KB-300 and AgNPs@600
sample, the Ag difraction peaks at 2θ=38.17° and 38.41°; 44.48° and 44.60°;
64.68° and 64.80°; 77.42° and 77.77° were attributed to the (111), (200), (220), and
(311) planes, respectively. Furthermore, the size of the crystallite was calculated
using Scherrer’s formula. The calculated crystalline size was~39.0 and~19.0 nm
for AgNPs@KB-300 and AgNPs@KB-600, respectively. In these samples, the Ag
was pure and crystalline, with no other obvious phases present.
The peak broadening induced strain and the size were calculated from the Wil-
liamson-Hall (W-H) plot using the XRD profles. The plots of 4 sin θ with respect to
β cos θ for AgNPs@KB300 and AgNPs@KB600 are shown in Fig. S1. The micro-
strain and crystallite sizes were estimated from the ftted linear curve. The crystallite
Kꢀ
size was calculated from the y−intercept using the relationship y − intercept =
.
Size
Furthermore, the microstrain was calculated using the slope of the ftted curve using
the relationship slope = 4 × strain × sinꢀ. In the present investigation, the crystal-
lite size was estimated from the W-H plot as 30 and 28 nm for AgNPs@KB300
Fig. 1 XRD spectrum of green
synthesized AgNPs decorated
on KB-300 and KB-600
1 3

Green synthesized AgNPs decorated on Ketjen black for enhanced…
and AgNPs@KB600, respectively. Chen et al. [39] and Xie et al. [40] suggested
that nano-crystallization also has an excellent degradation efect. The estimated
microstrain for the AgNPs@KB600 and AgNPs@KB300 samples was 0.0052 and
0.00033, respectively. The slopes positively refected the tensile strain present in the
samples.
FT‑IR
The functional groups of the AgNPs@KB-300 and AgNPs@KB-600 were deter-
mined via FT-IR spectroscopy. In KB-300 and 600, the peak close to 1600 cm−1
was attributed to the C=C stretching vibration, whereas the peaks at approximately
1050 cm−1 corresponded to the C–O stretching [41] (Fig. S2). The FT-IR spectra
of AgNPs@KB-300 and AgNPs@KB-600 are shown in Fig. S3. Some prominent
AgNPs@KB-300 and AgNPs@KB-600 peaks were observed at 2670 cm−1 and
2659 cm−1; 2349 cm−1 and 2364 cm−1; 1272 cm−1 and 1265 cm−1; and 846 cm−1 and
842 cm−1, respectively. These were related to the C–H alkane stretching, O=C=O
carbonyl bond group stretching, C–N stretching amines, and C=CH2 groups, respec-
tively [42–44]. After the green synthesized AgNPs were decorated onto KB-300 and
600, C=C, C–O functional groups were still present with slight changes.
Morphological studies
The SEM images revealed the spherical shape of the AgNPs attached to the surfaces
of KB-300 and KB-600. For, both samples, most of the nanoparticles were spherical
(Fig. 2ai–iii, bi–iii). The EDX and elemental mapping indicated the presence of Ag
and C (2a iv–vi and b-iv–vi). Therefore, these results confrmed that the green syn-
thesized AgNPs were successfully attached to KB-300 and KB-600.
Figure 3 shows the TEM images of the pristine KB-300 (Fig. S4 a and b),
KB-600 (Fig. S4 c and d), AgNPs@KB-300, and AgNPs@KB-600 samples, respec-
tively. Both pristine KB-300 and KB-600 showed a similar sheet-type and porous
sphere-like morphology. In both AgNPs@KB-300 and AgNPs@KB-600 samples,
the green synthesized AgNPs decorated were eventually (3a i–ii and bi–ii). Further-
more, the lattice fringes of 0.242 nm in spacing corresponded to the (111) plane of
Ag (3 a-iii and b-iii). The corresponding line profles are shown in Fig. S5 and Fig.
S6 for AgNPs@KB-300 and AgNPs@KB-600, respectively. Hence, it is evident that
AgNPs were decorated on the surfaces of KB-300 and KB-600.
XPS
XPS technique was carried out to identify and confrm the chemical state of
AgNPs@KB-600. The XPS analysis was carried out only on one sample (AgNPs@
KB-600), and the results are shown in Fig. 4. The survey scan spectra of AgNPs@
KB-600 are shown in Fig. 4a, which reveals the presence of Ag and C with an
additional peak of O. To obtain more information regarding the Ag and C met-
als, we performed high-resolution XPS analysis. Figure 4b shows the deconvo-
luted high-resolution XPS spectra of C, which contained three dominant peaks at
1 3

R. Ramaraghavulu et al.
Fig. 2 SEM images of AgNPs@KB-300 (ai–aiii), AgNPs@KB-600 (bi–biii), EDX spectra of AgNPs@
KB-300 (a-iv), AgNPs@KB-600 (b-iv), and elemental mapping of AgNPs@KB-300 (a-v and b-vi) and
Ag@KB-600 (b-v and b-vi)
Fig. 3 Low-magnifcation TEM images of AgNPs@KB-300 (a-i), AgNPs@KB-600 (b-i), high magni-
fcation HR-TEM images of AgNPs@KB-300 (a-ii), AgNPs@KB-600 (b-ii), and d-spacing values of
AgNPs@KB-300 (a-iii) and AgNPs@KB-600 (b-iii)
1 3

Green synthesized AgNPs decorated on Ketjen black for enhanced…
Fig. 4 XPS spectra of AgNPs@KB-600 (a); survey scan and high-resolution scans spectra of C 1 s (b)
and Ag 3d (c)
various binding energies. The peaks observed at binding energies of 284.7, 285.9,
and 290.6 eV were attributed to C–C, C=C, and ꢀ − ꢀ∗ groups, respectively [45].
Figure 4c shows the high-resolution XPS spectra of Ag 3d. Particularly, the spectra
exhibit doublet peaks which arose from the spin–orbit coupling Ag 3d3/2 and Ag
3d5/2; the corresponding peaks are located at 373.5 and 367.5 eV, respectively. The
splitting of the 3d doublet of Ag was approximately 6.0 eV, indicating that Ag was
formed on the surface of Ketjen black [46].
Figure 5 shows the BET surface analysis of AgNPs@KB-300 and AgNPs@
KB-600. The BET surface area was found to be 225.89 m2 g−1 with a pore volume
of 0.578108 cm3 g−1 for AgNPs@KB-300 and 288.97 m2 g−1 with a pore volume
of 0.640988 cm3 g−1 for AgNPs@KB-600. The AgNPs@KB-600 had the largest
surface area (288.97 m2 g−1), which can afect the catalytic dye degradation activity.
Catalytic studies
Water pollution is mainly caused by industrial efuents, which contain various
organic dye pollutants and toxic metals, these are harmful to organisms. Cata-
lytic degradation is a suitable way to decompose toxic dyes. This method is
1 3

R. Ramaraghavulu et al.
Fig. 5 BET surface area of green synthesized AgNPs, AgNPs@KB300 (above) and AgNPs@KB600
(below) nitrogen adsorption–desorption isotherms (inset: corresponding pore-size distribution)
simple, rapid, and inexpensive. In this study, MO was selected as a model pollut-
ant to examine the catalytic activity of the KB-300, KB-600, AgNPs@KB-300,
and AgNPs@KB-600 nanocatalysts, with sodium borohydride (NaBH4) under
ambient conditions. MO shows a strong absorption peak of~ 464 nm owing to
the absorption exhibited by the azo group. Furthermore, a weak absorption peak
at 272 nm was ascribed to the ꢀ − ꢀ∗ transition in the aromatic rings [47]. Fig-
ure 6 shows the UV–visible spectrum of the catalytic activity compression of
the synthesized samples. The KB-300 (Fig. 6a) and KB-600 (Fig. 6b) samples
showed ~ 45 and ~ 50% degradation, respectively, within 14 min, in the presence
of NaBH4. Moreover, the dye decolorization occurred rapidly in the presence of
the AgNPs@KB-300 (Fig. 6c) and AgNPs@KB-600 (Fig. 6d), and NaBH4 in the
reaction solution (MO dye) owing to the increase of electron transfer from cata-
lyst to the dye. The percentage of degradation of dye was calculated using the
following equation:
Co − C
% degradation =
× 100
(1)
Co
where Co is the initial concentration of dye before illumination and C is the con-
centration of the dye after time t. The Langmuir–Hinshelwood pseudo-frst-order
kinetic model equation was used to determine the rate constant according to the fol-
lowing equation [48]:
1 3

Green synthesized AgNPs decorated on Ketjen black for enhanced…
Fig. 6 Time-dependent of MO UV–Visible spectrum on NaBH4 in the presence of KB-300 (a), KB-600
(b), AgNPs@KB-300 (c), and AgNPs@KB-600
(
)
C
ln
= −kt
(2)
Co
where k is the apparent frst-order rate constant (min−1), and t is the time interval.
The MO dye decolorization performance of the green synthesized catalysts (KB-
300, KB-600, AgNPs@KB-300, and AgNPs@KB-600) is shown in Fig. 7a. This
fgure reveals that AgNPs@KB-600 exhibited excellent MO dye decolorization
Fig. 7 MO dye degradation efciency of green synthesized AgNPs on KB-300 and KB-600 (a) and rate
constant plots of green synthesized AgNPs on KB-300 and KB-600 (b)
1 3

R. Ramaraghavulu et al.
Fig. 8 Schematic illustration of MO degradation process in the presence of green synthesized AgNPs on
KB-300 and KB-600
owing to the large surface area of KB-600. The rate constants corresponding to
the green synthesized catalysts AgNPs@KB-300 and AgNPs@KB-600 along with
KB-300 and KB-600 are shown in Fig. 7b. These were 0.0782, 0.0966, 0.320 and
0.622 min−1, respectively. When the AgNPs@KB-300and AgNPs@KB-600 nano-
catalysts were added to MO solution, the color of the solution changed from orange
to colorless within 10 and 6 min, respectively. The 464 nm and 272 nm peaks also
almost disappeared, indicating the complete decomposition of the MO molecules.
AgNPs@KB-300 and AgNPs@KB-600 exhibited~99% MO degradations in 10 min
and 6 min, respectively, owing to the high surface area of KB-600 and because the
AgNPs well decorated. The rate constant corresponding to AgNPs@KB-600 was
substantially higher than that corresponding to KB-300 and KB-600. This indicated
the infuence of the AgNPs on the surface of the Ketjen black.
A possible mechanism pathway of MO dye by the AgNPs@KB-600 nanocata-
lyst in the presence of NaBH4 is illustrated in Fig. 8. In the suggested mechanism,
carbon-based materials serve as a co-catalyst, prevent the aggregation. They also
provide basic sites that promote the electron (e−) transfer from the catalyst, which
improves the catalytic activity [49]. The MO dye is electrophilic, whereas BH4− ions
are nucleophilic and can adsorb on the surface of the catalyst. AgNPs@KB-600
accepts electrons from the BH4− and transfer it to the adsorbed MO molecules fastly
[50]. The uptake e− leads to the degradation of MO via an oxidation–reduction reac-
tion [51, 52]. In this manner, the catalytic reduction process comprises e− transfer
−
from the BH4 to the adsorbed MO dye through the AgNPs@KB-600 nanocatalyst
surface in aqueous media [50, 52–54].
Conclusion
In this study, plant-based AgNPs were decorated on KB-300 and KB-600 for cat-
alytic methyl orange dye degradation. AgNPs@KB-300 and AgNPs@KB-600
showed an excellent catalytic dye degradation of approximately 99%. The reac-
tion was completed within 6 min. Hence, we believe that the synthesized AgNPs@
KB-300 and AgNPs@KB-600 could be used as green catalysts to treat wastewater
generated from dyeing.
Acknowledgements This research was reinforced by the National Research Foundation of Korea (NRF)
(2018R1A2B6006056 and 2020R1A2C1012439)
1 3

Green synthesized AgNPs decorated on Ketjen black for enhanced…
References
1. B. Lellis, C.Z. Fávaro-Polonio, J.A. Pamphile, J.C. Res. Innoavat. 3, 275 (2019)
2. E. Bazrafshan, A.A. Zarei, H. Nadi, M.A. Zazouli, Ind. J. Chem. Technol. 21, 105 (2014)
3. A. Mittal, A. Malviya, D. Kaur, J. Mittal, L. Kurup, J. Hazard. Mater. 148, 229 (2007)
4. B. Lellis, C.Z.F. Polonio, J.A. Pamphile, J.C. Polonio, Biotechnol. Res. Innovation 3, 275 (2019)
5. B. Vellaichamy, P. Periakaruppan, Silver nanoparticle-embedded RGO-nanosponge for superior
catalytic activity towards 4-nitrophenol reduction. RSC Adv. 6, 88837 (2016)
6. C.Q. Quiroz, N.A.J.Z. Giraldo, L.E. Botero, J. Quintero, D.Z. Triviño, J. Saldarriaga, V.Z. Pérez,
Biomat. Res. 23, 27 (2019)
7. S. Kondaiah, G. Bhagavanth Reddy, P. Babu, K. Kishore Kumar, G. Narasimha, J. Nanostr.
Chem. 8, 179 (2018)
8. Z. Zhao, N. Chamele, M. Kozicki, Y. Yao, C. Wang, J. Mater. Chem. C 7, 6099 (2019)
9. M. Wang, C. Liu, H. Yang, J. Li, X. Ren, Poly. Comp. 35, 1325 (2014)
10. M. Starowicz, B. Stypula, J. Banaś, Electrochem. Commu. 8, 227 (2006)
11. S. Gurunathan, Arabian J. Chem. 12, 168 (2019)
12. G. Krishna, V. Pranitha, M.A. Singara Charya, Open Nano 2, 64 (2017)
13. P.C. Nagajyothi, L. Veeranjaneya Reddy, K.C. Devarayapalli, S.V. Prabhakar Vattikuti, Y.J. Wee,
J. Shim, J. Cluster Sci. (2020). https://doi.org/10.1007/s10876-020-01821-8
14. Y. He, F. Wei, Z. Ma, H. Zhang, Q. Yang, B. Yao, Z. Huang, J. Li, C. Zenga, Q. Zhang, RSC
Adv. 7, 39842 (2017)
15. P.C. Nagajyothi, M. Pandurangan, S.V.P. Vattikuti, C.O. Tettey, T.V.M. Sreekanth, J. Shim, Sep.
Purif. Technol. 188, 228 (2017)
16. P. Parvathi Ameena Jose, M.S. Kala Nandakumar Kalarikkal, S. Thomas, Res. Chem. Intermed.
44, 5597 (2018)
17. T.V.M. Sreekanth, M.-J. Jung, I.-Y. Eom, Appl. Surf. Sci. 361, 102 (2016)
18. S. Mohan, O.S. Oluwafemi, S.P. Songca, D. Rouxel, P. Miska, F.B. Lewu, N. Kalarikkal, S.
Thomas, Pure Appl. Chem. 88, 71 (2016)
19. C. Karuppiah, K. Muthupandi, S.M. Chen, M. Ajmal Ali, S. Palanisamy, A. Rajan, P. Prakash,
FahadMA Al-Hemaid, B.S. Lou, RSC Adv. 5, 31139 (2015)
20. S. Gurunathan, J.W. Han, J.H. Park, E. Kim, Y.J. Choi, D.N. Kwon, J.H. Kim, Int. J. Nanomed.
10, 6257 (2015)
21. T.V.M. Sreekanth, M. Pandurangan, Y.R. Min-Ji Jung, I.-Y. Lee, Res. Chem. Intermed. 45, 5665
(2016)
22. P.O. Patil, P.V. Bhandari, P.K. Deshmukh, S.S. Mahale, A.G. Patel, S.B. Bari, Res. Chem.
Intermed. 43, 3757 (2017)
23. G. Cheng, G. Liu, P. Liu, L. Chen, S. Han, J. Han, F. Ye, W. Song, B. Lan, M. Sun, L. Yu, Front.
Chem. 7, 766 (2019)
24. Y. Liang, Y. Li, H. Wang, J. Zhou, J. Wang, T. Regier, H. Dai, Nat. Mater. 10, 780 (2011)
25. Y. Tong, S. Bohm, M. Song, Austin J. Nanomed. Nanotech. 1, 1003 (2014)
26. Y. Chen, X. Bai, Catalysts 10, 142 (2020)
27. F. Alimohammadi, M.P. Gashti, A. Shamei, A. Kiumarsi, Superlatt. Microstru. 52, 50 (2012)
28. R.S. Das, S.K. Warkhade, A. Kumar, A.V. Wankhade, Res. Chem. Intermed. 45, 1689 (2019)
29. R. Cardeña, B. Cercado, G. Buitrón, Biohydrogen, 159 (2019)
30. X. Qian, L. Jin, L. Zhu, S. Yao, D. Rao, X. Shen, X. Xi, K. Xiao, S. Qin, RSC Adv. 6, 111190
(2016)
31. H. Dong, Y. Xu, M. Ji, H. Zhang, Z. Zhao, C. Zhao, Electrochim. Acta 151, 118 (2015)
32. Y. Holade, C. Morais, K. Servat, T.W. Napporn, K. Boniface Kokoh, Phys. Chem. Chem. Phys.
16, 25609 (2014)
33. J. Chen, N. Zhou, H. Wang, Z. Peng, H. Li, Y. Tang, K. Liu, Chem. Commun. 51, 10123 (2015)
34. D. Wang, J. Wang, X. Luo, Z. Wu, L. Ye, ACS Sustain. Chem. Eng. 6, 983 (2018)
35. Y. Zhou, B. Wang, C. Liu, N. Han, X. Xu, F. Zhao, J. Fan, Y. Li, Nano Energy 15, 654 (2015)
36. Y. Hamauzu, C. Kume, H. Yasui, T. Fujita, J. Agri. Food Chem. 55, 1221 (2007)
37. E.K. Essuman, P.C. Nagajyothi, C.O. Tettey, J. Med. Plants Stud. 5, 175 (2017)
38. P.C. Nagajyothi, T.V.M. Sreekanth, K.D. Lee, Synth. React. Inorg. Metal-Org., Nano-Metal
Chem. 42, 1339 (2012)
1 3

R. Ramaraghavulu et al.
39. S. Chen, G. Yang, S. Luo, S. Yin, J. Jia, Z. Li, S. Gao, Y. Shao, K. Yao, J. Mater. Chem A 5, 14230
(2017)
40. S. Xie, Y. Xie, J.J. Kruzic, K. Gu, H. Yang, Y. Deng, X. Zeng, Chem. Cat. Chem. 12, 750 (2020)
41. C.D. Zappielo, D.M. Nanicuacua, W.N.L. dos Santos, D.L.F. da Silva, L.H. Dall’Aantônia, F.M. de
Oliveira, D.N. Clausen, C.R.T. Tarley, J. Braz. Chem. Soc. 27, 1715 (2016)
42. Md Amdadul Huq, Int. J. Mol. Sci. 21, 1510 (2020)
43. K. Jyothi, M. Baunthiyal, A. Singh, J. Rad. Res. Appl. Sci. 9, 217 (2016)
44. P. Devaraj, P. Kumari, C. Aarti, A. Renganathan, J. Nanotechnol. 2013, 598328 (2013)
45. Y. Xu, J. Chen, Z. Xiao, C. Ou, W. Lv, L. Tao, S. Zhong, Nanoscale 11, 15881 (2019)
46. J. Li, L. Kang, B. Wang, K. Chen, X. Tian, Z. Ge, J. Zeng, J. Xu, W. Gao, ACS Sustain. Chem. Eng.
7, 1146 (2019)
47. M. Hou, F. Li, X. Liu, X. Wang, H. Wan, J. Hazard. Mat. 145, 305 (2007)
48. G.R. Dillip, T.V.M. Sreekanth, S.W. Joo, Ceram. Inter. 43, 6437 (2017)
49. F. Xiao, H. Ren, H. Zhou, H. Wang, N. Wang, D. Pan, ACS Appl. Nano Mater. 2, 5420 (2019)
50. A. Ucar, M. Findik, I.H. Gubbuk, N. Kocak, H. Bingol, Mat. Chem. Phy. 196, 21 (2017)
51. S. Li, H. Li, J. Liu, H. Zhang, Y. Yang, Z. Yang, L. Wang, B. Wang, Dalton Trans. 44, 9193 (2015)
52. G. Fu, L. Tao, M. Zhang, Y. Chen, Y. Tang, J. Lin, T. Lu, Nanoscale 5, 8007 (2013)
53. P.K. Sahoo, D. Thakur, D. Bahadur, B. Panigrahy, RSC Adv. 6, 106723 (2016)
54. B. Vellaichamy, P. Periakaruppan, RSC Adv. 6, 31653 (2016)
Publisher’s Note Springer Nature remains neutral with regard to jurisdictional claims in published
maps and institutional afliations.
1 3