Sangaraju Shanmugam

Daegu Gyeongbuk Institute of Science and Technology | DGIST · Department of Energy Science and Engineering

Electrochemical oxygen evolution (OER) and reduction (ORR) reactions have received the great attention due to their importance in several key technologies such as fuel cells, electrolysers and metal-air batteries. Here, we present a simple approach to the preparation of cobalt sulfide nanoparticles in-situ grown on a nitrogen and sulfur co-doped gr...

Polymer electrolyte fuel cells operating at elevated temperature and low relative humidity (RH) have been investigated by utilizing a polyoxometalate coupled graphene oxide–Nafion membrane. A phosphotungstic acid (PW) coupled graphene oxide–Nafion (Nafion/PW-mGO) membrane showed enhanced proton conductivity compared with pristine and recast Nafion...

A recent approach for solar-to-hydrogen generation has been water electrolysis using efficient, stable, and inexpensive bifunctional electrocatalysts within strong electrolytes. Herein, we describe the direct growth of one-dimensional (1D) NiCo2S4 nanowire arrays on a three-dimensional (3D) Ni foam (NiCo2S4 NW/NF). This NiCo2S4 NW/NF array function...

A catalyst for the electrochemical oxidation of methanol in direct methanol fuel cells (DMFCs) comprising Pt8Ti intermetallic nanoparticles dispersed in carbon nanorods (Pt8Ti-TiO2/C) is presented. The catalyst consists of Pt8Ti and rutile TiO2 nanoparticles dispersed in nitrogen-doped carbon hierarchical nanostructures. The Pt8Ti-TiO2/C catalyst s...

The synthesis of electrocatalysts which used simultaneously as electrodes for the hydrazine oxidation reaction (HzOR), and hydrogen evolution reaction (HER) can significantly improve the efficiency of hydrogen production in the water splitting process. Here, Ni–Co–Fe–P binder-free nanosheets were fabricated using the electrochemical deposition meth...

Transition metals have been recognized as excellent and efficient catalysts for transforming gaseous molecules into value-added chemicals. Electrochemical ammonia synthesis through the atmospheric reduction of nitrogen and nitrogen oxide is a promising method for sustainable fertilizer and carbon-free hydrogen energy carriers. However, it is a grea...

Zinc-bromine redox flow batteries (Zn/Br2 RFBs) are gaining attention as a next-generation energy storage system with the advantages of a cost-effective redox couple material price, high output, and high energy density. However, bromine (Br2) crossover through a commercial porous membrane causes self-discharge to lower the capacity retention. Nafio...

Deep eutectic solvents (DES) based on different urea derivatives have been demonstrated to be efficient green alternatives for the ionothermal synthesis of the prototypical Mg-MOF-74 with a strong impact on the morphology and sorption properties of the material. While the synthesis of the material is rather straightforward in the ChCl:urea (1:2) re...

Transition metals have been recognized as excellent and efficient catalysts for the electrochemical nitric oxide reduction reaction (NORR) to value‐added chemicals. In this work, a class of core–shell electrocatalysts that utilize nickel nanoparticles in the core and nitrogen‐doped porous carbon architecture in the shell (Ni@NC) for the efficient e...

The electrochemical oxidation of urea and hydrazine over self-supported Fe-doped Ni3S2/NF (Fe–Ni3S2/NF) nanostructured material is presented. Among the various reaction conditions Fe–Ni3S2/NF-2 prepared at 160 °C for 8 h using 0.03 mM Fe(NO3)3 shows the best results for the hydrazine and urea oxidation reactions. The potential values of 0.36, 1.39,...

Transition metal selenide materials are extensively investigated as electrocatalysts for the hydrogen evolution reaction (HER). Despite having good electrical transportability, they suffer from low abundance catalytic active sites and relatively poor long-term stability. Herein, we demonstrate phosphorous doping in NiSe as an effective strategy to...

Nafion, a perfluorosulfonic acid (PFSA) polymer, is a vital electrolyte that extensively contributes to the commercialization of polymer electrolyte fuel cells (PEFCs). However, adopting Nafion in high-temperature (HT) PEFCs (HT-PEFCs) is still a great challenge. Herein, we present a potential additive (carbon nitride-gadolinium zirconium oxide (gC...

Metallic Ni nanoparticles wrapped with an N-doped carbon shell as a stable catalyst for the electrochemical reduction of NO to NH 3 with high efficiency is described.

Discovering a high performance, durable, and cost-effective oxygen reduction reaction (ORR) electrocatalyst is a key strategy for widespread use of the high efficiency and environmentally friendly fuel cell and metal-air battery technologies. Herein, we fabricate a high performance and durable metal free N and S dual-doped mesoporous carbon nanostr...

A zwitterionic SiO2 composite membrane (PFSA/Z-SiO2) was designed and fabricated for Zinc/Bromine flowless battery (ZBFLB) The composite membrane exhibits low Br2 crossover and high ionic conductivity. The optimized ZBFLB cell...

Electrochemical ammonia synthesis through the atmospheric nitrogen reduction reaction (NRR) is a promising method for sustainable fertilizer and carbon-free hydrogen energy carriers. The inevitable selectivity gap against hydrogen evolution reaction and inert nitrogen (N2) hinders the device-level usage of nitrogen cathodes. In this work, we report...

The development of high-performance, low-cost and durable membrane electrode assembly (MEA) materials receives significant attention from the fuel cell community. A promising MEA design approach introduces a radical scavenging Ti2Zr2O8 nanotubes additive (TZONT) in the polymer electrolyte membrane and cathode catalyst layer for fuel cells operating...

A block copolymer composite membrane of sulfonated poly(arylene ether sulfone ketone) (SPESK) decorated with porous hygroscopic titanium oxide nanotubes (TNT) is designed and fabricated for low relative humidity (RH) operating polymer electrolyte fuel cells (PEFCs). The SPESK-TNT composite membrane in a PEFC operated at 100% RH, and 80 °C resulted...

The emergence of high-performance noble metal-free electrodes in water splitting operations to produce hydrogen is of paramount importance to generate new energy in the future. The oxygen evolution reaction (OER) in water splitting is a slow reaction that consumes much energy to produce hydrogen, and generally, replacing an anodic reaction with les...

Li-O2 batteries are attracting considerable attention as a promising power source for electric vehicles as they have the highest theoretical energy density among reported rechargeable batteries. However, the low energy density and efficiency of Li–O2 batteries still act as limiting factors in real cell implementations. This study proposes the catho...

In proton exchange membrane fuel cells (PEMFCs), polymeric ionomer functions, as the membrane that transports protons and water from one electrode to another and as the catalyst binder and transport channel within the catalyst layer responsible for the electrochemical activity. Here, advanced membrane electrode assemblies (MEAs) of a hierarchical d...

Designing an ion-selective membrane that can deliver high capacity, high cycling efficiency, and low self-discharge rate is imperative for developing a cobalt–tungsten all-heteropolyacid redox-flow battery (H6[CoW12O40] RFB). Herein, for the first-time, a potential composite membrane of Nafion decorated with single-phase TiZrO4 nanotubes (Nafion/Ti...

One material dominating the polymer electrolyte membrane (PEM) technologies is the Nafion membrane due to its excellent properties in ion conduction and chemical stability. That notwithstanding, its reduced performance under low humidity and rapid degradation limit its wide application. Here, a scalable and straightforward method is reported to for...

Electrochemical ammonia synthesis by N2 fixation has proven to be a promising alternative to the energy-consuming, befouling Haber-Bosch process. Considering the low faradaic efficiency and sluggish kinetics of Nitrogen Reduction Reaction (NRR), it is significant to design a robust and selective catalyst. Herein, we demonstrate a single step in-sit...

Development and fabrication of electrodes with favorable electrocatalytic activity, low-cost, and excellent electrocatalytic durability are one of the most important issues in the hydrogen production area using the electrochemical water splitting process. We use the pulse electrodeposition method as a versatile and cost-effective approach to synthe...

Nitrogen (N)-doped carbon is widely used as an anode material for Li-ion battery (LIB). However, the identification of a specific type of N-configuration responsible for Li-ion storage in N-doped carbon is an elusive topic for LIB. Herein, the N-doped porous carbon nanofibers (N-pCNFs) with various atomic percentages of N and different types of N-c...

Metal oxynitrides have been considered recently as emerging electrode materials for supercapacitors. Herein, we converted titanate nanotubes into a series of titanium oxynitride (TiON) nanorods at nitridation temperatures of 800, 900, and 1000 °C in ammonia gas and tested them as supercapacitor electrodes. TiON-800, TiON-900, and TiON-1000 showed c...

Lithium-ion hybrid capacitors (LICs) take the advantage of simultaneous high energy – power output, and become increasingly important for next generation applications. Developing a high performing LICs with high energy-power-cycle combination remains a significant challenge due to low capacity intercalation electrodes, and kinetically sluggish allo...

Herein, the effect of various treatments subjected to FAU zeolites to introduce mesoporosity has been examined on their efficiency as catalyst in the cyclisation of O-aryl 3-arylpropynoic acid ester to its corresponding coumarin. The addition of bio-sourced lignin residues in the alkaline desilication treatment induced the generation of supplementa...

Development of affordable electrocatalysts for both oxygen reduction and evolution reactions (ORR/OER) has received great interest due to their importance in metal-air batteries and regenerative fuel cells. We develop the high-performance bifunctional oxygen electrocatalyst based on Pd nanoparticles supported on cobalt hydroxide nanoplatelets (Pd/C...

A thin Nafion-Neodymium zirconium oxide nanotube (NdZr) composite (Nafion-NdZr) membrane has been fabricated and further modified by the polycation poly (diallyldimethylammonium chloride) (PDDA) and polyanion, poly (sodium styrene sulfonate) (PSS). The ion-selectivity of Nafion-NdZr (1%)/[P-S]2 composite layer membrane was found to be 6.9, 3.5, and...

The major technical obstacles in commercialization of microbial fuel cell technology are the sluggish kinetic, high cost, and poor durability of an air cathode electrocatalyst. This research aimed to synthesize the highly active, stable and low cost non-precious metal catalyst to replace the expensive Pt electrocatalyst using a simple, low cost and...

Most reported catalysts for water oxidation undergo in-situ electrochemical tuning to form the active species for their oxygen evolution reaction (OER). In general, the in-situ electrochemical transformations of non-oxide catalysts are faster than those of corresponding oxides, and they typically display improved OER activity. Although many approac...

We describe the fabrication of hierarchical oxygen and nitrogen enriched-carbon electrode materials from zein and polyacrylonitrile by a simple electrospinning technique for durable and high rate all-vanadium redox flow batteries (VRBs). The nitrogen-doped carbon nanorods (NCNR) provide abundant oxygen-rich and nitrogen active sites, and thereby, e...

Herein, NiCo2S4 supported on sulfur-doped carbon with multi-porous nanostructures are developed to achieve excellent bifunctional catalytic activities. We present a comprehensive study on the composite effect between NiCo2S4 and sulfur-doped carbon as a bifunctional catalyst for oxygen reduction reaction and oxygen evolution reactions. Further, the...

A proton exchange membrane fuel cell uses perfluorosulfonic acid polymers as a proton exchange membrane but exhibits poor performance and durability under dry operating condition. Herein, we develop a composite membrane by incorporating porous inorganic filler, Zr2Gd2O7 into a perfluorosulfonic acid, Nafion. Zr2Gd2O7 nanorods (ZrGdNR) are synthesiz...

The development of a bi-functional active and stable catalyst for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) is an essential challenge in electrochemical overall water splitting. In this study, firstly, NNCs (NNCs) were formed using electrochemical deposition, and then Ni-Co-Fe based mixed sulfide ultrathin nanosheet...

Highly efficient, cost effective and stable non-noble metal electrocatalyst are desirable for cathodic hydrogen evolution reaction. Herein, crystal defects were created in MoS2 with the substitution of P atoms in order to catalyse Hydrogen Evolution Reaction effectively. Performance of MoS2 in electrocatalytic Hydrogen Evolution Reaction is poor in...

Development of new electrocatalysts with high electrocatalytic activity and stability is of great importance in the production of hydrogen fuel. Numerous methods have been established to increase the activity of electrocatalysts, including increasing active surface area and improving intrinsic catalytic activity. However, the electrochemical water...

The prospect of promoting new electrode materials to substitute noble metal electrocatalysts appears to be a boundless challenge. Hence, identifying appropriate materials with enhanced structural and fascinating morphological properties that can compete with the electrocatalytic properties of noble electrocatalysts is necessary. Herein, we report t...

In water splitting, oxygen evolution reaction (OER) requires most active and stable electrocatalysts to overcome their sluggish kinetics thereby improving the device efficiency. In this research work, we developed nanocarbon protected cobalt sulfide, selenide and telluride (core-shell Co 9 S 8 @NC, [email protected] and [email protected]) using sol...

Designing earth-abundant, cost-effective catalysts with superior performance for electrochemical water splitting is among the essential global challenges. In this study, amorphous Ni-Co-P coatings are applied on nickel nanocones array using the cyclic voltammetry electrodeposition method in different cycles and nickel-to-cobalt ratios. The electroc...

Sulfonated silica, synthesized by using tetraethyl orthosilicate and chlorosulfuric acid through calcination, was used as a filler to create Nafion-SSA composite membranes for applying proton exchange membrane fuel cells under low relative humidity (RH)condition. High water uptake and ion exchange capacity values were observed, and the Nafion-SSA c...

We discuss multiple advantages of nanocarbon and their composite materials in metal–air batteries and alkaline water electrolyzer due to their unique properties and structural integrity. In energy devices, the nanocarbon-based electrocatalysts play a significant role to decide the cell efficiency and their stability. As compared with nanocarbon, th...

We describe a facile and simple solid-state thermolysis route for the preparation of Co, Ni, and Fe phosphide nanoparticles embedded in amorphous carbon using an organometallic complex. This was achieved by using a suitable organometallic complex in a single step synthetic route without using any solvent or catalyst. The advantage of using such pre...

Designing efficient and cost-effective electrocatalyst is a great challenge for oxygen reduction and evolution reaction (ORR/OER). Herein, we describe the fabrication of Co and N co-doped porous carbon-based catalysts (CoNPCs) by using a simple organic precursor in a single step method is presented. The CoNPCs show good electrocatalytic activity an...

Herein, an alternative sulfonated poly(arylene ether ketone) (SPAEK)-cerium zirconium oxide nanotube (Ce2Zr2O7NT) composite (SPAEK/Ce2Zr2O7) membrane has been proposed as a potential polymer electrolyte membrane for all vanadium redox flow batteries (VRFBs) performance. The as-prepared composite membrane showed higher ion selectivity and reduced va...

Pulse electrodeposition of Pt and Sn using 10 mM H2PtCl6⋅6H2O in 0.10 M H2SO4 and 10 mM SnCl2⋅2H2O in 0.10 M HCl was conducted on a support matrix consisting of electropolymerized poly (3,4-ethylenedioxythiophene) (PEDOT) and electrochemically exfoliated graphene oxide (EGO). The Field Emission – Scanning Electron Microscopy (FE-SEM) studies of PtS...

A unique three-dimensional (3D) structure consisting of a hierarchical nickel–cobalt dichalcogenide spinel nanostructure is investigated for its electrocatalytic properties at benign neutral and alkaline pH and applied as an air cathode for practical zinc–air batteries. The results show a high oxygen evolution reaction catalytic activity of nickel–...

We describe the fabrication of a new block copolymer, sulfonated poly(ether ketone sulfone) (SPEKS) decorated with sulfonated graphene oxide (sGO) as a potential proton exchange composite membrane for all vanadium redox flow batteries (VRB). The simple design of SPEKS/sGO composite membrane offers key advantages in VRB relative to the commercial Na...

A family of Al-rich ZSM-5 zeolites with Si / Al = 8 ± 0.5 was prepared according to a biomass-mediated supramolecular approach. A combination of advanced characterisation techniques and periodic density functional theory (DFT) calculations unraveled the purity and stability of un-expected Al-enriched ZSM-5 structures, hence allowing to cross the fr...

In article 1702838 by Sangaraju Shanmugam and co‐workers, a Prussian blue analogue‐derived metalrich, thin graphitic nitrogen doped‐carbon (NC) layer, core‐shell Co@NC catalyst overcomes the sluggish OER kinetics of overall alkaline water splitting. The continuous operation of water splitting over several hundred hours using Co@NC is demonstrated,...

Functionalizing nanostructured carbon nanofibers (CNFs) with bimetallic phosphides enables the material to become an active electrode for multifunctional applications. A facile electrospinning technique is utilized for the first time to develop NiCoP nanoparticles encapsulated CNFs that are used as an energy storage system of supercapattery, and as...

Composites of transition metal/metal‐alloy with graphitic carbon layer have received considerable attention as non‐precious catalysts for the eco‐friendly energy devices. In this work, we report graphitic carbon supported NiCo‐alloy (NiCo@GC) as non‐precious electrocatalysts for the oxygen reduction reaction in alkaline condition. The effect of pyr...

The oxygen electrode plays a vital role in the successful commercialization of renewable energy technologies, such as fuel cells and water electrolyzers. In this study, the Prussian blue analogue-derived nitrogen-doped nanocarbon (NC) layer-trapped, cobalt-rich, core–shell nanostructured electrocatalysts (core–shell Co@NC) are reported. The electro...

A unique multifunctional electrode made of well-defined highly crystalline Ni–P nanoparticles interweaved apiece to form sponge-like structure prepared by the single-step hydrothermal method. The distinct phases of interlinked nanospherical Ni–P compounds (Ni2P, Ni2P/Ni12P5, and Ni12P5) were obtained at 140 °C with different reaction time periods....

The development of efficient catalysts to overcome the significant overpotential of oxygen evolution reaction (OER) is the key bottleneck in the large-scale production of pure hydrogen. In the present work, we describe a simple approach for the fabrication of CoS2-TiO2 hybrid catalysts by the heat treatment of a cobalt thiourea complex in the prese...

The oxygen electrode plays a vital role in the successful commercialization of renewable energy technologies, such as fuel cells and water electrolyzers. Here, we report the Prussian blue analogue-derived nitrogen-doped, nanocarbon layer-trapped, cobalt-rich, core-shell nanostructured electrocatalysts (core-shell Co@NC). Our electrode exhibits an i...

The sulfonated poly(arylene ether) (SPAE) multiblock copolymers composed of densely sulfonated hydrophilic blocks were designed and fabricated through aromatic nucleophilic substitution reaction. The modified SPAE (mSPAE) membrane showed a well phase separated morphology as revealed by transmission electron microscopy (TEM) studies. The dense sulfo...

Conducting and electroactive fabrics suitable for supercapacitor electrodes were successfully prepared by combining carbon nanotubes (CNT) and polyaniline (PANi) with pineapple-polyester blended woven fabrics (PPWF) via dip-and-dry process and in situ chemical polymerization. The conductivity and capacitive behavior were studied using four-point pr...

The development of efficient and durable non-precious cathode catalyst have been received the great interest to replace the commercial noble catalysts, thereby minimizing the overall cost of polymer electrolyte membrane fuel cells. We describe the synthesis of self-redox CeO2 supported Co in nitrogen-doped carbon nanorods (Co-CeO2/N-CNR) by the ele...

The organic-inorganic nanocomposites were synthesized by sol-gel techniques. The constructed film renders photochromism, which can be tuned by choosing suitable polyoxometalates (POM). The molybdenum POMs show better photochromism than the tungsten POMs, which is well correlated with the first reduction potentials and band gap of the POM.

A phosphotungstic acid (PW) decorated graphene oxide (GO) is explored as a filler for sulfonated poly(arylene ether ketone) (SPAEK) block copolymer. The SPAEK/PW-mGO composite membrane shows higher proton conductivity than a pristine SPAEK membrane. At 80 °C under 25% relative humidity (RH) condition, the fuel cell configured with the SPAEK/PW-mGO...

An ultra-high ion-selective membrane composed of aromatic block copolymer sulfonated poly(arylene ether ketone) (SPAEK) and ZrO2 nanotube (ZrNT) is designed and fabricated via a solution-casting method. The composite membrane showed high proton conductivity and reduced VO2+ crossover rate compared with a pristine SPAEK membrane. The high proton con...

Chrysanthemum flower like NiCo2O4-Nitrogen doped graphene oxide composite material has been explored as the bifunctional cathode electrocatalyst for aqueous zinc-air and non-aqueous lithium-oxygen batteries. This cathode exhibits the maximum discharge capacity of 712 and 15046 mAhg-1 for zinc-air and lithium-oxygen batteries, respectively with a st...

A bifunctional air cathode for the electrochemical oxygen reduction and evolution in a Li-O2 battery comprising Co-CoO nanoparticles embedded in the nitrogen-doped carbon nanorods (Co-CoO/N-CNR) is presented. The nanorod morphology with mesoporous nanostructures can handle continuous formation and decomposition of Li2O2 and favors the transport of...

One of the important challenges in alkaline water electrolysis are to utilize a bifunctional catalyst for both hydrogen evolution (HER) and oxygen evolution (OER) reactions to increase the efficiency of water splitting devices for the long durable operations. Herein, nickel-cobalt-titanium alloy directly grown on a high corrosion resistance titaniu...

In this communication, we present a new synthesis method for the fabrication of hybrid metal-Cu2S (M = Pt, FePt) nanocrystals (HNs). The metal-Cu2S HNs were investigated in photocatalytic hydrogen generation as effective co-catalysts on TiO2. The Pt-Cu2S/TiO2 catalyst showed a higher hydrogen generation rate compared with a pure TiO2 catalyst. This...

A cost-effective dual heteroatoms doped three-dimensional carbon nanofoam wrapped iron mono-sulfide (FeS) nanoparticles (nps), FeS-C acts as an efficient bi-functional catalyst for Lithium oxygen (Li-O2) battery application. The Li-O2 battery study shows this cathode exhibits a maximum deep discharge capacity of 14,777.5 mAhg-1 with a 98.1% columbi...

A high ion-selective membrane for vanadium flow battery (VRB) consisting of sulfonated poly(arylene ether ketone) (SPAEK) and polyoxometalate coupled with a graphene oxide was designed and fabricated. The SPAEK/PW-mGO composite membrane showed effective low self-discharge rate and excellent coulombic efficiency (98.73%) in VRB.

In this article, we report the pre-screening of anti-cancer effect of Calotropis procera against glioblastoma cell lines (LN-18) by means of electrochemical methods. Soxhlet assisted extraction (SAE) has been employed to extract the polyphenol contents present in the leaf of Calotropis procera. The phytochemical analysis of the extract has been stu...

A high-performance composite membrane for vanadium redox flow battery (VRB) consisting of ZrO2 nanotubes (ZrNT) and perfluorosulfonic acid (Nafion) was fabricated. The VRB operated with a composite (Nafion-ZrNT) membrane showed the improved ion-selectivity (ratio of proton conductivity to permeability), low self-discharge rate, high discharge capac...

A catalyst consisting of palladium – nickel supported on exfoliated graphene oxide (PdNi/EGO) composite was synthesized. The catalytic activity was tested for ethanol oxidation reaction (EOR) in half-cell using cyclic voltammetry (CV) and subsequently it was used as an anode material in a direct ethanol fuel cell (DEFC). Transmission Electron Micro...