Garcia-Garfido Juan M, Enríquez Javier, Chi-Durán Ignacio, Jara Iván, Vivas Leonardo, Hernández Federico J, Herrera Felipe, Singh Dinesh P
Physics Department, Faculty of Science, University of Santiago of Chile (USACH), Av. Ecuador 3493, Santiago, Estación Central 9170124, Chile.
ANID - Millennium Science Initiative Program, Millennium Institute for Research in Optics, Alto Nahuelbuta 2510, Casa 4, San Pedro de la Paz, Concepción 4130691, Chile.
ACS Omega. 2021 Jun 25;6(27):17289-17298. doi: 10.1021/acsomega.1c01272. eCollection 2021 Jul 13.
The solvothermal synthesis of metal-organic frameworks (MOFs) often proceeds through competing crystallization pathways, and only partial control over the crystal nucleation and growth rates is possible. It challenges the use of MOFs as functional devices in free-space optics, where bulk single crystals of millimeter dimensions and high optical quality are needed. We develop a synthetic protocol to control the solvothermal growth of the MOF [Zn(3-ptz)] (MIRO-101), to obtain large single crystals with projected surface areas of up to 25 mm in 24 h, in a single reaction with in situ ligand formation. No additional cooling and growth steps are necessary. We propose a viable reaction mechanism for the formation of MIRO-101 crystals under acidic conditions, by isolating intermediate crystal structures that directly connect with the target MOF and reversibly interconverting between them. We also study the nucleation and growth kinetics of MIRO-101 using ex situ crystal image analysis. The synthesis parameters that control the size and morphology of our target MOF crystal are discussed. Our work deepens our understanding of MOF growth processes in solution and demonstrates the possibility of building MOF-based devices for future applications in optics.
金属有机框架材料（MOFs）的溶剂热合成通常通过相互竞争的结晶途径进行，并且只能对晶体成核和生长速率进行部分控制。这对MOFs在自由空间光学中的功能器件应用构成了挑战，因为在该领域需要毫米尺寸且光学质量高的块状单晶。我们开发了一种合成方案来控制MOF [Zn(3-ptz)] （MIRO-101）的溶剂热生长，通过原位配体形成的单一反应，在24小时内获得投影表面积高达25平方毫米的大单晶。无需额外的冷却和生长步骤。我们通过分离与目标MOF直接相连并在它们之间可逆相互转化的中间晶体结构，提出了酸性条件下MIRO-101晶体形成的可行反应机制。我们还使用非原位晶体图像分析研究了MIRO-101的成核和生长动力学。讨论了控制目标MOF晶体尺寸和形态的合成参数。我们的工作加深了我们对溶液中MOF生长过程的理解，并展示了构建基于MOF的器件用于未来光学应用的可能性。
