Robust Amphiphobic Few-Layer Black Phosphorus Nanosheet with Improved Stability

Xiao Liu; Yunfei Bai; Jun Xu; Qingchi Xu; Liangping Xiao; Liping Sun; Jian Weng; Yanli Zhao

doi:10.1002/advs.201901991

Robust Amphiphobic Few-Layer Black Phosphorus Nanosheet with Improved Stability

Adv Sci (Weinh). 2019 Sep 30;6(23):1901991. doi: 10.1002/advs.201901991. eCollection 2019 Dec.

Authors

Xiao Liu¹, Yunfei Bai¹, Jun Xu^{2

3

4}, Qingchi Xu^{2

3}, Liangping Xiao⁵, Liping Sun¹, Jian Weng¹, Yanli Zhao⁴

Affiliations

¹ Department of Biomaterials College of Materials Xiamen University Xiamen 361005 P. R. China.
² Department of Physics Research Institute for Biomimetics and Soft Matter Fujian Provincial Key Laboratory for Soft Functional Materials Xiamen University Xiamen 361005 P. R. China.
³ Shenzhen Research Institute of Xiamen University Shenzhen 518057 P. R. China.
⁴ Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University 21 Nanyang Link 637371 Singapore Singapore.
⁵ State Key Lab of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 P. R. China.

Abstract

Few-layer black phosphorus (FL-BP) has been intensively studied due to its attractive properties and great potential in electronic and optoelectronic applications. However, the intrinsic instability of FL-BP greatly limits its practical application. In this study, the amphiphobic FL-BP is achieved by functionalization of 1H,1H,2H,2H-perfluorooctyltrichlorosilane (PFDTS) on the surface of FL-BP. The obtained PFDTS coated FL-BP (FL-BP/PFDTS) demonstrates enhanced stability, which is not observed during significant degradation for 2 months in high moisture content environment (95% humidity). Particularly, attributing to the surface amphiphobicity, FL-BP/PFDTS exhibits strong surface water repellency in the presence of oleic acid (as the contaminant), while other passivation coating layers (such as hydrophilic or hydrophobic coating) become hydrophilicity under such conditions. Owing to this advantage, the obtained FL-BP/PFDTS demonstrates enhanced stability in high moisture content environment for 2 months, even though the surface is contaminated by oil liquid or other organic solvents (such as oleic acid, CH₂Cl₂, and N-methyl-2-pyrrolidone). The passivation of FL-BP by amphiphobic coating provides an effective approach for FL-BP stabilization toward future applications.

Keywords: amphiphobic surfaces; black phosphorus; enhanced stability; fluorinated coating; nanosheets.