Stable Layered Sulfur Nanosheets Prepared by One-Step Liquid-Phase Exfoliation of Natural Sublimed Sulfur with Bovine Serum Albumin for Photocatalysis

Abstract

Inspired by graphene nanosheets, one kind of two-dimensional (2D) layered nanomaterials, sulfur nanosheets (S-NSs), were prepared by direct sonication exfoliation of the sublimed sulfur suspended in an aqueous solution containing bovine serum albumin (BSA). The prepared S-NSs showed a wide range of absorption properties from ultraviolet to the visible region, distinct multiwavelength photoluminescence (PL), and a significant electrochemiluminescence (ECL) phenomenon during potential cycled scanning or potential pulse step. Moreover, the S-NSs were found to have superb stability over 2 months in air and the strong ability to be a visible-light-active element photocatalyst. The prepared S-NSs will potentially be applied in the field of photocatalysis, sensors, optoelectronics, and transistors.

Emergence of long afterglow and room temperature phosphorescence emissions from ultra-small sulfur dots

“…1c) with a prominent lattice spacing of 0.217 nm, which corresponds to the (206) diffraction plane of sublimed sulfur. [29][30][31] S dot HRTEM images 100 nm Furthermore, the chemical/elemental compositions of S-dots are confirmed by the XPS study.…”

“…28 Furthermore, the luminescence of S-dots was increased employing hydrogen peroxide to etch the surface of the S-dot, resulting in the creation of more surface states. 28,29 A few more recent reports are also available explaining the fabrication of a 2D layered morphology from 0D S-dots employing a single-step hydrothermal approach. 29 Despite effective fabrication of luminescent S-dot materials by these approaches, they suffer from numerous drawbacks such as harsh reaction conditions, complex operation, low photoluminescence quantum yield (PLQY), high power consumption, and high cost, which significantly limits the large scale production and practical applicability of S-dots.…”

“…28,29 A few more recent reports are also available explaining the fabrication of a 2D layered morphology from 0D S-dots employing a single-step hydrothermal approach. 29 Despite effective fabrication of luminescent S-dot materials by these approaches, they suffer from numerous drawbacks such as harsh reaction conditions, complex operation, low photoluminescence quantum yield (PLQY), high power consumption, and high cost, which significantly limits the large scale production and practical applicability of S-dots. Henceforth, it is highly desirable to adopt new approaches for facile and low-cost preparation methods for S-dot production.…”

Photoluminescence investigations of sulfur quantum dots synthesized by a bubbling-assisted strategy

“…These results conrm that O 2 is essential for the formation of luminescent S-dots. The TEM images and PL spectra of S-dots synthesized by different reaction time (5,12, and 72 h) were recorded (Fig. S3 †).…”

“…Furthermore, the size and surface groups pose signicant challenges to regulating the synthesis, surface structure, and size of S-dots and unveiling their emission mechanism. [12][13][14] A top-down strategy through etching bulk elemental sulfur into quantum dots under the passivation of ligands is the most widely employed synthesis method, where assembling and ssion of S-dots are involved and contest each other. 7,11,14 However, limited by the relatively long reaction time for reaching a dynamic equilibrium and the ultra-small energy barrier between the assembling and ssion effect, the reaction mechanisms are complicated to characterize, let alone to study their fundamental emission mechanisms.…”