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The most widely used support in low-temperature fuel cell applications is the commercially available Vulcan XC-72. Herein, we report its functionalization with the home-obtained mesityl copper (Cu-mes) and Cu coordinate (Cu-(dmpz)-L2) organometallic compounds. Pd nanoparticles are anchored on the supports obtaining Pd/CCu‑mes, Pd/CCu(dmpz)L2, and Pd/C (on nonfunctionalized support). The polarization curves of the ethanol oxidation reaction (EOR) show that Pd/CCu‑mes and Pd/CCu(dmpz)L2 promote the reaction at a more negative onset potential, i.e., Eonset = 0.38 V/reversible hydrogen electrode (RHE), compared to 0.41 V/RHE of Pd/C. The mass current density (jm) delivered by Pd/CCu‑mes is considerably higher (1231.3 mA mgPd–1), followed by Pd/CCu(dmpz)L2 (1001.8 mA mgPd–1), and Pd/C (808.3 mA mgPd–1). The enhanced performance of Pd/CCu‑mes and Pd/CCu(dmpz)L2 for the EOR (and tolerance to CO poisoning) is attributed to a shift of their d-band center toward more negative values, compared to Pd/C, because of the formation of PdCu alloyed phases arising from the functionalization. In addition, laboratory-scale tests of the anion exchange membrane-direct ethanol fuel cell assembled with Pd/CCu‑mes show the highest open circuit voltage (OCV = 0.60 V) and cell power density (Pcell = 0.14 mW cm–2). As a result of its high catalytic activity, Pd/CCu‑mes can find application as an anode nanocatalyst in AEM-DEFCs. [ABSTRACT FROM AUTHOR]

The present work reports a facile strategy to develop L-arginine mediated Zn doped graphitic carbon nitride (g-C3N4) and its enhanced photocatalytic activity. The physicochemical properties of Zn-doped g-C3N4 were studied extensively by XPS, UV–Vis, XRD, SEM and BET analysis. The studied properties of the photocatalyst were then correlated with its photocatalytic hydrogen production rates. Zn doping was evidenced by the presence of Zn-N peak from high-resolution core level XPS spectral analysis. Photocatalytic hydrogen evolution experiments revealed that, upon Zn doping, the hydrogen production rate of g-C3N4 was increased from 34.6 to 78.7 µmol/g.h, i.e. 2.3 times more. The enhancement in the photocatalytic properties after Zn doping was addressed by estimating changes in the positions of conduction band minimum and valence band maximum through XPS valence band spectral analysis. [ABSTRACT FROM AUTHOR]