Research - Ponnurangam Lab

Vanadium (for redox flow batteries), lithium (in batteries), and rare earth elements (REE, for the high-tech sector) are strategic/critical metals. The extraction and selective separation of these valuable elements from low-grade ore bodies (shale) and ultra-dilute secondary resources (blast furnace slag, vacuum residue, tailings, petcoke, and formation water) remains an unresolved challenge. The state-of-art technology for the release of these metals from their matrices involves some form of chemical roasting at high temperatures (typically 800+°C), which is an energy and material-intensive approach and requires high capital investments. Our research explores the suitability of the efficient leaching of metal ions from different feedstocks through optimization of the energy-expensive roasting step as well as selectively purifying metal ions from other gangue ions. We have developed alternative greener methods for purifying valuable metals from leachates. One such approach is based on utilizing a bio-based and cheap adsorbent (functionalized cellulose). Through this approach, we have achieved high selectivity for vanadium and rare earth elements over nickel, copper, chromium, and iron in the lab. We have also demonstrated the use of greener reagents such as monorhamnolipids for selective ion flotation of REEs as opposed to commonly found gangue ions. Currently, we are developing polymer nanocomposites that can selectively enrich lithium ions present in dilute concentrations (~75 ppm) in formation waters as opposed to other alkali and alkaline earth metal ions present in very high concentrations.

Capacitive deionization (CDI) has emerged as a promising new technology for the production of clean water from brackish or even seawater at high efficiency and at low cost, also showing promise in storing energy while simultaneously achieving desalination. Our group is developing electrochemically-based methods for water desalination and recovery of valuable elements. In collaboration with Profs. Birss and Chernyshova, we have developed metal-free recyclable electrosorbents and capacitive electrodes based on conducting polymers and nanocarbon. The performance of these electrodes is better than their carbon analogs. Also, the electrochemical suite of technologies offers benign and in situ pathways for eliminating contaminants from a wide variety of polluted soils (including difficult-to-treat fine clays). In our group, an electrokinetic solution in combination with CDI is being developed to treat salt- and hydrocarbon-contaminated soils that are abandoned after oil-field operations. A key advantage of our approach is its non-invasiveness and modularity which results in a significant reduction in soil handling costs as well as an ability to apply to a wider contaminated area.

Advanced battery materials research is geared towards identifying materials and their assemblies that demonstrate energy density higher than that of conventional Li-ion batteries. The energy densities of Li-ion systems are limited by intercalation chemistry at the cathode. Recently, our collaborators in Chemistry department (Dr. Thangadurai’s group) have developed a high energy density system (a novel Li - MoS₃ electrode with discharge capacity of ~ 1000 mAh/g). Using density functional theory simulations (DFT), our group has clarified the mechanisms by which such enhancement occurs. Our ongoing collaboration is focused on, using DFT, screening (1) various layered sulfides to identify their thermodynamic potential window (stability studies) and (2) solid electrolytes based on ternary mixed-oxide and to identify optimal compositions which result in excellent stability under high applied potential (e.g., > 8 V).

Improving transport across ionomer membranes in polymer fuel cells and Li-ion batteries. A theory-based understanding of ionomer aggregation in different solvents as well as ionomer self-assembly in solid-state is crucial for transitioning from the empirically guided fabrication of high-performance electrodes of fuel cells and other electrochemical devices. Considering Nafion as a model ionomer, our collaborative research (Dr. Karan) has reshaped the long-held view of Nafion aggregate structures as elongated cylinder-like aggregates. We have found a variety of structures, along with evidence of the formation of ion-pair clusters. These results have elucidated that aggregation of ionomers, unlike non-ionic macromolecules, expectedly, is dominated by strong electrostatic interactions, and thereby solvent dielectric constant and counter-ion type play crucial roles. Using a similar approach, we have demonstrated differences in the dispersion behavior of nanoparticles in polymer nanocomposites with or without surface functionalization.

Low-Temperature Conversion of CO₂ into Fuels: Electrocatalytic conversion of CO₂ into specialty chemicals or fuels using renewable energy is a very promising approach to reduce our carbon footprint and our dependence on fossil fuels. There are several key challenges that prevent widespread commercialization of this technology. These include (a) low energy efficiency of CO₂ conversion (large overpotentials), (b) poor products selectivity – most common products include a mixture of CO, HCOOH, and H₂, (c) catalyst poisoning, and (d) sluggish kinetics (low current). Towards solving these challenges, we use a combination strategy of bench-scale electrolyzer development, spectroscopic characterization, and DFT-based modeling methods. In particular, to improve the robustness of the electrocatalysts, our group is developing nanocomposite electrodes with (conducting) polymers. Further efforts are ongoing in our group to develop gas-diffusion systems based on these electrodes (adapting a fuel cell configuration through collaboration with Prof. Karan’s group). The spectroscopic characterization and DFT modeling work are geared towards elucidating the role of CO₂ intermediates as well as the effect of applied electric field on electrocatalysis pathways. This is expected to accelerate the discovery of durable and selective CO₂ electroreduction catalysts.

High Temperature Conversion of CO₂ into Fuels: Conversion of CO₂ to syngas can be achieved in solid oxide electrolysis cells at high temperatures (~1000 K) using perovskite-based solid oxides as electrocatalysts. This process is projected to be among the most viable ways of generating fuels from CO₂. Using DFT calculations and reactive molecular dynamics (in-house developed reactive forcefields), we study the electronic structure and stability of perovskite-based solid oxides used as electrocatalysts for CO₂ conversion. The effect of high temperatures and applied electric field is investigated, as well as the time evolution of reactions involving CO₂ on the surface of slabs from the perovskites.

In the above projects, the performance of the complex systems are controlled by the colloid and surface chemistry and physics of complex and (electrified) heterogeneous systems (e.g., catalysts, sorbents, and mineral matrices of different origin). Therefore, to accelerate the technology development, research in our group is focused on a better understanding of this chemistry and physics through combining advanced experimental methods with theoretical modelling. The experimental methods include bench-scale electrochemical and interfacial characterizations, operando spectroscopy, electrochemical microscopy with Kelvin probe, X-ray photoelectron spectroscopy, and NMR. The theoretical modelling methods include quantum chemical (Density Functional Theory, DFT) and classical and reactive molecular simulation methods.

Edited Books and Book Chapters:

Multidisciplinary Advances in Efficient Separation Processes IV Chernyshova, S Ponnurangam, Q Liu American Chemical Society	2020
Selective recovery of critical and toxic elements from their low-concentrated solutions using surface-based electrochemical separation methods I Chernyshova, D Bakuska, S Ponnurangam Multidisciplinary Advances in Efficient Separation Processes, 115-165	2020
Progress in Capacitive Deionization for Desalination of Brackish Water: A Materials Perspective C Ai, S Ponnurangam Multidisciplinary Advances in Efficient Separation Processes, 91-113	2020
Metal Electrodes: CO2 Reduction Interfacial Processes S Ponnurangam, I Chernyshova, P Somasundaran Encyclopedia of Surface and Colloid Science, Third Edition, 4148-4161	2015
Nanoparticles: size dependency and electrochemical properties IV Chernyshova, S Ponnurangam, P Somasundaran Encyclopedia of surface and colloid science. Boca Raton: CRC Press, Taylor …	2015

Journal Publications:

Ultrahigh Sulfur Loading Tolerant Cathode Architecture with Extended Cycle Life for High Energy Density Lithium–Sulfur Batteries AM Abraham, K Thiel, M Shakouri, Q Xiao, A Paterson, J Schwenzel, ... Advanced Energy Materials, 2201494	2022
Performance Characteristics of Polymer Electrolyte Membrane CO2 Electrolyzer: Effect of CO2 Dilution, Flow Rate and Pressure P Karimi, A Alihosseinzadeh, S Ponnurangam, K Karan Journal of The Electrochemical Society	2022
First-principles investigations into the effect of oxygen vacancies on the enhanced reactivity of NiO via Bader charge and density of states analysis NM Rasi, S Ponnurangam, N Mahinpey Catalysis Today	2022
Insight into MgO-supported NiO reactivity from atomic-scale electronegativity for oxygen carrier design and catalyst production applications NM Rasi, A Karcz, S Ponnurangam, N Mahinpey Catalysis Today	2022
A global design principle for polysulfide electrocatalysis in lithium–sulfur batteries—A computational perspective AM Abraham, T Boteju, S Ponnurangam, V Thangadurai Battery Energy, 20220003	2022
Electrochemistry of new generation conformal polyaniline/carbon scaffolds with monodispersed nanopores and high capacitance C Ai, IV Chernyshova, EL Gawron, S Ponnurangam, VI Birss Journal of Materials Chemistry C 10 (6), 2271-2280	2022
Facet-Engineered Tungsten Disulfide for Promoting Polysulfide Electrocatalysis in Lithium–Sulfur Batteries AM Abraham, S Ponnurangam, V Thangadurai Inorganic Chemistry 60 (17), 12883-12892	2021
Promoting Effect of Supports with Oxygen Vacancies as Extrinsic Defects on the Reduction of Iron Oxide JC Mora, YCM Nederstigt, JM Hill, S Ponnurangam The Journal of Physical Chemistry C 125 (26), 14299-14310	2021
Surface functionalization-induced effects on nanoparticle dispersion and associated changes in the thermophysical properties of polymer nanocomposites A Mitra, M Trifkovic, S Ponnurangam Macromolecules 54 (9), 3962-3971	2021
Effects of support and oxygen vacancies on the energetics of NiO reduction with H 2 for the chemical looping combustion (CLC) reaction; a DFT study NM Rasi, AS Hyla, S Ponnurangam, N Mahinpey Physical Chemistry Chemical Physics 23 (22), 12795-12806	2021
Foam flotation of rare earth elements by conventional and green surfactants S Shetty, IV Chernyshova, S Ponnurangam Minerals Engineering 158, 106585	2020
Cytotoxicity, cellular localization and photophysical properties of Re (I) tricarbonyl complexes bound to cysteine and its derivatives MS Capper, A Enriquez Garcia, N Macia, B Lai, JB Lin, M Nomura, ... JBIC Journal of Biological Inorganic Chemistry 25 (5), 759-776	2020
Selective recovery of critical and toxic elements from their low-concentrated solutions using surface-based electrochemical separation methods I Chernyshova, D Bakuska, S Ponnurangam Multidisciplinary Advances in Efficient Separation Processes, 115-165	2020
Progress in Capacitive Deionization for Desalination of Brackish Water: A Materials Perspective C Ai, S Ponnurangam Multidisciplinary Advances in Efficient Separation Processes, 91-113	2020
Multidisciplinary Advances in Efficient Separation Processes IV Chernyshova, S Ponnurangam, Q Liu American Chemical Society	2020
Atomistic md study of nafion dispersions: Role of solvent and counterion in the aggregate structure, ionic clustering, and acid dissociation A Tarokh, K Karan, S Ponnurangam Macromolecules 53 (1), 288-301	2019
Efficient Synthesis and Characterization of Robust MoS₂ and S Cathode for Advanced Li–S Battery: Combined Experimental and Theoretical Studies A Mammoottil Abraham, SP Kammampata, S Ponnurangam, ... ACS applied materials & interfaces 11 (39), 35729-35737	2019
Activation of CO 2 at the electrode–electrolyte interface by a co-adsorbed cation and an electric field IV Chernyshova, S Ponnurangam Physical Chemistry Chemical Physics 21 (17), 8797-8807	2019
Ligand-centered electrochemical processes enable CO 2 reduction with a nickel bis (triazapentadienyl) complex Z Dubrawski, J Heidebrecht, BMP Lombardi, AS Hyla, J Willkomm, ... Sustainable Energy & Fuels 3 (5), 1172-1181	2019
On the origin of the elusive first intermediate of CO2 electroreduction IV Chernyshova, P Somasundaran, S Ponnurangam Proceedings of the National Academy of Sciences 115 (40), E9261-E9270	2018
Nitrogen-containing polymers as a platform for CO2 electroreduction S Ponnurangam, IV Chernyshova, P Somasundaran Advances in colloid and interface science 244, 184-198	2017
Catalytic synthesis of mixed alcohols mediated with nano-MoS2 microemulsions JK Hasty, S Ponnurangam, S Turn, P Somasundaran, T Kim, D Mahajan Fuel 164, 339-346	2016
Robust Electroreduction of CO₂ at a Poly(4‐vinylpyridine)–Copper Electrode S Ponnurangam, CM Yun, IV Chernyshova ChemElectroChem 3 (1), 74-82	2016
Biocompatibility of polysebacic anhydride microparticles with chondrocytes in engineered cartilage S Ponnurangam, GD O’Connell, CT Hung, P Somasundaran Colloids and Surfaces B: Biointerfaces 136, 207-213	2015
Metal Electrodes: CO2 Reduction Interfacial Processes S Ponnurangam, I Chernyshova, P Somasundaran Encyclopedia of Surface and Colloid Science, Third Edition, 4148-4161	2015
Nanoparticles: size dependency and electrochemical properties IV Chernyshova, S Ponnurangam, P Somasundaran Encyclopedia of surface and colloid science. Boca Raton: CRC Press, Taylor …	2015
Beneficial effects of cerium oxide nanoparticles in development of chondrocyte-seeded hydrogel constructs and cellular response to interleukin insults S Ponnurangam, GD O'Connell, IV Chernyshova, K Wood, CTH Hung, ... Tissue Engineering Part A 20 (21-22), 2908-2919	2014
Stabilization of Silicon Carbide (SiC) micro-and nanoparticle dispersions in the presence of concentrated electrolyte A Vilinska, S Ponnurangam, I Chernyshova, P Somasundaran, D Eroglu, ... Journal of colloid and interface science 423, 48-53	2014
Linking interfacial chemistry of CO 2 to surface structures of hydrated metal oxide nanoparticles: Hematite IV Chernyshova, S Ponnurangam, P Somasundaran Physical Chemistry Chemical Physics 15 (18), 6953-6964	2013
Rational design of interfacial properties of ferric (hydr) oxide nanoparticles by adsorption of fatty acids from aqueous solutions S Ponnurangam, IV Chernyshova, P Somasundaran Langmuir 28 (29), 10661-10671	2012
A molecular dynamics study of the interaction of oleate and dodecylammonium chloride surfactants with complex aluminosilicate minerals B Rai, P Sathish, J Tanwar, KS Moon, DW Fuerstenau Journal of Colloid and Interface Science 362 (2), 510-516	2011
Adsorption of fatty acids on iron (hydr) oxides from aqueous solutions IV Chernyshova, S Ponnurangam, P Somasundaran Langmuir 27 (16), 10007-10018	2011
Effect of nanosize on catalytic properties of ferric (hydr) oxides in water: Mechanistic insights IV Chernyshova, S Ponnurangam, P Somasundaran Journal of catalysis 282 (1), 25-34	2011
Tailoring (bio) chemical activity of semiconducting nanoparticles: Critical role of deposition and aggregation IV Chernyshova, S Ponnurangam, P Somasundaran Journal of the American Chemical Society 133 (24), 9536-9544	2011
Effect of coadsorption of electrolyte ions on the stability of inner-sphere complexes S Ponnurangam, IV Chernyshova, P Somasundaran The Journal of Physical Chemistry C 114 (39), 16517-16524	2010
Nanoparticles: characteristics, mechanisms and modulation of biotoxicity P Somasundaran, X Fang, S Ponnurangam, B Li KONA powder and particle journal 28, 38-49	2010
On the origin of an unusual dependence of (bio) chemical reactivity of ferric hydroxides on nanoparticle size IV Chernyshova, S Ponnurangam, P Somasundaran Physical Chemistry Chemical Physics 12 (42), 14045-14056	2010
Fluoride-containing hydraulic cements and methods of making the same B Rai, S Ponnurangam, P Kapur, A Unal, R Cahill, J Norton, J Stenack, ... US Patent App. 11/835,076	2008
Effect of alcohol and polyglycol ether frothers on foam stability, bubble size and coal flotation AK Gupta, PK Banerjee, A Mishra, P Satish International Journal of Mineral Processing 82 (3), 126-137	2007
Molecular dynamic simulations of self-assembled alkylthiolate monolayers on an Au (111) surface B Rai, P Sathish, CP Malhotra, Pradip,*,† and, KG Ayappa Langmuir 20 (8), 3138-3144	2004
Rational design of dispersants for colloidal processing of barium titanate suspensions by molecular modeling PB RAI, P Sathish, S Krishnamurty Ferroelectrics 306 (1), 195-208	2004
Rational design of dispersants by molecular modeling for advanced ceramics processing applications B Rai, P Sathish KONA Powder and Particle Journal 22, 151-158	2004

Research - Ponnurangam Lab

Sustainable Resource Extraction

Advanced Electrochemical Water Treatment and Soil Remediation methods

Screening of battery materials

Molecular Assemblies in Fuel Cell Systems

Electrocatalytic conversion of CO2

Methodology

Publications