07169nas a2200181 4500008004100000245014400041210006900185260000800254300001200262490000600274520645000280100002306730700002906753700001706782700002806799700003006827856013006857 2024 eng d00aElectrocatalytic and selective oxidation of glycerol to formate on 2D 3d-metal phosphate nanosheets and carbon-negative hydrogen generation0 aElectrocatalytic and selective oxidation of glycerol to formate  cJUN a500-5110 v43 a

In the landscape of green hydrogen production, alkaline water electrolysis is a well-established, yet not-so-cost-effective, technique due to the high overpotential requirement for the oxygen evolution reaction (OER). A low-voltage approach is proposed to overcome not only the OER challenge by favorably oxidizing abundant feedstock molecules with an earth-abundant catalyst but also to reduce the energy input required for hydrogen production. This alternative process not only generates carbon-negative green H2 but also yields concurrent value-added products (VAPs), thereby maximizing economic advantages and transforming waste into valuable resources. The essence of this study lies in a novel electrocatalyst material. In the present study, unique and two-dimensional (2D) ultrathin nanosheet phosphates featuring first-row transition metals are synthesized by a one-step solvothermal method, and evaluated for the electrocatalytic glycerol oxidation reaction (GLYOR) in an alkaline medium and simultaneous H2 production. Co3(PO4)2 (CoP), Cu3(PO4)2 (CuP), and Ni3(PO4)2 (NiP) exhibit 2D sheet morphologies, while FePO4 (FeP) displays an entirely different snowflake-like morphology. The 2D nanosheet morphology provides a large surface area and a high density of active sites. As a GLYOR catalyst, CoP ultrathin (∼5 nm) nanosheets exhibit remarkably low onset potential at 1.12 V (vs RHE), outperforming that of NiP, FeP, and CuP around 1.25 V (vs RHE). CoP displays 82% selective formate production, indicating a superior capacity for C–C cleavage and concurrent oxidation; this property could be utilized to valorize larger molecules. CoP also exhibits highly sustainable electrochemical stability for a continuous 200 h GLYOR operation, yielding 6.5 L of H2 production with a 4 cm2 electrode and 98 ± 0.5% Faradaic efficiency. The present study advances our understanding of efficient GLYOR catalysts and underscores the potential of sustainable and economically viable green hydrogen production methodologies.

1 aChauhan, Inderjeet1 aVijay, Pothoppurathu, M.1 aRanjan, Ravi1 aPatra, Kshirodra, Kumar1 aGopinath, Chinnakonda, S. uhttps://library.ncl.res.in/content/electrocatalytic-and-selective-oxidation-glycerol-formate-2d-3d-metal-phosphate-nanosheets02539nas a2200289 4500008004100000022001400041245014400055210006900199260000900268300001600277490000700293520157100300653002101871653001301892653001901905653001301924653001401937653000801951100002301959700002101982700001802003700002302021700001902044700002802063700003002091856012802121 2024 eng d a1944-824400aElectrocatalytic glycerol conversion: a low-voltage pathway to efficient carbon-negative green hydrogen and value-added chemical production0 aElectrocatalytic glycerol conversion a lowvoltage pathway to eff cMAY  a26130-261410 v163 a

Electrochemical glycerol oxidation reaction (GLYOR) could be a promising way to use the abundantly available glycerol for production of value-added chemicals and fuels. Completely avoiding the oxygen evolution reaction (OER) with GLYOR is an evolving strategy to reduce the overall cell potential and generate value-added chemicals and fuels on both the anode and cathode. We demonstrate the morphology-controlled palladium nanocrystals, afforded by colloidal chemistry, and their established morphology-dependent GLYOR performance. Although it is known that controlling the morphology of an electrocatalyst can modulate the activity and selectivity of the products, still it is a relatively underexplored area for many reactions, including GLYOR. Among nanocube (Pd-NC), truncated octahedron (Pd-TO), spherical and polycrystalline (Pd-PC) morphologies, the Pd-NC electrocatalyst deposited on a Ni foam exhibits the highest glycerol conversion (85%) along with 42% glyceric acid selectivity at a low applied potential of 0.6 V (vs reversible hydrogen electrode (RHE)) in 0.1 M glycerol and 1 M KOH at ambient temperature. Owing to the much favorable thermodynamics of GLYOR on the Pd-NC surface, the assembled electrolyzer requires an electricity input of only similar to 3.7 kWh/m(3) of H-2 at a current density of 100 mA/cm(2), in contrast to the requirement of >= 5 kWh/m(3) of H-2 with an alkaline/PEM electrolyzer. Sustainability has been successfully demonstrated at 10 and 50 mA/cm(2) and up to 120 h with GLYOR in water and simulated seawater.

10aelectrocatalysis10aGlycerol10agreen hydrogen10ananocube10aPalladium10aSDG1 aChauhan, Inderjeet1 aBajpai, Himanshu1 aRay, Bishakha1 aKolekar, Sadhu, K.1 aDatar, Suwarna1 aPatra, Kshirodra, Kumar1 aGopinath, Chinnakonda, S. uhttps://library.ncl.res.in/content/electrocatalytic-glycerol-conversion-low-voltage-pathway-efficient-carbon-negative-green02529nas a2200277 4500008004100000022001400041245014800055210006900203260000800272300001600280490000700296520157200303653001901875653002401894653002201918653002901940653001601969653002301985100001702008700002002025700001702045700002302062700001802085700001702103856013102120 2025 eng d a1944-824400aEnhanced electrocatalytic performances of NiCr layered double hydroxides by oxalate intercalation in anion exchange membrane water electrolysis0 aEnhanced electrocatalytic performances of NiCr layered double hy cJUN a37863-378780 v173 a

Layered double hydroxides (LDHs) have attracted much attention these days in the field of water electrolysis due to easy modulation in their layered structure and properties. Herein, NiCr-LDH has been developed, and its interlayer spacing has been considerably increased by oxalate intercalation. Such increased interlayer spacing allows easy access of hydroxides to a large number of electroactive sites and thereby boosts the electrocatalytic performances both for oxygen and hydrogen evolution reactions. Being very active toward both the electrocatalytic reactions, the oxalate-intercalated NiCr-LDH was further explored in an alkaline anion exchange membrane water electrolyzer (AEMWE), achieving 800 mA cm-2 at 1.88 V cell voltage at an operating temperature of 60 degrees C. In fact, the electrolyzer efficiency has been determined to be as high as 69.66%, and the calculated H2 production cost was found to be \$0.97 per gasoline-gallon equivalent, which is well below the targeted cost by the Department of Energy, USA. The electrocatalyst was also examined in harsh alkaline media, like highly saline or seawater, which also indicated its ability to carry out sustainable seawater electrolysis, restricting chlorides to a great extent. Interestingly, post-electrolysis characterization reveals the fact that oxalate decomposition aided carbonate formation within interlayers of NiCr-LDH, and high affinity toward hydroxides is responsible for restricting chlorides during the electrolysis process, apart from the great electrocatalytic activity.

10aAnion exchange10ahydrogen production10ainterlayerspacing10aLayered double hydroxide10aSustainable10awater electrolyzer1 aPal, Santanu1 aSinha, Nibedita1 aDas, Chandni1 aChauhan, Inderjeet1 aAhmed, Tanbir1 aRoy, Poulomi uhttps://library.ncl.res.in/content/enhanced-electrocatalytic-performances-nicr-layered-double-hydroxides-oxalate-intercalation