Scalable Exfoliation and High‐Efficiency Separation Membrane of Boron Nitride Nanosheets

Abstract

Hexagonal boron nitride nanosheets (h‐BNNSs) refer to a class of two‐dimensional materials with promising applications. However, the current method of exfoliating hexagonal boron nitride (h‐BN) into h‐BNNS limits its large‐scale application. Herein, a method was developed to exfoliate h‐BN through sucrose assisted discontinuous, multiple ball milling. A series of defect‐free, ultra‐thin large lateral‐size h‐BNNSs were successfully obtained, with a yield as high as 85 wt %. Finally, the membranes of BNNS obtained by vacuum filtration displayed a good separation performance in different organic pigment solutions. The separation rates of BNNS‐20 membranes for methylene blue and Congo red reached 87 % and 95 %, respectively. The results show that the functionalized h‐BNNSs obtained by sucrose‐assisted discontinuation, multiple ball milling have good stability in water, and hence can be applied to wastewater treatment.

Optical and structural properties of H-BN@Gd2O3 nanoflake prepared by laser–induced ablation in liquid

“…The colloidal nature of the nanoparticle solutions was further validated by examining the Tyndall effect in solutions irradiated with green wavelength laser beams, as shown in figures 6(A)-(D). The path of a green laser beam can be clearly observed in all colloidal (B-D) due to light scattering by a few layers of BN, Gd 2 O 3 , and BN@ Gd 2 O 3 colloidal (Tyndall effect), but (A) the laser is not visible in deionized distilled water [50,51].Despite the fact that the solution is practically clear under daylight, the BNNS, Gd 2 O 3 Ns, and BN@ Gd 2 O 3 nanocomposite produce high photoluminescence (PL) by generating blue, pink, purple, and intense blue luminescence under UV light (220 nm), as shown in figures 7 and 8.…”

Supplementary document for Investigation of photon emitters in Ce-implanted hexagonal boron nitride - 5430459.pdf

“…Hexagonal boron nitride (hBN) flakes are dry-exfoliated from high-quality bulk single-crystal and dry-transferred onto a patterned SiO 2 substrate with an array of 50x50 µm 2 edged holes (Figure 1a). Within this approach, the high-quality properties of the bulk hBN crystal remain unchanged, as demonstrated elsewhere [1][2][3]. Typical hBN flakes range from 10 to 50 µm in lateral size, with average thickness of ~50-100 nm based on white-light reflection [4,5].…”