Highly selective hydrogenation of cinnamaldehyde to cinnamyl alcohol with 2-propanol was achieved using SiC-supported Au nanoparticles as photocatalyst. The hydrogenation reached a turnover frequency as high as 487 h(-1) with 100% selectivity for the production of alcohol under visible light irradiation at 20 °C. This high performance is attributed to a synergistic effect of localized surface plasmon resonance of Au NPs and charge transfer across the SiC/Au interface. The charged metal surface facilitates the oxidation of 2-propanol to form acetone, while the electron and steric effects at the interface favor the preferred end-adsorption of α,β-unsaturated aldehydes for their selective conversion to unsaturated alcohols. We show that this Au/SiC photocatalyst is capable of hydrogenating a large variety of α,β-unsaturated aldehydes to their corresponding unsaturated alcohols with high conversion and selectivity.

The Mott−Schottky heterojunction in Pd/SiC can continuously transfer photogenerated electrons to Pd nanoparticles and leave holes in SiC under irradiation. The electrons in Pd particles and holes in SiC played different roles in the photocatalytic Suzuki−Miyaura coupling reaction, respectively, for cleaving the C−Br or C−I bond in benzene halides and the C−B bond in phenylboronic acids. Therefore, the intrinsic activity of Pd was dramatically enhanced when employing SiC-supported Pd nanoparticles as the photocatalyst for the coupling reaction. The Mott− Schottky-type Pd/SiC catalyst in the coupling of iodobenezene and phenylboronic acid showed a high turnover frequency of 1053 h −1 and a selectivity of nearly 100% under visible-light irradiation at 30°C. This provides a green photocatalytic route for synthesizing biaryl compounds and a facile strategy for designing novel photocatalysts for a wide range of organic transformations driven by visible light.

Fischer−Tropsch synthesis (FTS) converts carbon monoxide and hydrogen to liquid fuels and chemicals and is usually operated under high temperature ranges, which results in an evident increase of energy consumption and CO 2 emission. A photocatalytic FTS route was proposed to efficiently harvest solar energy. Worm-like ruthenium nanostructures dispersed on graphene sheets can effectively catalyze FTS at mild conditions (150°C, 2.0 MPa H 2 , and 1.0 MPa CO) under irradiation of visible light and achieve a catalytic activity as high as 14.4 mol CO ·mol Ru −1 ·h −1 . The reaction rate of FTS can be enhanced by increasing the irradiation intensity or decreasing the irradiation wavelength. The work provides a green and efficient photocatalytic route for FTS. F ischer−Tropsch synthesis (FTS), which converts carbon monoxide and hydrogen (syngas) to hydrocarbons, is an important process to produce liquid fuels and chemicals. 1−3 Traditional FTS employs coal-based syngas as the feedstock, and thus, it is hard to compete with the petroleum industry. With the increasing shortage of global fossil resources, the source of syngas has become diversified, including coal, natural gas, biomass, among others. 4−6 Meanwhile, the price of crude oil has also stayed at a high level. Therefore, FTS has gathered attention again for its ability to produce liquid fuels and chemicals from nonfossil resources. As syngas can be easily produced by biomass resource now, it would be a significant breakthrough if FTS could harvest sunlightthe most abundant energy source on the Earth.Industrial FTS catalysts are usually based upon iron or cobalt conducting under high temperatures (310−340°C for Fe catalysts or 210−260°C for Co catalysts). 7 The high temperature leads to not only high energy consumption but also increased CO 2 emission due to the water−gas shift reaction. 8 Compared to Fe and Co, Ru catalysts are somewhat expensive, but they exhibit higher intrinsic activity, higher stability, and higher selectivity to long-chain hydrocarbons. 9,10 Besides, they are capable of operating in the presence of large amounts of water. 9,10 The presence of water, whether indigenous or co-fed, can lead to a significant increase in the reaction rate of FTS over Ru-based catalysts with decreasing CH 4 selectivity and increasing C 5+ selectivity. 10 Ru is a nonplasmonic metal. Although it does not own the characteristic of so-called surface plasmon resonance, 11,12 its nanoparticles can also significantly absorb UV and visible light. 13,14 The light absorption of metal nanoparticles is generally attributed to the interband transition of bound electrons. Individual bound electrons gain the energy of incident photons and become "hot" electrons with high energy via the interband transition. These light-excited hot electrons in nanoparticles can facilitate chemical transformations of molecules adsorbed on the nanoparticles. 15−17 Recently, we found that graphene can stabilize some metastable nanoparticles, such as Cu 2 O and Cu, and enable them to exhibit stable ...

Pd/SiC exhibits a tremendous promotion of catalytic activity for the hydrogenation of furan derivatives at ambient temperature under visible light irradiation.