Department of Chemical Engineering

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Author: search.filters.author.Pandey, JaySubject: search.filters.subject.Proton conductivity

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Now showing 1 - 4 of 4
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    Review on proton conducting membrane for PEM water electrolyser: A sustainable approach for green hydrogen production
    (Elsevier, 2025-09) Pandey, Jay
    Water electrolysis with proton exchange membranes (PEMs) holds great promise for producing green hydrogen, but the industry still leans heavily on expensive perfluorosulfonic acid membranes like Nafion. In this review, we dive into both established PFSA materials (Nafion, Aquivion, and PFSA–polymer composites) and emerging hydrocarbon-based alternatives (sulfonated poly(arylene ether sulfone), sulfonated poly(ether ether ketone), polyphenylene sulfone, and related systems). Rather than merely listing developments, we uncover how modifications at the molecular level-backbone chemistry, side-chain length, reinforcement by inorganic fillers, and crosslinking- translate into real gains in proton conductivity, mechanical strength, and chemical resilience. We also examine how these membranes behave under the harsh, acidic conditions of a working PEM water electrolyser, pinpointing the main pathways of performance loss (delamination, excessive swelling, and chemical degradation). Drawing on the latest studies, we highlight novel composite strategies-such as hybrid organic–inorganic networks and graft-copolymer architectures-that bring hydrocarbon membranes closer to PFSA benchmarks, often at dramatically lower cost. Finally, we sketch out future directions: designing acid-stable ion channels, refining scalable synthesis techniques, and integrating advanced reinforcement approaches to bridge the gap between lab-scale promise and industrial reality. By illuminating these structure–property links and proposing targeted research avenues, this review charts a clear path toward affordable, high-performance PEMs for a truly sustainable hydrogen economy.
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    Effect of Operating Variables on DMFC Performance for the Synthesized Si-PWA/PVA Nanocomposite Membrane
    (Life Science Global, 2015) Pandey, Jay
    Electrochemical Performance of DMFC was studied under the effect of various operating parameters like temperature, methanol concentration and relative humidity (RH) for the synthesized silica immobilized phosphotungstic acid-poly(vinyl alcohol) (Si-PWA/PVA) nanocomposite membrane (thickness 80-100 µm). The optimized 1.5 Si-PWA/PVA membrane showed good electrochemical properties (transport number: 0.92 and IEC: 0.90 meq/g) with excellent mechanical strength, thermal and chemical stability. Open circuit voltage (OCV) decay was significantly lower in comparison to Nafion-117. Maximum power density (45.7 mWcm-2) was obtained at 60oC cell temperature. DMFC performance exhibited better performance even at higher methanol concentration (2 M) demonstrating lower concentration over potential. The appreciable rise in the peak power density observed at higher relative humidity (90%) showed good water stability of the membrane. Performance of the DMFC with the synthesized composite membrane was comparable to the state of the art Nafion-117.
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    PVDF supported silica immobilized phosphotungstic acid membrane for DMFC application
    (Elsevier, 2014-09) Pandey, Jay
    Silica immobilized phosphotungstic acid (Si-PWA) based inorganic–organic hybrid ion exchange membrane was used in direct methanol fuel cell (DMFC). Chemical composition of the ion exchanging phase of membrane was determined using energy dispersive spectroscopy (EDS). TGA analysis showed that the thermal stability of synthesized membrane was better than Nafion-117 and it also possessed excellent water holding capacity even at elevated temperature. The proton conductivity of the membrane increased upon increasing the PWA concentration in silica. Room temperature (25 °C) proton conductivity of the membrane was 4.3 m Scm− 1 and it increased to 10.1 m Scm− 1 upon increasing temperature to 60 °C. At 25 °C and 60% relative humidity, the peak power density of DMFC with synthesized membrane (21.6 m Wcm− 2) was much better than that of DMFC with Nafion-117 membrane (11 m Wcm− 2).
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    Synthesis of silica immobilized phosphotungstic acid (Si-PWA)-poly(vinyl alcohol) (PVA) composite ion-exchange membrane for direct methanol fuel cell
    (Elsevier, 2014-06) Pandey, Jay
    A 80 μm thick composite ion-exchange membrane was synthesized by uniformly dispersing sub-micron to nano sized silica immobilized phosphotungstic acid (Si-PWA) inorganic ion exchanger into cross-linked poly(vinyl alcohol) (PVA) matrix. ATR-IR spectrum confirmed the PVA cross-linking and presence of Si-PWA in membrane. Amorphous behavior of the membrane indicated uniform blending of crystalline Si-PWA particles with cross-linked PVA. Membrane's tensile strength (93 MPa) was much higher than Nafion 117 (34 MPa). Ion exchange capacity of the membrane (0.90 meqg−1) was higher than the values reported for the other PVA based membranes. Na+ transport number was 0.92, indicating good ion-selectivity of the membrane. Membrane showed a high water uptake of 35% while its methanol uptake was low (8.4%) and thereby reduced methanol permeability (1.6 × 10−7 cm2 s−1) compared to Nafion-117 was observed, a highly desirable property for DMFC application. Proton conductivity increased from 7.04 mS cm−1 to 10.5 mS cm−1 with increase in temperature from 30 °C to 50 °C. At 35 °C, the single cell DMFC with membrane showed higher OCV (0.8 V) and comparable peak power density to Nafion-117.