Kitchen‐Inspired Nanochemistry: Dispersion, Exfoliation, and Hybridization of Functional MoS2 Nanosheets Using Culinary Hydrocolloids. Issue 3 (20th May 2015) - Ravula, Sudhir
Abstract: As a two‐dimensional material, molybdenum disulfide (MoS2 ) has drawn wide attention due to its fascinating properties and exciting application prospects. However, in order to access these properties, which lie within single‐ or few‐layer nanosheets, the inter‐sheet van der Waals interactions within the bulk material must be adequately disrupted to exfoliate MoS2 to atomic thicknesses. The hitch with most current exfoliation methods, though, is that they employ expensive, exotic, or environmentally incompatible methods that suffer poor scalability and poor reproducibility, producing weakly stabilized sheets that retro‐aggregate. These pitfalls render many current approaches unsuitable for the development of large‐scale devices and nanocomposites, thereby making cheaper, more benign alternatives highly sought after. Herein, we present the sonication‐assisted aqueous phase exfoliation of bulk MoS2 into dispersed single‐ or few‐layer nanosheets using popular culinary hydrocolloids, including guar gum (GG), tannic acid (TA), and xanthan gum (XG). These green agents are commercially available, inexpensive, and environmentally friendly substances and act as good dispersing and exfoliating agents. Under optimized exfoliation conditions, dispersed solution concentrations of 0.24, 0.15, and 0.06 mg mL −1 were achieved for MoS2 ‐GG, MoS2 ‐TA, and MoS2 ‐XG, respectively. In addition, the sterically stabilized nanosheets were successfully decorated with gold nanoparticles via an in situ reduction by the hydrocolloids to yield plasmonic nanocomposites exhibiting excellent catalytic activity in 4‐nitrophenol reduction. Abstract : Green a‐peel : Edible culinary hydrocolloids proved to be highly effective agents for exfoliating from bulk, crystalline material few‐layered MoS2 nanosheets, which served as scaffolds for in situ gold nanoparticle generation, creating hybrid nanocatalysts.