The potassium‐ion battery (PIB) has emerged as a promising alternative to lithium‐ion batteries. The major challenges confronted by PIB anodes lie in sluggish kinetics and poor cycling stability owing to the inherent large K+ size. Here, a hybrid of ball‐cactus‐like Bi nanospheres embedded in 3D N‐riched carbon nanonetworks (Bi NSs/NCNs) is designed and synthesized by electrospinning. As an anode, Bi NSs/NCNs exhibits an unprecedented rate (489.3 mAh g−1 at 50 A g−1) and long‐cycling performance (457.8 mAh g−1 at 10 A g−1 after 2000 cycles), outperforming all reported PIB anode materials. Such outstanding performance mainly originates from the stable solid‐electrolyte interface formed in the glyme‐based electrolyte and the unique interconnected porous nanostructure, both of which contribute to fast kinetics and high pseudocapacitive contributions upon cycling.

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The urgent need for artificially fixing CO calls for catalysts of high efficiency. The transition metal functionalized porphyrin (TMP) is one of the most important types of organic catalysts for CO reduction. However, the catalytic mechanisms of TMP in CO reduction still remain controversial. Starting from the previously neglected catalyst self-protonation model, we uncover a new CO reduction mechanism on cobalt-porphine, which involves an indirect proton transfer step occurring at the beginning of the reduction cycle. Based on this protonation mechanism, we demonstrate the different correlations between producing rate and pH for the formation of CO and methane, in good agreement with available experimental observations. Our results reveal how pH and potential affect the CO reduction process, providing important clues and insights for further optimization of TMP catalysts.