An efficient catalyst of CuPt/TiO2 for photocatalytic direct dehydrogenation of methanol to methyl formate at ambient temperature

CuPt alloy nanoparticles on TiO2 are highly effective for photocatalytic direct dehydrogenation of methanol to methyl formate at ambient temperature.

Near-Surface Gas-Phase Methoxymethanol Is Generated by Methanol Oxidation over Pd-Based Catalysts

Catalytic conversion of alcohols underlies many commodity and fine chemical syntheses, but a complete mechanistic understanding is lacking. We examined catalytic oxidative conversion of methanol near atmospheric pressure using operando small-aperture molecular beam time-of-flight mass spectrometry, interrogating the gas phase 500 μm above Pd-based catalyst surfaces. In addition to a variety of stable C_1-3 species, we detected methoxymethanol (CH₃OCH₂OH)─a rarely observed and reactive C₂ oxygenate that has been proposed to be a critical intermediate in methyl formate production. Methoxymethanol is observed above Pd, Au_xPd_y alloys, and oxide-supported Pd (common methanol oxidation catalysts). Experiments establish temperature and reactant feed ratio dependences of methoxymethanol generation, and calculations using density functional theory are used to examine the energetics of its likely formation pathway. These results suggest that future development of catalysts and microkinetic models for methanol oxidation should be augmented and constrained to accommodate the formation, desorption, adsorption, and surface reactions involving methoxymethanol.

A Ti-doped γ-Fe2O3/SDS nano-photocatalyst as an efficient adsorbent for removal of methylene blue from aqueous solutions

Synthetic dyes are among the most important environmental pollutants in wastewaters. Consequently, elimination of the synthetic dyes from wastewaters using non-toxic materials and eco-friendly technologies has been of considerable interests. In this study, magnetically separable Ti-doped γ-Fe₂O₃ photocatalysts were synthesized for the removal of methylene blue (MB) from a dye-contaminated aqueous solution (as a model of dye-polluted wastewaters). Compared to the pristine γ-Fe₂O₃, the 1.78 v% Ti-doped γ-Fe₂O₃ significantly increased the adsorption of MB by 57% in the dark condition as a result of the improved BET surface area in this photocatalyst. Moreover, the contact time required for the photocatalytic degradation of MB by the 1.78 v% Ti-doped γ-Fe₂O₃ decreased due to the higher concentration of charge carriers in this photocatalyst than that of the pristine γ-Fe₂O₃. The effect of different experimental parameters on the adsorption property and photocatalytic activity of the 1.78 v% Ti-doped γ-Fe₂O₃ photocatalyst showed that the solution pH had a remarkable influence on the removal performance of this photocatalyst. Surface treatment of the 1.78 v% Ti-doped γ-Fe₂O₃ with sodium dodecyl sulfate (SDS) resulted in the formation of a negatively charged Ti-doped γ-Fe₂O₃/SDS photocatalyst, which showed a higher tendency for the adsorption and removal of MB than the untreated photocatalyst. Moreover, the MB removal efficiency of this photocatalyst was among the best performances that have been reported for the γ-Fe₂O₃-based photocatalysts. The synthesized photocatalysts were characterized by various techniques, and a plausible mechanism for the removal of MB from aqueous solutions by the Ti-doped γ-Fe₂O₃/SDS photocatalyst was purposed.

Dwindling the re-stacking by simultaneous exfoliation of boron nitride and decoration of α-Fe2O3nanoparticles using a solvothermal route

The decoration of cube-like α-Fe₂O₃nanoparticles onin situexfoliated h-BN nanosheets was demonstrated using a solvothermal method.

A novel Cu–Mn/Ca–Zr catalyst for the synthesis of methyl formate from syngas

A novel catalyst comprised of Cu–Mn mixed oxides and CaO–ZrO₂ solid base has contributed to a high-performance methyl formate (MF) synthesis from syngas in a slurry reactor.

Highly active Au–Pd nanoparticles supported on three-dimensional graphene–carbon nanotube hybrid for selective oxidation of methanol to methyl formate

Carbon nanotubes inserted in graphene give the Au–Pd/Gr–CNT catalyst high activity in methanol oxidation to methyl formate.

Oxidation of methanol to methyl formate over supported Pd nanoparticles: insights into the reaction mechanism at low temperature

The mechanism of methyl formate formation at low temperature was studied using DRIFT-operando. The first reaction step would be the formation of methoxy groups by dissociative adsorption of methanol and then transformation into formaldehyde. The final step would be the condensation of the formaldehyde species with gaseous methanol.