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In this work, we propose a sulfonated poly (ether ether ketone) (SPEEK) composite proton-conductive membrane based on a 3-(1-hydro-imidazolium-3-yl)-propane-1-sulfonate (Him-pS) additive to break through the trade-off between conductivity and selectivity of a vanadium redox flow battery (VRFB). Specifically, Him-pS enables an oriented distribution of the SPEEK matrix to construct highly conductive proton nanochannels throughout the membrane arising from the noncovalent interaction. Moreover, the “acid–base pair” effect from an imidazolium group and a sulfonic group further facilitates the proton transport through the nanochannels. Meanwhile, the structure of the acid–base pair is further confirmed based on density functional theory calculations. Material and electrochemical characterizations indicate that the nanochannels with a size of 16.5 nm are vertically distributed across the membrane, which not only accelerate proton conductivity (31.54 mS cm–1) but also enhance the vanadium-ion selectivity (39.9 × 103 S min cm–3). Benefiting from such oriented proton-conductive nanochannels in the membrane, the cell delivers an excellent Coulombic efficiency (CE, ≈ 98.8%) and energy efficiency (EE, ≈ 78.5%) at 300 mA cm–2. More significantly, the cell maintains a stable energy efficiency over 600 charge–discharge cycles with only a 5.18% decay. Accordingly, this work provides a promising fabrication strategy for a high-performance membrane of VRFB.

‘Community of common destiny’, a new concept in China's diplomacy, has been increasingly used by the Chinese government, especially President Xi Jinping, on international occasions. Given the paucity of academic research on the concept, this paper aims to fill the gap and examine three aspects: meaning, motives and implications. Building upon the author's long observation of China's foreign policy, the paper argues that this concept of ‘community of common destiny’ is vague in meaning and loosely used by China. While initially proposed by China to mend ties with neighbouring states in the context of escalating territorial disputes, the concept constitutes part of China's long‐term strategy to maintain a peaceful ‘period of strategic opportunity’ in the first two to three decades of the 21st century to further develop itself. However, the ambiguity of the concept poses a main challenge for China to promote the acceptance of this concept by the developing world, let alone developed countries. This process demands more transparency, commitment and concrete actions from China.

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