Revealing the role of the 1T phase on the adsorption of organic dyes on MoS₂ nanosheets

Abstract

The high adsorption capacity of dyes onto the 1T-rich MoS2 samples is due to the strong binding between the hydroxide/carboxyl groups and the 1T active sites. The capacity can be tuned by controlling the ratio between 1T and 2H phases of MoS2 nanosheets.

Nanohole-boosted electron transport between nanomaterials and bacteria as a concept for nano–bio interactions

“…The affinity response values corresponded to the binding strength of bioactive molecules on the sensor surface with nanomaterials; thus, the nanoholes acted as active sites that promoted the above-described interaction. The defects in the MoS 2 lattice as active sites promoted high affinity through the binding of hydroxide and carboxyl groups to the MoS 2 nanosheet surface 19 . Density functional theory (DFT) calculations proved that the binding energy of hydroxide and carboxyl groups adsorbed to defect-rich MoS 2 was higher than that of defect-free MoS 2 nanosheets 19 .…”

“…The defects in the MoS 2 lattice as active sites promoted high affinity through the binding of hydroxide and carboxyl groups to the MoS 2 nanosheet surface 19 . Density functional theory (DFT) calculations proved that the binding energy of hydroxide and carboxyl groups adsorbed to defect-rich MoS 2 was higher than that of defect-free MoS 2 nanosheets 19 . Fourier transform infrared (FTIR) and 2D-Fourier transform infrared-correlation spectra (2D-FTIR-COS) analysis also confirmed that COO − symmetric stretching was the targeted group in NR-MoS 2 (Fig.…”

Heterophase Grain Boundary‐Rich Superparamagnetic Iron Oxides/Carbon Composite for Cationic Crystal Violet and Anionic Congo Red Dye Removal

“…Thus, these charged states and lattice defects may provide favorable conditions for attacking positively and negatively charged dyes simultaneously and the heterophase grain boundaries serve as active site to bind the chemical groups mediating dye adsorption effectively. [ 28,29 ]…”

“…Thus, these charged states and lattice defects may provide favorable conditions for attacking positively and negatively charged dyes simultaneously and the heterophase grain boundaries serve as active site to bind the chemical groups mediating dye adsorption effectively. [28,29] With this background, carbon-containing iron oxide with heterophase grain boundaries is synthesized using thermal treatment on imidazole-capped superparamagnetic (SPM) α-Fe 2 O 3 . The local structural evolution from imidazole-capped SPM α-Fe 2 O 3 to iron oxide/carbon nanocomposite with heterophase grain boundaries (hetero-IOCC) and then iron oxide/carbon nanocomposite with homophase grain boundaries (homo-IOCC) is investigated with the help of X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), Fourier transform infrared spectrometer (FTIR), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA), and Mössbauer spectroscopy.…”

Engineering the Performance and Stability of Molybdenum Disulfide for Heavy Metal Removal

“…Some of these attempts included an increase of the MoS 2 interlayer spacing that enables hydrated metal ions to access interior spaces and reach more sulfur sites for enhanced adsorption . Other attempts suggest the introduction of defects into the lattice, resulting in a disordered structure that can offer abundant unsaturated sulfur atoms, which act as adsorption or catalytic sites. , In other cases, synthesis of the metastable metallic 1T phase (as opposed to the semiconductive 2H phase) is suggested to have superior mercury adsorption kinetics and capabilities due to high density of 1T/2H grain boundary defects, which act as active sites. , Lastly, composite MoS 2 materials have been suggested to allow multifunctionality and facile extraction of the active material following use . Investigation of the active removal mechanisms and their environmental implications will enable us to deepen our understanding and gain more control over the way we engineer and implement MoS 2 and other nanoadsorbents for water treatments.…”