Faculty Publications
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Item Advanced 2D materials for biohydrogen purification(Elsevier, 2025) Prabhakar, N.; Isloor, A.M.; A.F., A.F.Accumulation of waste on the planet has risen to a peak due to elevating industrialization and urbanization on demand of bursting population growth. Outcomes are severe, including global warming, disease outbreaks, the greenhouse effect, and unpredictable natural calamities. It is, therefore, necessary to think about ways to convert the accumulated waste into some useful form. The growing population needs energy for its life-sustaining activities. Energy production from fossil fuels can lead to undesirable climate change. Potential applications such as powering proton exchange membrane fuel cells can be achieved using biohydrogen. Hydrogen is one of the clean, renewable alternative sources of energy that can be derived from waste. This review discusses the various ways of obtaining clean hydrogen from waste, especially using advanced two-dimensional materials. The role of boron-nitrides, layered double hydroxides, graphene oxide derivatives, two-dimensional covalent organic and metal-organic frameworks, two-dimensional zeolites, MXenes, and graphitic carbon nitrides in biohydrogen purification has been presented. The review also provides, in brief, the mechanism and process variables governing biohydrogen purification. Finally, the write-up scrutinizes the challenges faced during the synthesis of two-dimensional advanced materials and also their hydrogen purification performance. © 2026 Elsevier Inc. All rights reserved.Item Energy Densification of Biomass-Derived Furfurals to Furanic Biofuels by Catalytic Hydrogenation and Hydrodeoxygenation Reactions(Multidisciplinary Digital Publishing Institute (MDPI), 2021) Vinod, N.; Dutta, S.The concomitant hydrolysis and dehydration of biomass-derived cellulose and hemicellulose to furfural (FUR) and 5-(hydroxymethyl)furfural (HMF) under acid catalysis allows a dramatic reduction in the oxygen content of the parent sugar molecules with a 100% carbon economy. However, most applications of FUR or HMF necessitate synthetic modifications. Catalytic hydrogenation and hydrogenolysis have been recognized as efficient strategies for the selective deoxygenation and energy densification of biomass-derived furfurals generating water as the sole byproduct. Efficient and eco-friendly catalysts have been developed for the selective hydrogenation of furfurals affording renewable furanic compounds such as 2-methylfuran, 2,5-dimethylfuran and 2-methyltetrahydrofuran with potential applications as biofuel, solvent and chemical feedstock. Hydrogen gas or hydrogen donor molecules, required for the above processes, can also be renewably obtained from biomass using catalytic processes, enabling a circular economy. In this review, the recent developments in the energy densification of furfurals to furanic compounds of commercial significance are elaborated, emphasizing the role of catalyst and the reaction parameters employed. Critical discussion on sourcing hydrogen gas required for the processes, using hydrogen donor solvents, catalyst design and the potential markets of furanic intermediates have been made. Critical evaluations of the accomplishments and challenges in this field are also provided. © 2021 by the authors.Item Synthesis, chemical characterization of novel 1,3-dimethyl acridones as cytotoxic agents, and their DNA-binding studies(2010) Sathish, N.K.; Gopkumar, P.; Rajendra Prasad, V.V.S.; Shanta Kumar, S.M.; Mayur, Y.C.A series of new 1,3-dimethyl acridone derivatives were synthesized with different alkyl side chain (propyl and butyl) substitution at N 10-position and highly basic amine groups at terminal end of alkyl side chain. All the synthesized molecules were screened for their cytotoxic activity against human breast adenocarcinoma (MCF-7) and human promyelocytic leukemia (HL-60) cell lines. DNA binding constants (Ki) of selected compounds were determined with calf-thymus DNA. Results showed that the molecules 7, 8, 10, 11, 12, 13, 14, and 15 exhibited good cytotoxic activity with IC50 value <10 ?M. Compound 14 having (?- hydroxyethyl) piperazine butyl side chain exhibited potent cytotoxic activity against MCF-7 cell line and DNA-intercalating properties. Examination of the relationship between lipophilicity and acridone derivatives showed poor correlation. © Birkhäuser Boston 2009.Item Effective oxidation of alcohols by Iron(III)-Schiff base-triphenylphosphine complexes(2010) Rani, S.; Badekai Ramachandra, B.Iron(III)-Schiff base-triphenylphosphine complexes catalyze the oxidation of alcohols to their corresponding carbonyl compounds in presence of hydrogen peroxide in good yields. © 2010 Elsevier Ltd. All rights reserved.Item Synthesis of worm-shaped carbon nanofibers over a sodium chloride support(2012) Ravindra, R.; Badekai Ramachandra, B.R.Worm-shaped carbon nanofibers (WCNFs) were synthesized in bulk by chemical vapour deposition at 680 °C using iron carboxylate as catalyst precursors and sodium chloride as catalyst support. The products were characterized by scanning electron microscopy, transmission electron microscopy, Raman spectroscopy and X-ray diffraction method. The purity of the purified products was determined by thermal analysis. TheWCNFyield was 6700% relative to catalyst. The simplicity, environmental friendliness and use of easily available low-cost precursors are the advantage of this synthesis technique. © Springer Science+Business Media B.V. 2012.Item Solar photocatalysis for treatment of Acid Yellow-17 (AY-17) dye contaminated water using Ag@TiO2 core-shell structured nanoparticles(2013) Khanna, A.; Shetty K, K.Wastewater released from textile industries causes water pollution, and it needs to be treated before discharge to the environment by cost effective technologies. Solar photocatalysis is a promising technology for the treatment of dye wastewater. The Ag@TiO2 nanoparticles comprising of Ag core and TiO2 shell (Ag@TiO2) have unique photocatalytic property of inhibition of electron-hole recombination and visible light absorption, which makes it a promising photocatalyst for use in solar photocatalysis and with higher photocatalytic rate. Therefore, in the present work, the Ag@TiO2 nanoparticles synthesized by one pot method with postcalcination step has been used for the degradation of Acid Yellow-17 (AY-17) dye under solar light irradiation. The Ag@TiO2 nanoparticles were characterized using thermogravimetric-differential thermal analysis, X-ray diffraction, transmission electron microscopy, selected area electron diffraction, and energy dispersive X-ray analysis. The catalyst has been found to be very effective in solar photocatalysis of AY-17, as compared to other catalysts. The effects of pH, catalyst loading, initial dye concentration, and oxidants on photocatalysis were also studied. The optimized parameters for degradation of AY-17 using Ag@TiO2 were found to be pH 3, dye/catalyst ratio of 1:10 (g/g), and 2 g/L of (NH4)2S2O8 as oxidant. Efficient decolorization and mineralization of AY-17 was achieved. The kinetics of color, total organic carbon, and chemical oxygen demand removal followed the Langmuir-Hinshelwood model. Ag@TiO2 catalyst can be reused thrice without much decline in efficiency. The catalyst exhibited its potential as economic photocatalyst for treatment of dye wastewater. © 2013 Springer-Verlag Berlin Heidelberg.Item Solar light induced photocatalytic degradation of Reactive Blue 220 (RB-220) dye with highly efficient Ag@TiO2 core-shell nanoparticles: A comparison with UV photocatalysis(2014) Khanna, A.; Shetty K, K.Ag core-TiO2 shell (Ag@TiO2) structured nanoparticles with Ag to TiO2 molar ratio of 1:1.7 were synthesized using one pot synthesis method and post calcination was carried out at 450°C for 3h to convert it from amorphous to crystalline form. The Ag core and TiO2 shell formation was confirmed by TEM and AFM. The particle size analysis revealed the average size of Ag@TiO2 as approximately around 30nm. EDS spectra showed the presence of O, Ag, and Ti elements. The improvement in optical properties was proved by DRS which showed significant red shift by Ag core in visible region. Ag@TiO2 exhibited better photocatalytic activity as compared to Degussa P25-TiO2, synthesized TiO2, and the Ag doped TiO2 photocatalysts under UV and solar light irradiation for degradation of Reactive Blue 220 (RB-220) dye. Higher rate of photocatalysis of RB-220 with Ag@TiO2 was obtained under solar light irradiation as compared to UV light irradiation, confirming the capability of the catalyst to absorb both UV and visible light. The kinetics of degradation of dye was found to follow modified Langmuir Hinshelwood (L-H) kinetic model. Ag@TiO2 can be recycled without much decline in the efficacy. Ag@TiO2 has been found to be the effective photocatalyst for degradation of water contaminated with azo dyes under both UV and solar light irradiations. © 2013 Elsevier Ltd.Item Palladium complex in a room temperature ionic liquid: A convenient recyclable reagent for catalytic oxidation(Taylor and Francis Ltd., 2014) Dileep, R.; Badekai Ramachandra, B.; Suresha Kumara, T.H.S.Palladium (Pd)-catalyzed carbonylation of alcohols proceeds in ionic liquid (IL) media (1-ethyl-3-methylimidazolium hexafluorophosphate). Carbonylation of primary/secondary alcohols to aldehydes/ketones was greatly accelerated by the use of a Pd-based catalyst in the presence of NaOCl as an oxidant. The catalyst was more easier to recycle in the IL [Emim]PF6 with an equal-proportioned CH2Cl2 than in the single CH2Cl2 or IL. © 2014 The Author(s). Published by Taylor & Francis.Item Nickel hydroxide/cobalt-ferrite magnetic nanocatalyst for alcohol oxidation(American Chemical Society service@acs.org, 2014) Bhat, P.B.; Inam, F.; Badekai Ramachandra, B.R.A magnetically separable, active nickel hydroxide (Brønsted base) coated nanocobalt ferrite catalyst has been developed for oxidation of alcohols. High surface area was achieved by tuning the particle size with surfactant. The surface area of 120.94 m2 g-1 has been achieved for the coated nanocobalt ferrite. Improved catalytic activity and selectivity were obtained by synergistic effect of transition metal hydroxide (basic hydroxide) on nanocobalt ferrite. The nanocatalyst oxidizes primary and secondary alcohols efficiently (87%) to corresponding carbonyls in good yields. © 2014 American Chemical Society.Item Efficacy of titanium doped-indium tin oxide (Ti/TiO2-ITO) films in rapid oxygen generation under photocatalysis and their suitability for bio-medical application(2014) Subrahmanyam, A.; Ananthakrishnan, A.; Rakibuddin, M.; Paul Ramesh, T.; Raveendra Kiran, M.R.; Shankari, D.; Chandrasekhar, K.The present work describes in detail the photocatalytic properties of controlled titanium doped indium tin oxide (Ti/TiO2-ITO) composite thin films prepared by DC magnetron sputtering and their applicability to developing a bio-medical lung assistive device. The catalytic films of various thicknesses (namely, C1, C2, C3 and C4) were characterized using surface imaging (SEM), X-ray analyses (XRD and EDX), and Raman studies. The optical band gaps of the prepared films are ?3.72-3.77 eV. Photocatalytic efficiencies of the film catalysts were investigated with the aid of a model organic molecule (Rhodamine B dye). The overall photodegradation capacity of the films was found to be slow kinetically, and the catalyst C1 was identified as having a better degradation efficiency (RhB 5 ppm, at pH 6.5) over 5 h under irradiation at 254 nm. The distinctive features of these composite films lie in their oxygen accumulation capacity and unique electron-hole pair separation ability. Investigations on oxygen species revealed the formation of superoxide radicals in aqueous systems (pH 6.5). The prepared films have TiO2 in the anatase phase in the surfaces, and possess the desired photocatalytic efficiency, compatibility to the heme system (are not involved in harmful hydroxyl radical production), and appreciable reusability. Especially, the thin films have a significant ability for mobilization of oxygen rapidly and continuously in aqueous medium under the irradiation conditions. Hence, these films may be a suitable choice for the photo-aided lung assistive design under development. © the Partner Organisations 2014.