02744nas a2200253 4500008004100000022001400041245019800055210006900253260000900322300001600331490000600347520172200353653003302075653002102108653002102129653006502150653002402215653002202239653003102261100002202292700002002314700002402334856013202358 2025 eng d a2574-096200a3D-architectured Pt-carbon electrodes for PEM fuel cells with tuned porosity and ionomer distribution-a micromanaged approach for improving activation, ohmic, and mass transport characteristics0 a3Darchitectured Ptcarbon electrodes for PEM fuel cells with tune cDEC  a18158-181700 v83 a

The conventional catalyst layer in Proton Exchange Membrane Fuel Cells (PEMFCs) suffers the limitation of masked active sites, hindered proton transportation, excessive water clogging, and irregular ionomer distribution, resulting in an underutilized catalyst. To overcome these challenges, an innovative catalyst layer (CL) is constructed by aligning Vulcan carbon (VC) particles along a 3D carbon nitride interconnected network originating from a melamine sponge. This forms a robust scaffold rich in anchoring sites like sulfur and nitrogen for the Pt nanoparticle. The resultant 3D CL exhibits a doubled through-plane proton transport conductivity from 23 to 41 mS cm-1, delivering a 17.3% increase in the current density at 0.60 V compared to a conventional VC CL. This strategy enables enhanced ionomer incorporation, yielding a 19.60% enhancement in the ionomer coverage over the Pt without sacrificing the porosity, as verified by a mercury porosimeter. Kelvin probe force microscopy confirms a more uniform electron density across the 3D CL, in contrast to the traditional CL, suggesting uniform coverage. The advanced porosity and structure of the 3D CL allow the mass transport regions to shift to higher current densities, with an increase of 0.30 A cm-2 at 0.50 V compared to the VC CL. The improved ionomer coverage also demonstrates 19% lower voltage degradation at 0.80 A cm-2. Further, the impedance mapping across the entire current range graphically illustrates the 3D CL's advantage in the activation, Ohmic, and mass transport regions, showing a parabolic profile with a flattened bottom attributed to the reduced Ohmic resistance and its extension to delay the mass transport losses.

10a3D-structured catalyst layer10aimpedancemapping10aionomer coverage10alow-temperature proton exchange membranefuel cell (LT-PEMFC)10amercury porosimeter10aproton resistance10atriplephase boundary (TPB)1 aSingh, Mayank, U.1 aMathew, Grigory1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/3d-architectured-pt-carbon-electrodes-pem-fuel-cells-tuned-porosity-and-ionomer-distribution02443nas a2200313 4500008004100000022001400041245012100055210006900176260000800245490000600253520146100259653000801720653001701728653000801745653001501753653000801768653001501776100001801791700002001809700003001829700001701859700002201876700001401898700002201912700002101934700002101955700002401976856012902000 2025 eng d a2366-748600aBinder-free in situ interface reconstruction of NiMoO4 nanorods over Ni(OH)2 nanosheets for efficient urea oxidation0 aBinderfree in situ interface reconstruction of NiMoO4 nanorods o cDEC0 v93 a

Replacing the energy-intensive oxygen evolution reaction (OER) with the urea oxidation reaction (UOR) in electrochemical water splitting offers simultaneous green hydrogen production and urea-rich wastewater oxidation, enhancing energy efficiency and economic viability. In this study, a non-noble metal-based binder-free NiMoO4/Ni(OH)2/NF electrocatalyst is developed, featuring NiMoO4 nanorods anchored on Ni(OH)2 nanosheets. This unique morphology facilitates a highly active in situ reconstructed interface, delivering a current density of 134 mA cm-2 at 1.40 V (vs RHE) in 1 m KOH with 0.33 m urea, significantly outperforming its individual components. The catalyst demonstrates excellent stability over 50 h at 30 mA cm-2. When integrated into an anion exchange membrane urea electrolyser (13 cm2 area) with Pt@C/NF as the HER cathode, the system achieves 192 mA cm-2 at 1.60 V. The post-UOR studies confirm the presence of an amorphous NiMoO4-crystalline Ni(OH)2 interface, which plays a key role in enhancing the availability of the active sites to enhance the UOR performance. The improved electrochemical performance of the engineered catalyst can be ascribed to the in situ reconstructed amorphous-crystalline interface, optimal hydrophilicity, reduced charge transfer resistance, and the distinct morphology. This strategy offers a promising pathway for developing highly active electrocatalysts for energy conversion applications.

10aAEM10aelectrolyser10aOWS10atomography10aUOR10awastewater1 aKumar, Yogesh1 aBarik, Sidharth1 aKharabe, Geeta, Pandurang1 aTorris, Arun1 aSingh, Mayank, U.1 aMohan, S.1 aGalave, Chaitanya1 aTekawadia, Jyoti1 aKanawade, Rajesh1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/binder-free-situ-interface-reconstruction-nimoo4-nanorods-over-nioh2-nanosheets-efficient02589nas a2200325 4500008004100000022001400041245014000055210006900195260000800264490000700272520142200279653002001701653001901721653002801740653002801768653003001796653003901826653001601865653001801881653005001899100002201949700002401971700002701995700002402022700001802046700002602064700001802090700002402108856013102132 2025 eng d a1613-681000aHot injection assisted electronically modulated twin and grain boundary rich sub-2 nm pt3co alloy resistant to phosphate ion for PEMFCs0 aHot injection assisted electronically modulated twin and grain b cMAY0 v213 a

Modulation of the electronic d-band center, structural defects (line defects), and particle size of Pt3Co alloy electrocatalyst have huge significance in elevating its electrochemical oxygen reduction reaction activity. Deviating from traditional high-temperature strategies, the current work focuses on ripening these benefits by implying a simple economically viable hot-injection-assisted modified polyol process. A conclusive control over decrementing particle size starting from 2.7 to 1.3 nm, an increasing degree of strain (twin boundary), and shifting of the d-band center away from the Fermi level are obtained via varying the temperature to which the solution is injected. The catalyst prepared via the injection at 200 degrees C (Pt3Co(1.3 t,g-b)/fVC-200) has delivered an electrochemical surface area of 84 m(2) g(Pt)(-1) with the onset and half-wave potentials of 0.980 and 0.858 V, respectively, versus RHE and a limiting current of -6.0 mA cm(-2) with stability till 20k cycles. In the high-temperature proton exchange membrane fuel cell Pt3Co(1.3 t,g-b)/fVC-200-based cell has outperformed Pt/C rendering 600 mWcm(-2) under H-2-Air compared to 529 mWcm(-2) of Pt/C with 20% lower Pt loading and double the stability due to enhanced resistance toward phosphoric acid for accelerated voltage cycling. A similar enhancement is seen while employing the catalyst for low-temperature fuel cells.

10aelectrocatalyst10agrain boundary10ahot injection synthesis10amodified polyol process10aoxygen reduction reaction10aproton exchange membrane fuel cell10aPt3Co alloy10atwin boundary10avalance band X-ray photoelectron spectroscopy1 aSingh, Mayank, U.1 aJadhav, Swapnil, D.1 aShivankar, Bhavana, R.1 aPandikassala, Ajmal1 aKumar, Yogesh1 aKrishnamurty, Sailaja1 aVinod, C., P.1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/hot-injection-assisted-electronically-modulated-twin-and-grain-boundary-rich-sub-2-nm-pt3co02452nas a2200229 4500008004100000022001400041245013900055210006900194260000800263490000600271520157000277653003001847653003001877653004301907100002401950700002701974700002202001700002402023700002002047700002402067856013102091 2025 eng d a2366-748600aPt-based 3D electrocatalyst with process-friendly features for PEMFCs possessing fast activation and improved mass-transfer properties0 aPtbased 3D electrocatalyst with processfriendly features for PEM cAPR0 v93 a

Polymer-electrolyte-membrane fuel cells (PEMFCs) face the challenges like slow oxygen reduction reaction (ORR) kinetics and limited mass transport at high current densities, which affects their performance. The efficient water removal from the cathode is essential to improve oxygen diffusion. Addressing this, a catalyst is presented with platinum (Pt) nanoparticles distributed within a 3D carbon network (Pt/3DPDC) derived from the polydopamine-coated melamine foam. This unique architecture enhances Pt utilization and water management due to its high porosity and ample free spaces, providing a process-friendly feature for the electrode under PEMFC conditions. The pores and accessible texture of the 3D polydopamine derived carbon (3DPDC) framework facilitate ionomer uptake during the electrode fabrication, extending the active triple-phase boundary and improving the membrane electrode assembly (MEA) performance. The high porosity of Pt/3DPDC is mitigated by adding a small amount of commercial fuel cell catalayst (Pt/C), which maintains the effective catalyst number density per unit area by utilizing the excess porosity of the 3DPDC framework. This controlled interplay of the unique catalyst structure and spatially confined distribution of Pt/C within the Pt/3DPDC framework offers fast activation, reduced electrode flooding, and improved current densities across the operating potential window. This carefully engineered catalyst, designed through bottom-up strategies, is a promising electrocatalyst for practical PEMFC applications.

10aOxygen Evolution Reaction10aoxygen reduction reaction10arechargeable flexible zinc-air battery1 aPandikassala, Ajmal1 aNadumattuvayil, Varsha1 aSingh, Mayank, U.1 aJadhav, Swapnil, D.1 aYoyakki, Athira1 aKurungot, Sreekumar uhttps://library.ncl.res.in/content/pt-based-3d-electrocatalyst-process-friendly-features-pemfcs-possessing-fast-activation-and