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We report an electrocatalyst of Pd nanoparticles (NPs) supported on a carbon sphere nanoarchitecture doped with sulfur (S) and nitrogen (N) atoms (PdSNC), which is designed by exploiting a palladium−rubeanic acid (Pd−RA) coordination polymer as a precursor, followed by calcination. The synthesized Pd−RA coordination polymer, as a new precursor material, is the combination of Pd, S, N, and C in its structural backbone. The in situ formation of PdSNC was achieved by controlled carbonization of the Pd−RA precursor. The doping of S and N into carbon networks modulates the electronic structure and strengthens the affinity of the Pd NPs with the carbon surface, which reveals the improved electrical and electrochemical performance of the PdSNC catalyst. The electrochemical investigation of the oxygen reduction reaction and the hydrogen evolution reaction (ORR and HER, respectively) reveals that the combination of S and N in Pd carbon is more active than mere Pd carbons. The combined benefits from the binary heteroatoms (S and N) in the carbon texture are offered to modulate the electronic structure and stabilize Pd NPs, thus augmenting the stable electrocatalytic activity as an alternative to expensive commercial PtC. The half-wave potential of the ORR for PdSNC was 0.869 V with 4.0 electron transfer, which is better than those of PdC (0.791 V), PtC (0.830 V), and its counterpart SNC (0.786 V) catalysts. Besides, the overpotential of PdSNC showing a great promise as the HER catalyst to achieve a current density of 10 mA•cm −2 is only 0.030 V, which is much better than that of PdC and comparable to that of PtC. This all-in-one-step strategy (doping and PdC formation) is a promising approach to design heteroatoms-stabilized carbon−metal composites with a high electrocatalytic performance for sustainable energy applications.

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The template‐free synthesis and the characterization of an active electrocatalyst are performed for both the hydrogen evolution and oxygen reduction reactions in acidic media. In this work, the unique chelation mode of benzene‐1,4‐dithiocarboxamide (BDCA) is first used to synthesize a novel palladium‐BDCA coordination polymer (PdBDCA) as a precursor of palladium sulfide nanoparticles‐decorated nitrogen and sulfur doped carbon (Pd4S‐SNC). The newly synthesized PdBDCA and Pd4S‐SNC nanoparticles are characterized using chemical, electrochemical, and surface analysis methods. Notably, the nanoparticles obtained at 700 °C exhibit the remarkable catalytic property for the hydrogen evolution reaction in 0.5 m H2SO4, showing the overpotential of 32 mV (vs reversible hydrogen electrode (RHE)) and Tafel slope of 52 mV dec−1, which are comparable to that of Pt/C. The catalyst also shows a high oxygen reduction activity, offering the half‐wave and onset potentials of 0.92 and 0.77 V (vs RHE) in 0.5 m H2SO4, with improved methanol tolerance and long‐term stability compared with Pt/C. The present study gives a way for the design of excellent electrocatalyst for the energy conversion devices in the corrosive acidic environment.

A pair of chiral 2D enantiomeric sheets were constructed using AgPF6 with a pair of chiral tridentate ligands. The differential pulse voltammetric (DPV) technique was found to be an effective tool for enantio-recognition of l- and d-histidines.