Coral-like Au/TiO₂ Hollow Nanofibers with Through-Holes as a High-Efficient Catalyst through Mass Transfer Enhancement

Abstract

One-dimensional (1D) hollow nanomaterials were widely used in the catalysis field. However, the inner surfaces of 1D hollow nanostructures could not be effectively utilized in liquid reaction because of diffusional limitation caused by the large ratio of length to diameter. In this work, a template-assisted coaxial electrospinning method was developed to prepare TiO2 hollow nanofibers with through-holes which were further employed as a carrier for Au nanoparticles. The Au/TiO2 hollow nanofibers with through-holes showed significant catalytic activity enhancement to the reduction of 4-nitrophenol in aqueous solution compared with solid and hollow nanofiber counterparts. The through-holes which provided unrestricted macropores for mass transfer in liquid solution were studied to be accounted for the catalytic activity enhancement. The through-hole structures can widen the application ranges and increase the efficiencies of zero-dimensional or 1D hollow nanomaterials.

Hollow Au@TiO2 porous electrospun nanofibers for catalytic applications

“…Electrons were released on diffusion and adsorption of borohydride ion (BH 4 À ) The obtained results on 4NP reduction were compared in Table 1 with other analogous nanobrous systems reported in literature till now. 61,63,64 The K m value of our hollow Au@TiO 2 nanobrous catalyst is higher than the solid Au/TiO 2 nano-brous catalytic system reported by Hao et al 63 and Ning et al 64 and almost comparable to the hollow nanobrous system reported by Yue et al 61 The recyclability of the Au@TiO 2 catalytic system was investigated since it is crucial for its practical application. The catalytic performance of the Au@TiO 2 system was evaluated for ve successive reaction/recovery cycles.…”

“…The reaction solution was owed towards the inner surface of the nanobers to react on active sites and form the resultant. 61 The reduction of 4-nitrophenol occurred on the active sites of AuNPs which were located in the inner surface of hollow porous nanobers. Electrons were released on diffusion and adsorption of borohydride ion (BH 4 À ) The obtained results on 4NP reduction were compared in Table 1 with other analogous nanobrous systems reported in literature till now.…”

Pd/Au Based Catalyst Immobilization in Polymeric Nanofibrous Membranes via Electrospinning for the Selective Oxidation of 5-Hydroxymethylfurfural

“…Processes 2020, 8, 45 8 of 15 SEM micrographs, recorded for all the obtained nanofibrous samples (Figure 3), show thin fibers with diameters ranging in 350-80 nm span ( Table 2). While the fibers are all thin and smooth, it was observed that inorganic component promoted fiber diameter thinning, and in particular, the presence of free unsupported AuPd NPs, decreased the average diameter around, or even below, 100 nm.…”

“…Electrospun membranes are currently being investigated as materials for the support of heterogeneous catalysts by following different technological approaches, the main one being the production of ceramic fibers that support metal nanoparticles [40]. In this case, a polymer solution containing ceramic precursors and metal salts is electrospun and subsequently heat treated under inert gas to eliminate the organic components and reduce the metal precursor to metal nanoparticles [42][43][44][45]. This approach permits the achievement of high catalytic performances by exploiting the high surface area of the fibers but suffers from the high fragility of the completely inorganic nonwoven.…”

In Situ Decoration of Gold Nanoparticles on Graphene Oxide via Nanosecond Laser Ablation for Remarkable Chemical Sensing and Catalysis

“…Nano sized particles of noble metals, particularly gold NPs (Au NPs), have ample scope in research due to their unique optical, electrical and catalytic properties and their potential applications in material science, physics, chemistry and in many interdisciplinary fields [1,2,3]. The Au NPs have the tendency of aggregation when they are in a solution on account of their superior surface energy, which results in a reduced catalytic activity and stability [4].…”