Jiang Yi, Oh Inseon, Joo Se Hun, Buyukcakir Onur, Chen Xiong, Lee Sun Hwa, Huang Ming, Seong Won Kyung, Kim Jin Hoon, Rohde Jan-Uwe, Kwak Sang Kyu, Yoo Jung-Woo, Ruoff Rodney S
Center for Multidimensional Carbon Materials (CMCM) , Institute for Basic Science (IBS) , Ulsan 44919 , Republic of Korea.
ACS Nano. 2019 May 28;13(5):5251-5258. doi: 10.1021/acsnano.8b09634. Epub 2019 Apr 29.
The production of multifunctional pure organic materials that combine different sizes of pores and a large number of electron spins is highly desirable due to their potential applications as polarizers for dynamic nuclear polarization-nuclear magnetic resonance and as catalysts and magnetic separation media. Here, we report a polychlorotriphenylmethyl radical-linked covalent triazine framework (PTMR-CTF). Two different sizes of micropores were established by N sorption and the presence of unpaired electrons (carbon radicals) by electron spin resonance and superconducting quantum interference device-vibrating sample magnetometer analyses. Magnetization measurements demonstrate that this material exhibits spin-half paramagnetism with a spin concentration of ∼2.63 × 10 spins/mol. We also determined the microscopic origin of the magnetic moments in PTMR-CTF by investigating its spin density and electronic structure using density functional theory calculations.
由于多功能纯有机材料在动态核极化-核磁共振极化器、催化剂和磁分离介质等方面的潜在应用，制备兼具不同尺寸孔隙和大量电子自旋的此类材料具有很高的需求。在此，我们报道了一种多氯三苯甲基自由基连接的共价三嗪框架（PTMR-CTF）。通过氮吸附确定了两种不同尺寸的微孔，并通过电子自旋共振和超导量子干涉装置-振动样品磁强计分析证实了未成对电子（碳自由基）的存在。磁化测量表明，该材料表现出自旋为半整数的顺磁性，自旋浓度约为2.63×10自旋/mol。我们还通过使用密度泛函理论计算研究其自旋密度和电子结构，确定了PTMR-CTF中磁矩的微观起源。
