Kamaraj Sathish-Kumar | Centro de Investigacion y Estudios Avanzados del IPN (original) (raw)

Papers by Kamaraj Sathish-Kumar

Materials Science in Semiconductor Processing, 2020

Abstract Photocatalytic generation of hydrogen (H2) using semiconductor junctions is an effective... more Abstract Photocatalytic generation of hydrogen (H2) using semiconductor junctions is an effective and sustainable way to produce H2. One challenge in photocatalytic systems is to promote an effective separation of charges and reduce charge recombination to enhance overall performance of the photocatalytic system. In the present work, MoS2- TiO2-reduced graphene oxide (MTG) and CeO2-Ce2Ti3O8.7-TiO2-reduced graphene oxide (CTG) composites were synthesized through hydrothermal route using a KOH pretreatment on the TiO2 nanoparticles before Mo or Ce incorporation, in order to increase reactivity and defects such as oxygen vacancies. The structural analysis done by X-ray diffraction and Raman spectroscopy reveals the formation of KTi8O16.5 traces, TiO2 and rGO in MTG as well as rGO, CeO2, Ce2Ti3O8.7 and TiO2 phases in CTG. From high resolution transmission electron micrographs, the composite phases were identified. In MTG, well defined graphene, TiO2 and MoS2 phases were observed. In CTG, CeO2 nanoparticles nucleated onto Ce2Ti3O8.7. XPS analysis reveals the presence of oxygen vacancies and Ti3+ in TiO2 both in CTG and MTG, Mo2+ and Mo4+ in MTG, and Ce4+ and Ce3+ in CTG, respectively. From optical absorption, band gap of 3.3 eV and 3.4 eV was found for CTG and MTG respectively. CTG shows an extended absorption tail that would arise from Ce3+ induced defects within the band gap. Photoluminescence confirmed the presence of MoS2 and defect states both in MTG and CTG. From the structural, chemical and optical data, electronic band diagrams are proposed to explain the mechanisms of H2 evolution in the composites. The homojunction due to the presence of rutile and anatase in the commercial TiO2 nanoparticles improves charge separation in TiO2. The oxygen vacancies in Ce2Ti3O8.7 and Ti3+ in TiO2 as well as the sulphur vacancies in MoS2 create interband defect states below conduction bands of the respective semiconductors that trap the photoelectron, which leads to prolonging the lifetime of charge carriers, resulting in reduced charge recombination. The presence of defect states in the TiO2–Ce2Ti3O8.7-CeO2 interfaces create extended absorption below the TiO2 bandgap. The presence of the graphene boosted charge transport in composites and acted as a co-catalyst to photogenerate the H2, presumably because the work function value of rGO with respect to that of H2 evolution reaction as well as to its electron donor character. Observed H2 evolution rates in MTG and CTG were 363.83 μmolg−1h−1and 355.9 μmolg−1h−1 respectively, under 254 nm illumination. The photocatalytic activity of the CTG composite was reported for the first time. The KOH pretreatment on TiO2 nanoparticles effectively increased the H2-photogeneration with respect to previous reports.

Journal of Experimental Biology and Agricultural Sciences

Plant microbial fuel cell (Plant-MFC) is an emerging technology that uses the metabolic activity ... more Plant microbial fuel cell (Plant-MFC) is an emerging technology that uses the metabolic activity of electrochemically active bacteria (EABs) to continue the production of bioelectricity. Since its invention and to date, great efforts have been made for its application both in real-time and large-scale. However, the construction of platforms or systems for automatic voltage monitoring has been insufficiently studied. Therefore, this study aimed to develop an automatic real-time voltage data acquisition system, which was coupled with an ATMEGA2560 connected to a personal computer. Before the system operation started it was calibrated to obtain accurate data. During this experiment, the power generation performance of two types of reactors i.e. (i) Plant-MFC and (ii) control microbial fuel cell (C-MFC), was evaluated for 15 days. The Plant-MFC was planted with an herbaceous perennial plant (Stevia rebaudiana), electrode system was placed close to the plant roots at the depth of 20 cm. ...

Venkatasamy Vignesh, Ganesan Sathiyanarayanan, Karuppaiah Parthiban, Kamaraj Sathish Kumar and Ra... more Venkatasamy Vignesh, Ganesan Sathiyanarayanan, Karuppaiah Parthiban, Kamaraj Sathish Kumar and Ramasamy Thirumurugan* Laboratory of Aquabiotics/Nanoscience, Department of Animal Science, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India Department of Biological Engineering, College of Engineering, Konkuk University, Seoul, Korea Engineering in Energy Department, Polytechnic University of Aguascalientes, Calle Paseo San Gerardo No 207, Fracc San Gerardo C P 20342, Aguascalientes, Ags, Mexico Aquatic Animal Nutrition, School of Fisheries, Aquaculture and Aquatic Sciences, Auburn University, 203 Swingle Hall, Auburn, USA

Sustainable Agriculture towards Food Security, 2017

The diverse capacity of microbial fuel cells (MFCs) lies in the catabolization of complex/simple ... more The diverse capacity of microbial fuel cells (MFCs) lies in the catabolization of complex/simple organic substrates into electricity with the aid of microbial communities and their interactions. One of the most promising types is plant-based MFCs (P-MFCs), whose benefits allow direct generation of electricity while growing the plants. Since a decade, P-MFCs have been intensively researched and developed, leading to an expansion of their functionalities and improvements in their performance, employing cost-effective materials. The power densities have been amplified mainly due to improvements in the setup construction, operation, and materials, which overcome the system restrictions. Moreover, P-MFCs could be operated with a nitrogen removal system incorporated into the cathodic electron acceptor, which would represent some advantages compared with oxygen as the final terminal electron acceptor. Accordingly, P-MFCs might be a future energy-efficient and economical solution for sustainable agriculture processes and wetland-based wastewater treatment methods. This chapter presents the technologies available in MFCs with a summary of their merits and feasible applications in the near future. Plant-mediated bioelectricity will be an alternative source of generating power throughout the world.

Journal of New Materials for Electrochemical Systems, 2012

A single-chamber microbial fuel cell (SCMFC) with a carbon supported Pt-cathode for the oxygen re... more A single-chamber microbial fuel cell (SCMFC) with a carbon supported Pt-cathode for the oxygen reduction reaction (ORR), and loaded with a sulfate reducing bacterial consortium as biocatalyst in the anodic chamber was characterized by polarization by variable resistance (VR) and linear sweep voltammetry (LSV) methods. From VR a whole cell configuration maximum volumetric power of 92.5 mW m-3 was attained at a current density of 459 A m-3 and voltage of 0.202 V. The LSV method of whole cell configuration gave a higher maximum power density of 197.5 mW m-3 at current density of 696 mA m-3 at the potential of 0.284V; this disagreement was ascribed to possible reduction of power and potential overshoot with the LSV. There was a fair agreement between internal resistance values of whole cell configuration determined by VR and electrochemical impedance spectroscopy (EIS): 2225 and 2307 Ω , respectively. Yet, internal resistance measured by LSV was 30% lower for the whole cell configuratio...

International journal of electrochemical science

A novel intermittent microwave assisted method was developed for surface impregnation and electri... more A novel intermittent microwave assisted method was developed for surface impregnation and electrical properties improvement of decorated activated carbon (DAC), from commercially available activated carbon (AC) and Vulcan carbon (VC). These materials were characterized by UV-visible spectroscopy, Raman spectroscopy, X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM) and electrical conductivity. The UV absorption peak in carbon materials is related to electronic transitions between the bonding and antibonding π orbital. Raman spectroscopy and XRD results showed that the higher disorder of amorphous carbon phase arose in DAC, when compared to typical AC. Results from BET analysis had relatively high surface area of 1141m 2 /g and total pore size volume of 0.524 m 3 /g for DAC. SEM analysis revealed that undefined structure of activated carbon material (~1-3 µm in size) breakage into ~ 100 nm in size over this Vulcan carbon material (~60nm in size...

The Analyst, 2010

An electrochemical assay for sensing NO in biological systems is described in this paper. The fer... more An electrochemical assay for sensing NO in biological systems is described in this paper. The ferrocene mediated reduction of NO, facilitated by the gold nanocomposite modified glassy carbon electrode is followed by an amperometric procedure. The analytical protocol involves the modification of a glassy carbon electrode by an overlayer of Au nanocomposites prepared through galvanic reduction. Additional overlayers can be built on the surface by repetition of the procedure. The modification leads to the decrease of the ...

International Journal of Hydrogen Energy, 2013

Environmental Science & Technology, 2009

Applied Biochemistry and Biotechnology, 2008

ACS Applied Materials & Interfaces, 2011

This work describes a bioassisted approach for the preparation of metal nanoparticles using yeast... more This work describes a bioassisted approach for the preparation of metal nanoparticles using yeast species Hansenula anomala. Gold nanoparticles were prepared using gold salt as the precursor, amine-terminated polyamidoamine dendrimer as the stabilizer, and the extracellular material from H. anomala as the bioreductant. It could also be demonstrated that, using our approach, small molecules such as cysteine can act as stabilizers as well. This synthetic approach offers a greener alternative route to the preparation of gold sols that are devoid of cellular and toxic chemical components. The ability of as-synthesized gold sol to function as biological ink for producing patterns for the analysis of fingerprints and to act as an antimicrobial reagent is evaluated. The generality of this toxin-free synthetic approach to other metals was assessed using palladium and silver.

In the present study, we report the formulation, characterization, and in vitro antibacterial and... more In the present study, we report the formulation, characterization, and in vitro antibacterial and cytotoxicity effects of exopolysaccharide (EPS) stabilized iron oxide nanoparticles (FeONPs) against the human epidermoid carcinoma cell line (A431). EPS is extracted from a spore-forming strain of Bacillus subtilis, VT03, isolated from the gut microbiome of the freshwater fish Oreochromis mossambicus (Tilapia). FTIR, 1 H NMR and 13 C NMR spectroscopic studies show the presence of sugar moieties, confirming that EPS might be a glucan. Later, EPS is used as an eco-friendly reducing and stabilizing agent for the formulation of iron oxide nanoparticles (FeONPs). Initially, the generation of nanoscale FeO was confirmed through the formation of a black-coloured precipitate with an absorbance maxima at 250– 300 nm in a UV-visible spectrometer. X-ray diffraction (XRD) planes clearly confirm that the synthesized FeONPs are in the cubic spinel phase. The morphometric features of the synthesized FeONPs are exclusively studied using electron microscopy (FESEM and HRTEM) which shows spherical FeONPs in sizes ranging between 75–120 nm; the mean size was found to be 106 AE 12 nm. Additionally, energy dispersive X-ray analysis (EDAX), selected area emission diffraction (SAED) and dynamic light scattering (DLS) confirms the purity and homogeneity of the synthesized FeONPs. The vibrating sample magnetometer (VSM) technique reveals the presence of both ferro-and antiferromagnetic phases in the EPS-stabilized FeONPs. Further, the inhibitory activity of EPS-stabilized FeONPs against human and fish pathogenic strains such as Aeromonas hydrophila (ATCC 49140), Aeromonas hydrophila (MTCC 1739), Aeromonas sobria (MTCC 3613) and Aeromonas hydrophila (obtained from OIE Reference Laboratory, C. Abdul Hakeem College, Melvisharam) was assessed. The in vitro cytotoxicity effects of free EPS and EPS-stabilized FeONPs were probed in the human epidermoid carcinoma cell line A431. The IC 50 values of EPS and EPS-stabilized FeONPs were found to be 350.18 and 62.946 mg ml À1 respectively. Further, acridine orange/ethidium bromide (AO/EtBr) staining of A431 cells at different time intervals clearly distinguishes the live cells and the cells that have undergone apoptotic cell death. In conclusion, our research paves the way for a facile and greener route to synthesize FeONPs at room temperature. On the other hand, this study also proves that the formulated multifunctional hybrid FeONPs have remarkable qualities such as enhanced bioavailability and magnetic properties. This can be developed into a successful theragnostic platform for cancer treatment.

Environmental engineering and management journal

Suitable microbes for microbial fuel cells (MFC) can be selected by the different redox potential... more Suitable microbes for microbial fuel cells (MFC) can be selected by the different redox potentials of electron acceptors and methods, such as use of (i) internal electron acceptor (such as fumarate), (ii) external electron acceptor such as insoluble Fe (III), and (iii) solid electrode with an internal electron acceptor. Therefore, the objective of this study was to compare a chemical (final terminal electron acceptor –Fe(III)) and an electrochemical enrichment methods of a saline-sodic soil inoculum. An alkalophilic inoculum was obtained from saline-sodic soil of the former Texcoco lake, Mexico City. A lab scale single-chamber microbial fuel cell was built as reported elsewhere. Electrochemical impedance spectrum (EIS), linear sweep voltammetry (LSV), and Cyclic voltammetry (CV) experiments were performed as previously described. The Chemical (C) and Electrochemically (E) enrichment methods were carried out as reported elsewhere. The C-enrichment was performed in successive cultures...

Abstract Anode-respiring bacteria (ARB) perform an unusual form of respiration in which their ele... more Abstract Anode-respiring bacteria (ARB) perform an unusual form of respiration in which their electron acceptor is a solid anode. The focus of this study was to characterize the electrical stress direct evolution of biocatalysts as a way of enriching the community with ARB for microbial fuel cell. We gave the electrical stress continually to the Texcoco bacterial community at-150mV/SCE. The 4th day current started to increase and attained the maximum current of 0.35 mA in the 15 th day.

International Journal of Hydrogen Energy

In microbial fuel cells (MFCs) efficient extracellular electron transfer microbes, also known as ... more In microbial fuel cells (MFCs) efficient extracellular electron transfer microbes, also known as anode-respiring bacteria, play an important role on cell performance. This type of microbes can be developed by application of enrichment procedures. The objective of this study was to compare a chemical (only C, final terminal electron acceptor Fe(III)), an electrochemical (only E), and a hybrid method (H, i.e., E followed by 3 serial transfers in iron (III) citrate medium) enrichment methods departing from a saline–sodic soil inoculum. In the electrochemical enrichment procedure in an electrolysis cell, the inoculum was subjected to a continuous electrical stress continually by posing the cell at −150 mV/SCE (+94 mV/SHE). The only C enrichment method delivered powers superior to the only E one (higher values of PAn,max = 49 mW m−2 and PV,max = 558 mW m−3 of C compared to 33 and 379 of only E). Interestingly, overall resistance as determined by EIS was lower for only E (1240 Ω) than for only C (1632 Ω). Yet, the hybrid H method, showed electrochemical characteristics consistently superior to both only C and only E methods (higher PAn,max and PV,max, lower internal resistance). Further detailed electrochemical studies of only E-method showed that the anodic resistance decreased with the time of operation of the electrolysis cell that would be consistent with the adaptability/enrichment purpose of the method. Also, Cyclic voltammetry peaks with values close to those reported for bacterial cytochromes appeared with time of cell operation.To the best of our knowledge, this is the first time that it is reported that serial transfers with Fe(III) as electron acceptor to an inoculum previously enriched in an electrolysis cell, leads to improved characteristics of MFC and increased Fe(III)-reducing capability of the inoculum.► Evaluation of 3 enrichment methods of a saline–sodic soil for using in MFC. ► They were chemical (C), electrochemical (E), a hybrid method (E followed by C). ► E adaptability/enrichment of the inoculum associated to anodic resistance decrease. ► Hybrid method gave superior characteristics of the tested microbial fuel cell. ► First time a successful hybrid method of enrichment is reported in the literature.