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The development of efficient and highly durable materials for renewable energy conversion devices is crucial to the future of clean energy demand. Herein, cage‐like quasihexagonal structured platinum nanodendrites decorated over the transition metal chalcogenide core (CoS2)‐N‐doped graphene oxide (PtNDs@CoS2‐NrGO) through optimized shape engineering and structural control technology are fabricated. The prepared electrocatalyst of PtNDs@CoS2‐NrGO is effectively used as anodic catalyst for alcohol oxidation in direct liquid alcohol fuel cells. Notably, the prepared PtNDs@CoS2‐NrGO exhibits superior electrocatalytic performance toward alcohol oxidation with higher oxidation peak current densities of 491.31, 440.25, and 438.12 mA mgpt–1 for (methanol) C1, (ethylene glycol) C2, and (glycerol) C3 fuel electrolytes, respectively, as compared to state‐of‐the‐art Pt‐C in acidic medium. The electro‐oxidation durability of PtNDs@CoS2‐NrGO is investigated through cyclic voltammetry and chronoamperometry tests, which demonstrate excellent stability of the electrocatalyst toward various alcohols. Furthermore, the surface and adsorption energies of PtNDs and CoS2 are calculated using density functional theory along with the detailed bonding analysis. Overall, the obtained results emphasize the advances in effective precious material utilization and fabricating techniques of active electrocatalysts for direct alcohol oxidation fuel cell applications.

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Zinc‐air batteries are gaining popularity as viable energy sources for green energy storage technologies. The cost and performance of Zn‐air batteries are mostly determined by the air electrodes in combination with an oxygen electrocatalyst. This research aims at the particular innovations and challenges relating to air electrodes and related materials. Here, a nanocomposite of ZnCo2Se4@rGO that exhibits excellent electrocatalytic activity for the oxygen reduction reaction, ORR (E1/2 = 0.802 V), and oxygen evolution reaction, OER (η10 = 298 mV@10 mA cm−2) is synthesized. In addition, a rechargeable zinc‐air battery with ZnCo2Se4@rGO as the cathode showed a high open circuit voltage (OCV) of 1.38 V, a peak power density of 210.4 mW cm−2, and outstanding long‐term cycling stability. The electronic structure and oxygen reduction/evolution reaction mechanism of the catalysts ZnCo2Se4 and Co3Se4 are further investigated using density functional theory calculations. Finally, a perspective for designing, preparing, and assembling air electrodes is suggested for the future developments of high‐performance Zn‐air batteries.