Comparing Pt/SrTiO3 to Rh/SrTiO3 for hydrogen photocatalytic production from ethanol

Abstract

Photocatalytic hydrogen production from ethanol as an example of biofuel is studied over 0.5 wt% Rh/ SrTiO 3 and 0.5 wt% Pt/SrTiO 3 perovskite materials. The rate of hydrogen production, r H2 , over Pt/SrTiO 3 is found to be far higher than that observed over Rh/SrTiO 3 (4 9 10 -6 mol of H 2 g catal.-1 min -1 (1.1 9 10 -6 mol of H 2 m catal.-2 min -1 ) compared to 0.7 9 10 -6 mol of H 2 g catal.-1 min -1 (5.5 9 10 -8 mol of H 2 m catal.-2 min -1 ), respectively, under UV excitation with a flux equivalent to that from the sun light (ca. 1 mW cm -2 ). Analyses of the XPS Rh3d and XPS Pt4f indicate that Rh is mainly present in its ionic form (Rh 3? ) while Pt is mainly present in its metallic form (Pt 0 ). A fraction of the non-metallic state of Rh in the catalyst persisted even after argon ion sputtering. The tendency of Rh to be oxidized compared to Pt might be the reason behind the lower activity of the former compared to the later. On the contrary, a larger amount of methane are formed on the Rh containing catalyst compared to that observed on the Pt containing catalyst due to the capacity of Rh to break the carbon-carbon bond of the organic compound.

Superior performance of Ni–W–Ce mixed-metal oxide catalysts for ethanol steam reforming: Synergistic effects of W- and Ni-dopants

“…Thus, doping of ceria with Ni or W could induce substantial electronic and structural perturbations in the host oxide. Our studies point to synergistic effects when Ni and W are confined inside ceria; effects which make the performance of Ni/Ni x W y Ce 1-x-y O 2 catalysts as good or better than that of catalysts containing expensive noble metals such as Rh and Pt [7,[10][11][12]. This synergistic effect between Ni and W can be important in several areas of chemistry and material sciences in which ceria is widely used [13,14].…”

NiS Protective Layer for Repelling Chloride Ion Effectively for Water Oxidation on Photocatalytic Seawater Splitting

“…In the Ti spectrum (Figure 3c), two peaks at 459.06 and 465.11 eV were assigned to Ti 2p 3/2 and Ti 2p 1/2 . 26,27 showing that Ti existed in the form of tetravalent. In the O spectrum (Figure 3d), the peak at 530.43 eV was attributed to surface lattice oxygen (O latt ) in cubic SrTiO 3 and the peak at 529.08. eV was attributed to oxygen in cocatalyst Co 3 O 4 , where 532.22 eV was attributed to the absorbed H 2 O.…”

Reduced Graphene Oxide / Strontium Titanate—Investigation of Improved Photoactivity

“…[10] Its photocatalytic activity and durability can be improved by various approaches described in the literature, e.g. metal doping, [12,13] surface modi cations with organic sensitizers, [14] modi cation with metallic co-catalyst [15] or formation of heterojunctions and composites. [9,16] Surface modi cation by coupling of metal oxides with graphene family compounds e.g.…”