Mahmood Javeed, Lee Eun Kwang, Jung Minbok, Shin Dongbin, Choi Hyun-Jung, Seo Jeong-Min, Jung Sun-Min, Kim Dongwook, Li Feng, Lah Myoung Soo, Park Noejung, Shin Hyung-Joon, Oh Joon Hak, Baek Jong-Beom
Center for Dimension-Controllable Organic Frameworks, School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, South Korea;
Center for Dimension-Controllable Organic Frameworks, School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology, Ulsan 44919, South Korea; Department of Chemical Engineering, Pohang University of Science and Technology, Pohang 37673, South Korea;
Proc Natl Acad Sci U S A. 2016 Jul 5;113(27):7414-9. doi: 10.1073/pnas.1605318113. Epub 2016 Jun 16.
The formation of 2D polyaniline (PANI) has attracted considerable interest due to its expected electronic and optoelectronic properties. Although PANI was discovered over 150 y ago, obtaining an atomically well-defined 2D PANI framework has been a longstanding challenge. Here, we describe the synthesis of 2D PANI via the direct pyrolysis of hexaaminobenzene trihydrochloride single crystals in solid state. The 2D PANI consists of three phenyl rings sharing six nitrogen atoms, and its structural unit has the empirical formula of C3N. The topological and electronic structures of the 2D PANI were revealed by scanning tunneling microscopy and scanning tunneling spectroscopy combined with a first-principle density functional theory calculation. The electronic properties of pristine 2D PANI films (undoped) showed ambipolar behaviors with a Dirac point of -37 V and an average conductivity of 0.72 S/cm. After doping with hydrochloric acid, the conductivity jumped to 1.41 × 10(3) S/cm, which is the highest value for doped PANI reported to date. Although the structure of 2D PANI is analogous to graphene, it contains uniformly distributed nitrogen atoms for multifunctionality; hence, we anticipate that 2D PANI has strong potential, from wet chemistry to device applications, beyond linear PANI and other 2D materials.
二维聚苯胺（PANI）的形成因其预期的电子和光电特性而引起了广泛关注。尽管聚苯胺在150多年前就已被发现，但获得原子级明确的二维聚苯胺框架一直是一个长期存在的挑战。在此，我们描述了通过固态六氨基苯三盐酸盐单晶的直接热解合成二维聚苯胺。二维聚苯胺由共享六个氮原子的三个苯环组成，其结构单元的经验式为C3N。通过扫描隧道显微镜和扫描隧道光谱结合第一性原理密度泛函理论计算揭示了二维聚苯胺的拓扑和电子结构。原始二维聚苯胺薄膜（未掺杂）的电子特性表现出双极性行为，狄拉克点为-37 V，平均电导率为0.72 S/cm。用盐酸掺杂后，电导率跃升至1.41×10³ S/cm，这是迄今为止报道的掺杂聚苯胺的最高值。尽管二维聚苯胺的结构类似于石墨烯，但它含有均匀分布的氮原子以实现多功能性；因此，我们预计二维聚苯胺从湿化学到器件应用都具有强大的潜力，超越了线性聚苯胺和其他二维材料。
