The rational design of advanced structures consisting of multiple components with excellent electrochemical capacitive properties is one of the crucial hindrances to be overcome for high‐performance supercapacitors (SCs). Herein, a superfast and facile synthesis of flower‐like NiMn‐layered double hydroxides (NiMn‐LDH) with high SC performance using an electrodeposition process on nickel foam is proposed. Oxygen vacancies are then modulated via mild H2O2 treatment for the first time, significantly promoting the electrochemical energy storage performance. The oxygen‐vacancy abundant NiMn‐LDH (Ov‐LDH) reaches a maximum specific capacity of 1183 C g−1 at the current density of 1 A g−1 and retains a high capacity retention of 835 C g−1 even at a current density of up to 10 A g−1. Furthermore, the assembled asymmetric SC device achieves a high specific energy density of 46.7 Wh kg−1 at a power density of 1.7 kW kg−1. Oxygen vacancies are proven to play a vital role in the improvement of electrochemistry performance of LDH based on experimental and theoretical studies. This vacancy engineering strategy provides a new insight into SC active materials and should be beneficial for the design of the next generation of energy storage devices.

Transition‐metal phosphides have flourished as promising candidates for oxygen evolution reaction (OER) electrocatalysts. Herein, it is demonstrated that the electrocatalytic OER performance of CoP can be greatly improved by constructing a hybrid CoP/TiOx heterostructure. The CoP/TiOx heterostructure is fabricated using metal–organic framework nanocrystals as templates, which leads to unique hollow structures and uniformly distributed CoP nanoparticles on TiOx. The strong interactions between CoP and TiOx in the CoP/TiOx heterostructure and the conductive nature of TiOx with Ti3+ sites endow the CoP–TiOx hybrid material with high OER activity comparable to the state‐of‐the‐art IrO2 or RuO2 OER electrocatalysts. In combination with theoretical calculations, this work reveals that the formation of CoP/TiOx heterostructure can generate a pathway for facile electron transport and optimize the water adsorption energy, thus promoting the OER electrocatalysis.

3D carbon‐based materials with multiscale hierarchy are promising electrode materials for electrochemical energy storage and conversion applications, but the synthesis in an efficient and large‐scale way is still a great challenge. Herein, a carbon nanorod‐assembled 3D superstructure is facilely fabricated by morphology‐preserving conversion of a metal–organic framework (MOF) nanorod‐assembled superstructure. The MOF superstructure can be fabricated in one‐pot synthesis with high reproducibility and high yield by precise control of the MOF nucleation and growth. Its derived carbon inherits the nanorod‐assembled superstructure and possesses abundant micropores and nitrogen doping, which can serve as a high‐performance anode material for fast potassium storage. The superiority of the superstructure and the synergism of micropore capturing and nitrogen anchoring are verified both experimentally and theoretically.

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Nitrogen‐doped carbon materials with abundant defects and strong potassium adsorption ability have been recognized as potential anodes for potassium ion batteries (PIBs). However, the limited content and uncontrolled type of nitrogen‐doped sites hinder the further performance improvement of PIBs. Herein, this work proposes nitrogen phosphorous co‐doped hollow carbon nanofibers (PNCNFs) derived from high‐energy metal‐organic frameworks (MOFs) with an ultra‐high nitrogen content of 19.52 wt% and a high portion of more reactive pyridinic N sites. Furthermore, the highly open architecture exploded by released gases from high‐energy MOFs provides sufficient edge sites to settle the N atoms and further form pyridinic N sites induced by phosphorous dopants. The resulting PNCNFs achieve excellent potassium ion storage performance with high reversible capacity (466.2 mAh g−1), superb rate capability (244.4 mAh g−1 at 8 A g−1), and excellent cycling performance (294.6 mAh g−1 after 3250 cycles). The density functional theory calculation reveals that the N/P defects enhance the potassium adsorption ability and improve the conductivity.