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Oxygen defects and hollow structures positively impact pseudocapacitive properties of diffusion/surface‐controlled processes, a component of critical importance when building high‐performance supercapacitors. Hence, we fabricated hollow nickel/cobalt molybdate rods with O‐defects (D−H−NiMoO4@CoMoO4) through a soft‐template and partial reduction method, enhancing D−H−NiMoO4@CoMoO4's electrochemical performance, yielding a specific capacitance of 1329 F g−1, and demonstrating excellent durability with 95.8 % capacity retention after 3000 cycles. D−H−NiMoO4@CoMoO4 was used as the positive electrode to construct an asymmetric supercapacitor, displaying an energy density of up to 34.13 Wh kg−1 and demonstrating good predisposition towards practical applications. This work presents an effective approach to fabricate and use hollow nickel/cobalt molybdate rods with O‐defects as pseudocapacitor material for high‐performance capacitive energy storage devices. [ABSTRACT FROM AUTHOR]

Stretchable supercapacitors (SCs) have attracted significant attention in developing power‐independent stretchable electronic systems due to their intrinsic energy storage function and unique mechanical properties. Most current SCs are generally limited by their low stretchability, complicated fabrication process, and insufficient performance and robustness. This study presents a facile method to fabricate arbitrary‐shaped stretchable electrodes via 4D printing of conductive composite from reduced graphene oxide, carbon nanotube, and poly(3,4‐ethylenedioxythiophene) polystyrene sulfonate. The electrode patterns of an arbitrary shape can be deposited onto prestretched substrates by aerosol‐jet printing, then self‐organized origami (ridge) patterns are generated after releasing the substrates from holding stretchers due to the mismatched strains. The stretchable electrodes demonstrate superior mechanical robustness and stretchability without sacrificing its outstanding electrochemical performance. The symmetric SC prototype possesses a gravimetric capacitance of ≈21.7 F g−1 at a current density of 0.5 A g−1 and a capacitance retention of ≈85.8% from 0.5 to 5 A g−1. A SC array with arbitrary‐shaped electrodes is also fabricated and connected in series to power light‐emitting diode patterns for large‐scale applications. The proposed method paves avenues for scalable manufacturing of future energy‐storage devices with controlled extensibility and high electrochemical performance. [ABSTRACT FROM AUTHOR]