Publications by authors named "Ram K Gupta"

Article Synopsis
  • Direct ethanol fuel cells (DEFCs) are promising for portable power, but their economic viability depends on reducing the cost of precious metal catalysts and improving anode performance.
  • Despite advancements in platinum (Pt) nanoengineering, issues remain with the quick loss of electrocatalytic activity due to catalyst poisoning during ethanol oxidation.
  • This review discusses the mechanisms of ethanol oxidation on noble metal anodes and highlights the challenges and opportunities for enhancing electrocatalytic efficiency.
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  • The direct methanol fuel cell (DMFC) is a promising power source for small electronics and vehicles due to its efficiency, low temperatures, and energy density.
  • The methanol oxidation process (MOR) is crucial for the cell's function but faces challenges, including slow reaction rates, high costs from Pt-based catalysts, and CO poisoning.
  • Researchers are actively seeking alternative catalysts, focusing on both noble and non-noble metals, to improve MOR efficiency and reduce costs for better commercialization of DMFCs.
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The growth of graphene on a metal substrate using chemical vapor deposition (CVD), assisted by hydrocarbons such as CH, CH, CH, leads to the formation of carbon clusters, amorphous carbon, or any other structure. These carbon species are considered as unwanted impurities; thus a conventional etching step is used simultaneously with CVD graphene growth to remove them using an etching agent. Meanwhile, art etching is a specific method of producing controlled non-Euclidean and Euclidean geometries by employing intricate and precise etching parameters or integrated growth/etching modes.

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In this work, carbonization and subsequent activation procedures were adopted to synthesize waste shea butter shells into oxygen-rich interconnected porous activated carbon (SAC_x, x is the mass ratio of KOH used for activation). The SAC_1.5 electrode material showed outstanding electrochemical performance with high specific capacitance (286.

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Over the past few decades, polymer composites have received significant interest and become protagonists due to their enhanced properties and wide range of applications. Herein, we examined the impact of filler and flame retardants in hemp seed oil-based rigid polyurethane foam (RPUF) composites' performance. Firstly, the hemp seed oil (HSO) was converted to a corresponding epoxy analog, followed by a ring-opening reaction to synthesize hemp bio-polyols.

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Etching technology - one of the representative modern semiconductor device makers - serves as a broad descriptor for the process of removing material from the surfaces of various materials, whether partially or entirely. Meanwhile, thinning technology represents a novel and highly specialized approach within the realm of etching technology. It indicates the importance of achieving an exceptionally sophisticated and precise removal of material, layer-by-layer, at the nanoscale.

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Article Synopsis
  • Producing polymers from renewable plant oils (POs) like soybean oil can contribute to sustainable development in the materials sector.
  • A unique, eco-friendly resin was created by cross-linking epoxidized soybean oil with branched polyamines, resulting in a strong structural adhesive known as melamine pentane diamine (MPD).
  • When tested, the MPD polymer demonstrated excellent bonding strength, outperforming other resins and metals in various temperature conditions, achieving nearly 2000 kPa in shear strength at 180 °C.
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Bioplastics are one of the answers that can point society toward a sustainable future. Under this premise, the synthesis of polymers with competitive properties using low-cost starting materials is a highly desired factor in the industry. Also, tackling environmental issues such as nonbiodegradable waste generation, high carbon footprint, and consumption of nonrenewable resources are some of the current concerns worldwide.

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Synthesizing polymeric materials that are both sustainable and practical has become a priority. Polyurethanes (PUs) are becoming more popular because of their countless applications and exclusive properties in many sectors. While considering the current issue of environmental problems and the excessive use of petroleum products, nonisocyanate PU (NIPU) are favored due to their sustainability and low toxicity compared to conventional PU.

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Eco-friendly and cost-effective catalysts with multiple active sites, large surface area, high stability and catalytic activity are highly desired for efficient water splitting as a sustainable green energy source. Within this line, a facile synthetic approach based on solventless thermolysis was employed for the simple and tunable synthesis of NiMgFeO (0 ≤ x ≤ 1) nanosheets. The characterization of nanosheets (via p-XRD, EDX, SEM, TEM, HRTEM, and SAED) revealed that the pristine ferrites (NiFeO and MgFeO), and their solid solutions maintain the same cubic symmetry throughout the composition regulation.

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Tuning the electronic properties of transition metals using pyrophosphate (PO) ligand moieties can be a promising approach to improving the electrochemical performance of water electrolyzers and supercapacitors, although such a material's configuration is rarely exposed. Herein, we grow NiPO, CoPO, and FePO nanoparticles on conductive Ni-foam using a hydrothermal procedure. The results indicated that, among all the prepared samples, FePO exhibited outstanding oxygen evolution reaction and hydrogen evolution reaction with the least overpotential of 220 and 241 mV to draw a current density of 10 mA/cm.

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Although porphyry systems like metallo-phthalocynine are recognized as promising molecular models for electrocatalytic oxygen reduction reaction (ORR), their poor durability and methanol tolerance are still challenges and need improvement before being considered for practical applications. Herein, we successfully designed and constructed a Fe-phthalocyanine-derived highly conjugated 2D covalent organic framework (2D FePc-COF), using octa-amino-Fe-phthalocyanine (OA-FePc) and cyclohexanone as precursors. The prepared 2D FePc-COF was characterized via multiple analytic techniques.

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Wastewater treatment is critically important for the existence of life on earth; however, this approach involves the removal of toxic metal contaminants and organic pollutants, requiring efficient adsorbent materials. Within this agenda, metal-organic frameworks (MOFs) appear to be potential materials due to their unique properties as efficient adsorbents, effective photocatalysts, and reliable semi-permeable membranes. Therefore, MOFs have undergone various modifications over the years without desirable success to improve adsorption capacity, hydro-stability, reaction kinetics, and reusability.

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Bacterial transmission is considered one of the potential risks for communicable diseases, requiring promising antibiotics. Traditional drugs possess a limited spectrum of effectiveness, and their frequent administration reduces effectiveness and develops resistivity. In such a situation, we are left with the option of developing novel antibiotics with higher efficiency.

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The major center of attraction in renewable energy technology is the designing of an efficient material for both electrocatalytic and supercapacitor (SC) applications. Herein, we report the simple hydrothermal method to synthesize cobalt-iron-based nanocomposites followed by sulfurization and phosphorization. The crystallinity of nanocomposites has been confirmed using X-ray diffraction, where crystalline nature improves from as-prepared to sulfurized to phosphorized.

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Article Synopsis
  • Gestational diabetes (GDM) and preexisting diabetes increase the risk of pre-eclampsia, which can lead to serious complications for both mothers and babies.
  • The study analyzed 2050 pregnant women, finding that women with GDM or diabetes before pregnancy had higher rates of pre-eclampsia compared to healthy women; socio-economic status and previous pregnancy history significantly influenced these risks.
  • Serum biomarkers like SHBG, IGF-I, and vitamin D levels were not effective predictors of pre-eclampsia, but a risk score model identified some women at higher risk, with an area under the ROC curve of 0.68 suggesting moderate predictive capability.
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MXene is becoming a "rising star" material due to its versatility for a wide portfolio of applications, including electrochemical energy storage devices, electrocatalysis, sensors, biomedical applications, membranes, flexible and wearable devices, etc. As these applications promote increased interest in MXene research, summarizing the latest findings on this family of materials will help inform the scientific community. In this review, we first discuss the rapid evolutionary change in MXenes from the first reported MXT structure to the last reported MXT structure.

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Article Synopsis
  • * MXenes can be easily combined with other materials, like oxides and polymers, enhancing their performance for various applications, particularly in environmental and energy storage uses.
  • * This review focuses on the latest advancements in MXenes for electrochemical energy storage, detailing their synthesis, properties, and applications in supercapacitors and batteries while discussing future research directions.
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  • Researchers developed an eco-friendly nanocomposite of Pd/NiOPdO using plant-based agents to create effective materials for energy storage in supercapacitors.
  • The nanocomposite exhibited a unique mixed phase structure and showed promising electrochemical properties, including a specific capacitance of 88 F/g and low internal resistance of 0.8 Ω.
  • Characterization techniques like XRD, SEM, and XPS confirmed the material's composition and structure, highlighting its potential for improved performance in energy storage applications.
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Currently, polyurethane (PU) manufacturers seek green alternatives for sustainable production. In this work, sunflower oil is studied as a replacement and converted to a reactive form through epoxidation and oxirane opening to produce rigid PU foams. Confirmatory tests such as Fourier-transform infrared spectroscopy (FT-IR), gel permeation chromatography (GPC), and hydroxyl value among others were performed to characterize the synthesized polyol.

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  • The study focuses on creating eco-friendly cobalt oxide nanoparticles using orange peel extract as a reducing agent, addressing the growing need for energy storage and environmental sustainability.
  • Various cobalt precursors were used to compare the phase and electrochemical properties of the nanoparticles, with the phosphide variants showing the highest capacitance at 185 F/g.
  • The research suggests that these phosphide-based nanoparticles retain over 85% capacitance after 5000 cycles, highlighting a promising green method for developing materials for energy applications.
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Article Synopsis
  • Sunflower oil was transformed into a polyol through a two-step process involving epoxidation and ring-opening reactions, and its successful synthesis was confirmed with structural and wet-chemistry analyses.
  • Bio-based polyurethane (BPU) films were created using this polyol and diisocyanate, and the effects of adding graphene oxide (GO) and reduced graphene oxide (rGO) on their properties were investigated.
  • Tests showed that even small additions of GO and rGO significantly enhanced the mechanical and thermal properties of the BPU films, with tensile strength increasing from 22.5 to 26 MPa and storage modulus improving significantly, suggesting they could be valuable in coating applications.
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Supercapacitors may be able to store more energy while maintaining fast charging times; however, they need low-cost and sophisticated electrode materials. Developing innovative and effective carbon-based electrode materials from naturally occurring chemical components is thus critical for supercapacitor development. In this context, biopolymer-derived porous carbon electrode materials for energy storage applications have gained considerable momentum due to their wide accessibility, high porosity, cost-effectiveness, low weight, biodegradability, and environmental friendliness.

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  • The study explores a new solventless method for creating solid solutions of NiCoFeO, which offers an eco-friendly and cost-effective alternative to traditional wet chemical routes used for synthesizing spinel ferrites.
  • Characterization techniques like p-XRD, SEM, and UV-Vis were employed to analyze the properties of the synthesized nanoscopic materials, revealing their potential in energy applications.
  • The NiCoFeO solid solution demonstrated exceptional electrochemical performance, including a high specific capacitance of 237 F g for supercapacitors and low overpotentials for hydrogen and oxygen evolution reactions, indicating its suitability for energy storage and generation.
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Ternary metal sulfides are currently in the spotlight as promising electroactive materials for high-performance energy storage and/or conversion technologies. Extensive research on metal sulfides has indicated that, amongst other factors, the electrochemical properties of the materials are strongly influenced by the synthetic protocol employed. Herein, we report the electrochemical performance of uncapped NiCoS and CuCoS ternary systems prepared solventless thermolysis of the respective metal ethyl xanthate precursors at 200 and 300 °C.

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