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

Abstract

To obtain high methanol conversion at high methyl formate (MF) selectivity by the thermal reaction of direct dehydrogenation of methanol is a challenging issue due to the thermodynamic restriction. Herein,...

Pd Nanoparticles Supported on N-Doped TiO2 Nanosheets: Crystal Facets, Defective Sites, and Metal–Support Interactions Boost Reforming of Formaldehyde Solution for Hydrogen Production

“…29−31 Particularly, defective sites such as of Ti 3+ or oxygen vacancy species 32−35 in TiO 2 (this defective TiO 2 is usually denoted as TiO 2−x ) usually lead to unique physicochemical properties which were found to be effective in enhancing catalytic activities in nitrobenzene hydrogenation, 36 aldehyde hydrogenation, 37 and direct dehydrogenation of methanol to methyl. 38 For instance, Pd NPs supported on defective TiO 2 (TiO 2 −V o , V o represents oxygen vacancy) exhibited enhanced hydrogenation performance of 2-methyl-3butyn-2-ol compared with commercial Lindlar catalyst, which can be attributed to the modulated electronic properties of Pd and decreased reaction barrier. 39 Similarly, the SMSI can be rationally tuned by nitrogen-doped TiO 2 to favor high nitrobenzene hydrogenation catalytic performance over supported Pd NPs.…”

“…SMSI can tune the interfacial mass transfer, change the local chemical state and microenvironment of the catalyst, modify the adsorption approaches over reactants and the follow-up transformation of reactive species, and then ultimately modulate the chemical state, reaction pathway, and catalytic behaviors. − Typical phenomena induced by SMSI are observed to investigate the effects of group VII metals and oxide supports using in situ techniques, aberration-corrected electron microscopy, and theoretical simulation and calculation. Titanium dioxide (TiO 2 ), among other semiconducting metal oxides, is one of the more investigated systems due to its low cost and versatile physicochemical properties because of its inexpensive, nontoxic, and compelling features and has thus been widely used as the support material. − Particularly, defective sites such as of Ti 3+ or oxygen vacancy species − in TiO 2 (this defective TiO 2 is usually denoted as TiO 2– x ) usually lead to unique physicochemical properties which were found to be effective in enhancing catalytic activities in nitrobenzene hydrogenation, aldehyde hydrogenation, and direct dehydrogenation of methanol to methyl . For instance, Pd NPs supported on defective TiO 2 (TiO 2 –V o , V o represents oxygen vacancy) exhibited enhanced hydrogenation performance of 2-methyl-3-butyn-2-ol compared with commercial Lindlar catalyst, which can be attributed to the modulated electronic properties of Pd and decreased reaction barrier .…”

Improving the CO2 Hydrogenation Activity of Photocatalysts via the Synergy between Surface Frustrated Lewis Pairs and the CuPt Alloy

“…Third, under the excitation of light, the electrons in TiO 2– x (OH) y /TiO 2 jumped from the valence band (VB) to the conduction band (CB), and the photogenerated electrons and holes were separated. The photogenerated electrons could transfer into the alloy particles due to the lower transfer rate of photoexcited electrons on TiO 2– x (OH) y /TiO 2 , confirmed by the small radius of the semicircle in Figure c . Fourth, the electrons on CuPt attacked the CO bond and reduced CO 2 to CO*.…”

“…The photogenerated electrons could transfer into the alloy particles due to the lower transfer rate of photoexcited electrons on TiO 2−x (OH) y /TiO 2 , confirmed by the small radius of the semicircle in Figure 4c. 69 Fourth, the electrons on CuPt attacked the C�O bond and reduced CO 2 to CO*. The photogenerated holes then oxidized the H atom to H + .…”

Alcohol Solvent Assisted Synthesis of Metallic and Metal Oxide Catalysts: As-Prepared Cu/ZnO/Al2O3 Catalysts for Low-Temperature Methanol Synthesis with an Ultrahigh Yield

“…Methanol, an important primary alcohol with 100 million metric tons manufactured around the world in 2020, can be used to produce multiple chemicals. − It can be used for fuel cells as a liquid fuel and for gasoline as an additive. , Methanol can also be transformed to olefins and aromatics on zeolite catalysts. , Because of its broad demand and application, it is critical to synthesize highly efficient catalysts for methanol synthesis.…”