Light-Assisted Semi-Hydrogenation of 1,3-Butadiene with Water.

Sustainable processes for semi-hydrogenation of alkynes/alkadienes impurities in alkenes feedstocks are in great demand in industry as the utilization of excessive hydrogen, high temperature and unsatisfactory alkenes selectivity of the current thermo-catalytic route, however, their development is still challenging. Herein, we innovate a light-assisted semi-hydrogenation process in gas-feed fixed bed reactor, with water as hydrogen atom source by in situ photocatalysis. Using Pd/TiO2 as model catalyst, this process shows an excellent catalytic performance for the semi-hydrogenation of 1,3-butadiene, with 100 % of butenes selectivity at ≈99 % of conversion over 180 h of reaction at ambient temperature driven by 66 mW cm-2 of irradiation intensity. This light-driven, H2 -free, ambient temperature semi-hydrogenation process, with superior performance to that of thermocatalytic route, shows attractive to bring an evolution in industrial hydrogenation technology to an economical and safe way.

One-Dimensional P-Doped Graphitic Carbon Nitride Tube: Facile Synthesis, Effect of Doping Concentration, and Enhanced Mechanism for Photocatalytic Hydrogen Evolution.

P-doped graphitic carbon nitride tubes (P-CNTS) with different P concentrations were successfully fabricated via a pre-hydrothermal in combination with a calcination process under a nitrogen atmosphere. The as-prepared samples exhibited excellent photocatalytic performance with a hydrogen production rate (HPR) of 2749.3 µmol g-1 h-1, which was 17.5 and 6.6 times higher than that of the bulk graphitic carbon nitride (CNB) and graphitic carbon nitride tube (CNT). The structural and textural properties of the P-CNT samples were well-investigated via a series of characterization methods. Compared with the bulk g-C3N4, the tubular structure of the doped samples was provided with a larger specific surface area (SSA) and a relatively rough interior. Besides the above, surface defects were formed due to the doping, which could act as more active sites for the hydrogen production reaction. In addition, the introduction of the P element could effectively adjust the band-gap, strengthen the harvest of visible-light, and boost the effective separation of photogenerated charges. More interestingly, these findings can open up a novel prospect for the enhancement of the photocatalytic performance of the modified g-C3N4.