Chen Hongni, Wang Chao, Wu Han, Li Lili, Xing Yali, Zhang Chuanhui, Long Xiaojing
State Key Laboratory of Bio-fibers and Eco-textiles, Collaborative Innovation Center of Shandong Marine Biobased Fibers and Ecological Textiles, Institute of Marine Biobased Materials, College of Materials Science and Engineering, Qingdao University, Qingdao, 266071, P. R. China.
Nat Commun. 2024 Oct 25;15(1):9222. doi: 10.1038/s41467-024-53714-3.
Supramolecular polymers possess great potential in catalysis owing to their distinctive molecular recognition and dynamic crosslinking features. However, investigating supramolecular electrocatalysts with high efficiency in oxygen reduction reaction to hydrogen peroxide (ORHP) remains an unexplored frontier. Herein, we present organic polymers for ORHP by introducing cyclodextrin-containing noncovalent building blocks, affording these supramolecules with abundant dynamic bonds. The electronic states and reaction kinetics are further well-modulated via a host-guest strategy, resulting in appropriate regional electron binding force and controllable chemical activity. Notably, integrating supramolecular units into phenyl group-containing model covalent polymer achieves a production rate of 9.14 mol g h, with 98.01% Faraday efficiency, surpassing most reported metal-free electrocatalysts. Moreover, the dynamic bonds in supramolecular catalysts can effectively regulate the binding ability of oxygen intermediates, leading to high reactivity and selectivity for the 2e pathway. Supported by theory calculation and in situ experiment, C atoms (site-1) adjacent to the -C = N (N) group are potential active sites. This work pioneers host-guest strategy and provides inspiring ideas for the ORHP process.
超分子聚合物因其独特的分子识别和动态交联特性在催化领域具有巨大潜力。然而,研究在氧还原制过氧化氢(ORHP)中具有高效性的超分子电催化剂仍是一个未被探索的前沿领域。在此,我们通过引入含环糊精的非共价结构单元来制备用于ORHP的有机聚合物,赋予这些超分子丰富的动态键。通过主客体策略进一步对电子态和反应动力学进行良好调控,从而产生合适的区域电子结合力和可控的化学活性。值得注意的是,将超分子单元整合到含苯基的模型共价聚合物中,实现了9.14 mol g⁻¹ h⁻¹的产率,法拉第效率为98.01%,超过了大多数已报道的无金属电催化剂。此外,超分子催化剂中的动态键能够有效调节氧中间体的结合能力,从而对2e途径具有高反应活性和选择性。在理论计算和原位实验的支持下,与-C=N(N)基团相邻的C原子(位点-1)是潜在的活性位点。这项工作开创了主客体策略,并为ORHP过程提供了启发思路。