The rational design and controllable preparation of carbon-based catalysts for oxygen reduction reactions (ORRs) are at the core of key technologies for fuel cells and chargeable batteries in the field of advanced energy conversion and storage. In the present study, a Co species was synthesized by tuning the Zn dopant content in a bimetallic zeolitic-imidazolate framework functionalized with carbon spheres (CoZn-ZIF/CS). Using CoZn-ZIF/CS as the precursor, Co nanoparticles on N-doped carbon spheres were generated at 1000 °C (CoZn-ZIF/CS-1000). These systems were bottom-up synthesized and extensiv ely investigated for their ORR performance. The Brunauer-Emmett-Teller surface area and total pore volume with values of 586 m2 g-1 and 0.39 cm3 g-1, respectively, for the CoZn-ZIF/CS-1000 are appropriate compared to those of the porous ZIF precursor. As expected, it exhibited high-activity ORR performance in an alkaline medium with a half-wave potential of 0.82 V vs. RHE and the diffusion-limited current density is 5.11 mV cm-2. Meanwhile, the obtained CoZn-ZIF/CS-1000 electrocatalyst shows better electrochemical stability and methanol tolerance than the commercial Pt/C. Therefore, our discovery opens up a new way to regulate the catalytic performance of carbon material templates and MOF derivatives, which could be further applied in the development of highly active catalysts for applications in chemical energy utilization.

中文翻译：

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自下而上的制备多层多孔MOF修饰的碳球衍生物的方法，可有效还原氧气。

合理设计和可控地制备用于氧还原反应（ORR）的碳基催化剂是高级能量转换和存储领域中燃料电池和可充电电池关键技术的核心。在本研究中，通过调节碳球官能化的双金属沸石-咪唑盐骨架（CoZn-ZIF / CS）中的Zn掺杂剂含量来合成Co物种。使用CoZn-ZIF / CS作为前体，在1000℃下在N掺杂碳球上生成了Co纳米颗粒（CoZn-ZIF / CS-1000）。这些系统是自下而上合成的，并对其ORR性能进行了广泛的研究。与多孔ZIF前体相比，CoZn-ZIF / CS-1000的Brunauer-Emmett-Teller表面积和总孔体积分别为586 m2 g-1和0.39 cm3 g-1。如预期的那样，它在碱性介质中表现出高活性的ORR性能，其半波电位为RHE的0.82 V，扩散极限电流密度为5.11 mV cm-2。同时，所获得的CoZn-ZIF / CS-1000电催化剂显示出比市售Pt / C更好的电化学稳定性和甲醇耐受性。因此，我们的发现为调节碳材料模板和MOF衍生物的催化性能开辟了一条新途径，可进一步应用于开发用于化学能源利用的高活性催化剂。所制得的CoZn-ZIF / CS-1000电催化剂比市售Pt / C具有更好的电化学稳定性和甲醇耐受性。因此，我们的发现为调节碳材料模板和MOF衍生物的催化性能开辟了一条新途径，可进一步应用于开发用于化学能源利用的高活性催化剂。所制得的CoZn-ZIF / CS-1000电催化剂比市售Pt / C具有更好的电化学稳定性和甲醇耐受性。因此，我们的发现为调节碳材料模板和MOF衍生物的催化性能开辟了一条新途径，可进一步应用于开发用于化学能源利用的高活性催化剂。