Hydrophenazine-linked two-dimensional ladder-type crystalline fused aromatic network with high charge transport

Since the advent of graphene, the development of crystalline two-dimensional (2D) organic materials with semiconducting features has been extensively explored for their potential optoelectronic applica-tions. Despite extensive progress in this field, it is still challenging to realize laterally extended organic materials with high electrical trans-port properties. Here, we report a 2D ladder-type fused aromatic network (FAN) in which backbones are composed of hydrophenazine (HP) linkage (designated HP-FAN). Consequently, its 2D extended delo-calization of Ts-molecular orbitals imparts a semiconducting band gap and facilitates fast intra-chain charge transport. The as-prepared HP -FAN exhibits semiconducting features with calculated and experi-mental band gaps of approximately 1.44 and 1.54 eV, respectively, with an unusual flat band. The HP-FAN thin flakes, isolated by polydime-thylsiloxane stamping, exhibit remarkable performance in a p -type field-effect transistor (FET) and a Hall effect device. Given its laterally extended ladder-type Ts-conjugated structure, the HP-FAN has exten-sive potential for applications in thin-film optoelectronic devices.