LED-driven continuous flow carbon dioxide hydrogenation on a nickel-based catalyst

LED-driven controlled deposition of Ni onto TiO2 for visible-light expanded conversion of carbon dioxide into C1–C2 alkanes

“…It is interesting to note that XPS signals corresponding to the Ni 2p levels were rather complex, being deconvoluted in up to three Gaussian/Lorentzian peaks (see SI file, Table S2 and Figure S1). This situation is typically found in the presence of multiplet contributions and satellite structures, whose formation could be found in recent papers [50,65]. For Ni 2+ the satellite at about +6.0 eV might be assigned to a final state effect associated with a (core) 3d 8 L configuration (where L stands for ligands).…”

“… 57 The signal centered at T IV ∼ 550 °C was assigned to the reduction of smaller NiO nanoparticles dispersed in the TiO 2 substrate with a very strong interaction. 50,58 A noticeable decrease in the signal intensities was observed for the Ni/TiO 2 -A, which was attributed to the partial reduction of the Ni-based particles and TiO 2 substrate after the thermal activation in a 10%-H 2 atmosphere. However, the appearance of a signal at T I ∼ 230 °C after the activation suggested the presence of NiO particles with a weak or null interaction with the support, 58 which is in agreement with the decrease in Ni loading observed by XPS ( Table 1 and Fig.…”

“…This was concluded after the detection of reduction peaks at T II ~330ºC and T III ~370 o C which were attributed to the reduction of NiO species with low and high interaction with the support, respectively [57]. The signal centered at T IV ~550 o C was assigned to the reduction of smaller NiO nanoparticles dispersed in the TiO 2 substrate with a very strong interaction [50,58]. A noticeable decrease in the signal intensities was observed for the Ni/TiO 2 -A, which was attributed to the partial reduction of the Ni-based particles and TiO 2 substrate after the thermal activation in 10%-H 2 atmosphere.…”

“…The UV-vis spectra showed very significant changes with respect to the absorption bands of TiO 2 P25 (Figure 2a), which displayed a strong absorption below 400 nm corresponding to the ground excitonic state of TiO 2 . The absorption bands of Ni/TiO 2 were expanded towards the visible-near infrared region resulting from the formation of either metallic Ni or NiO nanoparticles [42,50,51]. After thermal activation, the absorption in the visible region is greatly enhanced, due to the reducing conditions that led to the formation of oxygen vacancies, the incorporation of H-containing species or even Ti 3+ cations on the surface of TiO 2 [52,53].…”

Strong Interaction over Ru/Defects‐Rich Aluminium Oxide Boosts Photothermal CO2 Methanation via Microchannel Flow‐Type System

“…For further evaluating the photothermal catalytic performance of Ru‐Al 2 O 3‐x ‐L, the recently reported state‐of‐art photothermal catalysts sorted by reaction pressure, and the CH 4 yield was normalized to the mass of metal in Figure 6e and Table S4 (Supporting Information). After normalizing, the CH 4 yield of Ru‐Al 2 O 3‐x ‐L and Ru‐Al 2 O 3‐x ‐L channel catalyst was superior to the Ru@FL‐LDHs, [ 11 ] Ru‐Al 2 O 3 powder, [ 22 ] Rh‐Al 2 O 3 , [ 22 ] Ni/Nb 2 C, [ 53 ] Ni/Al 2 O 3 •SiO 2 , [ 66 ] RuO 2 /STO, [ 44 ] Pd/Nb 2 O 5 , [ 67 ] Ru‐Al 2 O 3 , [ 68 ] Ni(20)‐BTO, [ 25 ] and Rh/Al. [ 69 ] The efficient photo‐thermal conversion on the micro/nanostructures integrated Ru‐Al 2 O 3‐x ‐L catalyst and suitable design of the catalytic system enhanced the catalytic performance.…”