Cho Eun Jin, Kim Bo-Min, Moon WooYeon, Park Dong Gyu, Ju Young-Wan, Choi Won Ho, Shin Jeeyoung
Department of Mechanical Systems Engineering, Sookmyung Women's University Seoul 04310 Republic of Korea
Department of Chemical and Biological Engineering, Sookmyung Women's University Seoul 04310 Republic of Korea.
Nanoscale Adv. 2024 Sep 16;6(22):5646-53. doi: 10.1039/d4na00203b.
Graphitic carbon exhibits distinctive characteristics that can be modulated by varying the number of carbon layers. Here, we developed a method to control the growth of graphitic carbon layers through pyrolysis of zeolitic imidazolate frameworks (ZIFs). The key is to pyrolyze hollow-structured ZIF-8 containing Co ions to simultaneously obtain an amorphous carbon source for graphitic carbons and Co metal nanoparticles for catalyzing graphitization of amorphous carbons. Owing to sparsely distributed Co ions within ZIF-8, Co nanoparticles are formed, which leads to localized graphitization. The graphitic carbon obtained contained two to five layers, unlike carbonized ZIF-67. The few-layered graphitic carbon was subjected to KOH activation and employed as a support for atomic-sized Co(OH) owing to the short routes for Co nanoparticle egress and OH ion movement. Our strategy does not involve any highly corrosive process for catalyst leaching and can even be used to produce atomic-sized Co(OH) with few-layered graphitic carbons.
石墨碳具有独特的特性，可通过改变碳层数来调节。在此，我们开发了一种通过热解沸石咪唑酯骨架（ZIFs）来控制石墨碳层生长的方法。关键在于热解含有钴离子的中空结构ZIF-8，以同时获得用于石墨碳的无定形碳源和用于催化无定形碳石墨化的钴金属纳米颗粒。由于ZIF-8内钴离子分布稀疏，形成了钴纳米颗粒，这导致局部石墨化。与碳化的ZIF-67不同，所获得的石墨碳包含两到五层。由于钴纳米颗粒逸出和氢氧根离子移动的路径较短，这种少层石墨碳经过氢氧化钾活化后用作原子级氢氧化钴的载体。我们的策略不涉及任何用于催化剂浸出的高腐蚀性过程，甚至可用于生产具有少层石墨碳的原子级氢氧化钴。
