Long-term can-sealing protection: a stable black phosphorus nanoassembly achieved through heterogeneous hydrophobic functionalization

Black phosphorus (BP), a promising 2D material, has sparked a research boom in various areas, while its fatal atmospheric instability seriously obstructs the progress of most practical applications. To realize the novel scalable concept of can-sealing protection, the selective deposition of a series of hydrophobicallyor hydrophilically-functionalized Al2O3 nanostructured capping layers has been successfully achieved to seal the top surface of the exfoliated BP flake assemblies on Ag-patterned substrates. The hydrophobic Al2O3 columnar capping is evidenced as the most promising candidate to provide comprehensive protection against the severe rapid degradation of pristine BP even under a very high-humidity environment (RH = 85%) for a long period of time. The present work provides valuable insight into the distinct anisotropic degradation of the sealed BP flake assemblies evidently induced by the deposited hydrophobicallyor hydrophilically-functionalized Al2O3 capping.

Automated summary

Black phosphorus (BP) as a promising 2D material has sparked extensive research, but its atmospheric instability hinders practical applications. Selective deposition of hydrophobically-functionalized Al2O3 capping layers successfully seals exfoliated BP flake assemblies, with the hydrophobic Al2O3 providing the most promising protection against rapid degradation. Valuable insights into anisotropic degradation of sealed BP assemblies induced by functionalized Al2O3 capping are provided in this work.