Water-soluble VS2 quantum dots with unusual fluorescence for biosensing

Abstract Quantum dots (QDs) derived from two-dimensional transition metal dichalcogenides (TMDs) are emerging extraordinary zero-dimensional materials with interesting photoelectric properties and versatile applications in optoelectronics, imaging, sensing, catalysis, energy and so on. As a typical metallic member of TMDs, vanadium disulfide (VS 2 ) is stimulating high expectation on the novel functional material. In this work, high-quality water-soluble VS 2 quantum dots (QDs) with lateral size of ∼3.3 nm is unprecedentedly achieved via a facile hydrothermal approach. The as-prepared VS 2 QDs displays uniform distribution, high stability and unusual fluorescence (UV and NIR excitation), which has been demonstrated as a signal indicator for the first time to establish a “turn-on” sensing platform for biomolecules. Based on the efficient fluorescence resonance energy transfer from VS 2 QDs to MnO 2 nanosheets and the fast redox reaction between MnO 2 and glutathione (GSH), the proposed sensor exhibits good assay performances including wide detection range, satisfying sensitivity and high selectivity for GSH under UV and NIR irradiation. The research on VS 2 quantum dots is still at its infant stage with great potentials largely unexploited.