Selective Oxidation of Glycerol: A Biomass-Derived Feedstock Using the Pt–Cu Janus Catalyst for Value-Added Products

Tuneable C3 product selectivity of glycerol electrooxidation on cubic and dendritic Pt nanocatalysts

Glycerol, being an abundant and cheap by-product of biodiesel production, has emerged as a raw material that can be recycled into value-added compounds. In the present study, Pt nanoparticles of cubic (PtCUBE) and dendritic (PtDEND) morphologies were investigated as catalysts for the glycerol electrooxidation reaction (GEOR) at 20 °C. To optimise the electrocatalytic performance and GEOR selectivity towards three-carbon (C3) products, namely lactate, glycerate, and tartronate, the effects of morphology, electrolyte composition, and applied potential were studied. At low glycerol concentrations, C-C bond cleavage was more favoured, especially on PtDEND. Both PtCUBE and PtDEND showed high C3 product selectivity up to 91% at 0.67 V vs. RHE, with lactate reaching a maximum selectivity of 68% on PtCUBE, which also exhibited the best mass and specific activities compared to PtDEND.

Shedding Light on Luminescent Janus Nanoparticles: From Synthesis to Photoluminescence and Applications

Luminescent Janus nanoparticles refer to a special category of Janus-based nanomaterials that not only exhibit dual-asymmetric surface nature but also attractive optical properties. The introduction of luminescence has endowed conventional Janus nanoparticles with many alluring light-responsive functionalities and broadens their applications in imaging, sensing, nanomotors, photo-based therapy, etc. The past few decades have witnessed significant achievements in this field. This review first summarizes well-established strategies to design and prepare luminescent Janus nanoparticles and then discusses optical properties of luminescent Janus nanoparticles based on downconversion and upconversion photoluminescence mechanisms. Various emerging applications of luminescent Janus nanoparticles are also introduced. Finally, opportunities and future challenges are highlighted with respect to the development of next-generation luminescent Janus nanoparticles with diverse applications.

Highly Photoactive Titanium Dioxide Supported Platinum Catalyst: Synthesis Using Cleaner Ultrasound Approach

Catalysts increase reaction rates; however, the surface area to volume ratio of catalysts has a vital role in catalytic activity. The noble metals such as platinum (Pt) and gold (Au) are expensive; despite this, they have proven their existence in catalysis, motivating the synthesis of supported metal catalysts. Metal catalysts need to be highly dispersed onto the support. In this investigation, an ultrasound approach has been attempted to synthesise highly photoactive titanium dioxide (TiO2) nanoparticles by the hydrolysis of titanium tetraisopropoxide in an acetone/methanol mixture. To enhance its photocatalytic activity, TiO2 was doped with Pt. The synthesised photocatalyst was characterised by techniques such as particle size analysis (PSA), XRD, FE-SEM, TEM, and EDX. The enhancement in the surface characteristics of Pt-doped TiO2 compared with bare TiO2 support was confirmed with Brunauer–Emmett–Teller (BET) analysis. The enhanced surface area and uniformity in particle size distribution at the nanoscale level were due to the effects of ultrasonic irradiation. The obtained results corroborated the size and composition of the synthesised catalysts. The size of the catalysts is in the nanometre range, and good dispersion of Pt catalysts over the TiO2 support was observed. The UV-Visible spectroscopy analysis was performed to study the optical properties of the synthesised TiO2 and Pt/TiO2 photocatalysts. An increase in the absorbance was noted when Pt was added to TiO2, which is due to the decrease in the band gap energy.

Synthesis of bimetallic Co–Pt/cellulose nanocomposites for catalytic reduction of p-nitrophenol

The sonochemical synthesis of Co–Pt nanoparticles anchored on cellulose nanofibers (CNFs) was demonstrated. An enhancement in the catalytic activity of the synthesized Co–Pt/CNF nanocomposite catalyst was observed for the reduction of p-NP due to synergy effects.