Electrochemical reduction of carbon dioxide (CO2RR) into value‐added chemicals is a promising tactic to mitigate global warming. However, this process resists catalyst preparation, low faradaic efficiency (FE%) towards multi‐carbon products, and insights into mechanistic understanding. Indeed, it is demonstrated that this Fe single‐atom catalyst (Fe SAC) exists in three oxygen coordination of Fe–(O)3 configuration in Nafion coated functionalized multi‐wall carbon nanotubes (Fe‐n‐f‐CNTs), which is obtained via a simple ionic exchange method under ambient conditions. The electrochemical performance reveals that Fe SACs achieve an FE of 45% and a yield rate of 56.42 µmol cm−2 h−1 at −0.8 VRHE for ethanol. In situ X‐ray analysis reveals that the Fe SACs have variable electronic states and keeps close +3 of the oxidation state at the potential range of CO2RR. The catalytic feature reduces the reaction energy and induces the electrons transferred to the adsorbed products intermediates of *COOH and *OCHO, thus promoting CO. The carboxylic functional group on the CNTs stabilizes the Fe active sites via electrostatic interaction, verified by density functional theory calculations. The yield rate of Fe SACs indicates that the Fe single‐atom site can instantly provide a large CO to help conversion of CO2‐to‐C2 product on the CNTs.

Catalysts assumed that properly designed bimetallic systems would provide superior catalytic performance due to the cooperative effects between two atoms. Dual single-atom catalyst (DSAC) PdN 4 /CuN 4 is synthesized using a simple, cost-effective, and efficient electrochemical reduction method. The palladium single-atom is prepared first by electrochemical reduction of copper phthalocyanine to create defective N 4 sites. The new structural feature is characterized by copper reduction from Cu-N 4 coordination and the formation of defected N 4 (▫ M -N 4 ) sites, which react with a Pd precursor and form PdN 4 on the host surface. The DSAC PdN 4 /CuN 4 technique synergistically improves electrocatalytic performance toward the ethylene glycol oxidation reaction. It possesses excellent glycolate selectivity (above 88%) in an alkaline solution with an onset oxidation potential as low as 0.6 V versus a reversible hydrogen electrode, compared to commercial Pd/C. The DSAC electrocatalyst is characterized by its high current density of 83.92 mA cm −2 and high faradic efficiency value (>80%) for glycolate at 1.0 V RHE . The findings suggest a promising method to synthesize the DSACs in varying transition metals to achieve highly efficient, selective, and environmentally friendly catalysts for different applications.

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Due to their importance as catalysts in many reactions and their biological activities, an interest in the synthesis and characterization of transition metal complexes containing Schiff bases is increasing. Schiff base ligands have achieved considerable attention by the scientist over the decades as potential drug agent, Azomethine linkage (-CH=N-) of Schiff base play a significant role in medical chemistry. Derivatives of Schiff bases of 4-aminoantipyrine viz, 4-(2-hydroxy-3-methoxy benzylid ene amino)-1,2-dihydro-2,3-dimethyl-1-phenylpyrazol-5-one (4) and 4-((5-methylfuran-2-yl) methylene amino)-1,2dihydro-2,3-dimethyl-1-phenylpyrazol-5-one (5) and their Co (II), Ni (II), Cu (II) complexes were successfully synthesized, the Schiff bases ligand (4) and (5) were synthesized by condensation reaction. The structures of all the synthesized ligands were confirmed by using IR, UV-Visible, 1 H NMR, and 13 C NMR. The Cu (II), Ni (II) and Co (II) complexes were confirmed by using IR and VU-Visible. The complexes are electrolytic in nature as indicated by molar conductance measurements. The data have shown that all complexes possess octahedral geometry. In-vitro antibacterial activity of all the synthesized ligands and their metal complexes were carried out by using disc diffusion method against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa bacterial strain. Compound Co (4) has exhibited better antibacterial activity than the standard drug against S. aureus (25 mm zone of inhibition compared to the standard antibiotic Oxacillin (23 mm zone of inhibition).

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