Molecularly Engineered Black Phosphorus Heterostructures with Improved Ambient Stability and Enhanced Charge Carrier Mobility

• Published in: Advanced materials (Weinheim) Vol. 33; no. 48; pp. e2105694 - n/a
• Main Authors: Shi, Huanhuan, Fu, Shuai, Liu, Yannan, Neumann, Christof, Wang, Mingchao, Dong, Haiyun, Kot, Piotr, Bonn, Mischa, Wang, Hai I., Turchanin, Andrey, Schmidt, Oliver G., Shaygan Nia, Ali, Yang, Sheng, Feng, Xinliang
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01.12.2021
• Subjects: 2D materials; ambient stability; black phosphorus; Carrier mobility; charge carrier mobility; Charge transfer; Charge transport; Coupling (molecular); Current carriers; Electron density; Heterostructures; Interface stability; Materials science; molecular heterostructures; Outerwear; Oxidation; Phosphorus; Sheets; Transport properties; Two dimensional materials
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.202105694

Overcoming the intrinsic instability and preserving unique electronic properties are key challenges for the practical applications of black phosphorus (BP) under ambient conditions. Here, it is demonstrated that molecular heterostructures of BP and hexaazatriphenylene derivatives (BP/HATs) enable improved environmental stability and charge transport properties. The strong interfacial coupling and charge transfer between the HATs and the BP lattice decrease the surface electron density and protect BP sheets from oxidation, resulting in an excellent ambient lifetime of up to 21 d. Importantly, HATs increase the charge scattering time of BP, contributing to an improved carrier mobility of 97 cm2 V‐1 s‐1, almost three times of the pristine BP films, based on noninvasive THz spectroscopic studies. The film mobility is an order of magnitude larger than previously reported values in exfoliated 2D materials. The strategy opens up new avenues for versatile applications of BP sheets and provides an effective method for tuning the physicochemical properties of other air‐sensitive 2D semiconductors. A molecular engineering strategy is demonstrated to prepare ambient stable black phosphorus (BP)/hexaazatriphenylene (HAT) hybrid heterostructures. This strategy not only modifies the band structure of BP sheets but also improves their charge mobility, paving the way toward ambient processing and fabrication of high‐performance BP‐based devices.