Impacts of Imidazolate Ligand on Performance of Zeolitic-Imidazolate Framework-Derived Oxygen Reduction Catalysts,ACS Energy Letters

当前位置： X-MOL 学术 › ACS Energy Lett. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Impacts of Imidazolate Ligand on Performance of Zeolitic-Imidazolate Framework-Derived Oxygen Reduction Catalysts
ACS Energy Letters ( IF 19.3 ) Pub Date : 2019-09-23 , DOI: 10.1021/acsenergylett.9b01740
Hao Wang _{1,

2} , Lauren R. Grabstanowicz ₁ , Heather M. Barkholtz ₁ , Dominic Rebollar _{1,

3} , Zachary B. Kaiser ₁ , Dan Zhao ₄ , Biao-Hua Chen ₂ , Di-Jia Liu ₁

Affiliation

Carbon-hosted Fe–N-coordinated (Fe/N/C) materials, especially those derived from thermolysis of iron-added zinc-based zeolite-imidazolate frameworks (ZIFs), have emerged as the most promising platinum group metal-free (PGM-free) oxygen reduction reaction (ORR) catalysts. However, the impacts of the precursory ZIF structure and their conversion chemistry during thermal activation to the final catalytic activity remain to be further explored in the process of continuously refining the catalyst performance. Herein, we synthesized a series of Fe-doped ZIFs with different imidazolate ligands and systematically studied the correlation between the crystal structures with the final ORR catalytic activity in an alkaline electrolyte. We also investigated the ZIF decomposition chemistry during pyrolysis using a thermogravimetric mass-spectroscopic analysis. We demonstrated that imidazole side-chain substitution alters the ZIF’s decomposition during pyrolysis, influencing the elemental compositions, surface properties, graphitization levels, and ultimately the catalytic performance. The Zn(mIm)₂TPIBP catalyst affords the highest ORR activity with a half-wave potential of 0.93 V vs RHE, representing the best among all PGM-free catalysts studied.

中文翻译：

咪唑化物配体对沸石-咪唑化物骨架衍生的氧还原催化剂性能的影响

碳基Fe–N配位（Fe / N / C）材料，特别是那些热分解添加铁的锌基沸石-咪唑酸盐骨架（ZIFs）的材料，已成为最有前途的无铂族金属（PGM）氧还原反应（ORR）催化剂。但是，在连续改进催化剂性能的过程中，前驱ZIF结构及其在热活化过程中的转化化学对最终催化活性的影响仍有待进一步探讨。在这里，我们合成了一系列具有不同咪唑酸酯配体的铁掺杂ZIF，并系统地研究了晶体结构与碱性电解质中最终ORR催化活性之间的相关性。我们还使用热重质谱分析方法研究了热解过程中的ZIF分解化学。我们证明了咪唑侧链取代改变了热解过程中ZIF的分解，影响了元素组成，表面性质，石墨化水平，并最终影响了催化性能。锌（mIm）₂ TPIBP催化剂具有最高的ORR活性，相对于RHE的半波电势为0.93 V，在所有研究的无PGM的催化剂中代表最好的。

更新日期：2019-09-23

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南