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Aqueous zinc‐ion batteries are promising energy storage devices due to their low cost, good ionic conductivity, and high safety. Conductive polyaniline is a promising cathode because of its redox activity, but because the neutral electrolyte protonates only weakly, it displays limited electrochemical activity. A polyaniline cathode is developed with proton self‐doping from manganese metal–organic frameworks (Mn–MOFs) that alleviates the deprotonation and electrochemical activity concerns arising during the charge/discharge process. The MOFs carboxyl group provides protons to prevent deprotonation and allows the polyaniline to reach a high zinc storage redox activity. The proton self‐doped polyaniline cathode has a superior specific capacity (273 mAh g−1 at 0.5 A g−1), a high rate property (154 mAh g−1 at 20 A g−1), and excellent cyclability retention (87% over 4000 cycles at 15 A g−1). This research provides fresh insight into the development of innovative polymers as cathode materials for high‐performance AZIBs. [ABSTRACT FROM AUTHOR]

Cobalt‐based catalysts are widely used as efficient activator for the activation of peroxymonosulfate (PMS). A new carbon enclosed magnetic metal cobalt (Co@C) catalyst was successfully synthesized by high‐temperature pyrolysis of cobalt‐based metal‐organic framework. The prepared Co@C catalyst demonstrated remarkable catalytic activity for the degradation of contaminants (99.9 % for tetracycline (TC) degradation within 10 min). The TC degradation efficiency could still sustain more than 99 % after three cycles. Moreover, the Co@C/PMS system exhibited great universality for the rapid removal of other dyes such as methyl orange (MO) and methylene blue (MB). The zero‐valent cobalt was engaged in the activation of the PMS and reacted with O2 to form Co2+, to make sure that there was enough Co2+ to activate PMS to generate Co3+. Simultaneously, the produced Co3+ ions extracted electrons out of HSO5- ${{{\rm { HSO}}}_{{\rm { 5}}}^{{\rm { -}}}}$ , driving a Co0/Co2+/Co3+ circulation to keep the high efficiency for rapid degradation of TC. In summary, this work offers a novel strategy to develop an effective magnetic heterogeneous catalyst to activate PMS for the elimination of difficult to degrade contaminants. [ABSTRACT FROM AUTHOR]

[Display omitted] • The porous CuS x /C exhibited excellent catalytic performance. • S-vacancies in CuS x /C are obtained via partial sulfidation and thermal annealing treatment. • S-vacancies provide abundant Cu+/Cu2+ active sites for PMS activation. Transition metal sulfides are often used as heterogeneous catalysts to activate peroxymonosulfate (PMS), but insufficient active sites on catalysts surface limited the further application. Herein, a porous carbon-based copper sulfide (CuS x /C) nanosphere with plentiful sulfur vacancies was obtained and exhibited excellent catalytic activity for degrading pollutants (97.9 % for Rhodamine B (RhB) degradation within 6 min) in PMS system, which was significantly higher than that of CuS and CuS x (7.1 % and 13.8 %). The high catalytic performance of CuS x /C was mainly attributed to the existence of plentiful sulfur vacancies and the special porous morphology, thereby more Cu+/Cu2+ exposed on the CuS x /C surface, and further provided more active sites for the activation of PMS. This research provides a new strategy to construct high performance transition metal sulfides catalysts with sufficient sulfur vacancies for activating PMS. [ABSTRACT FROM AUTHOR]