Platinum Cocatalyst Loaded on Calcium Titanate Photocatalyst for Water Splitting in a Flow of Water Vapor

Abstract

In water splitting by using heterogeneous photocatalysts, the use of a suitable cocatalyst has been recognized as one of the key factors in enhancing the photocatalytic activity. Although platinum is a representative cocatalyst for many heterogeneous photocatalytic reactions, it has not been used for photocatalytic water splitting, owing to its high catalytic activity for the reverse reaction of water splitting. In the present study, platinum nanoparticles were loaded as a cocatalyst on a calcium titanate photocatalyst by a conventional impregnation method and a photodeposition method and examined for photocatalytic water splitting in a flow of water vapor. Platinum nanoparticles loaded by the impregnation method were found to retain the oxidized form on the calcium titanate photocatalyst, even under photoirradiation, and promoted hydrogen and oxygen production by photocatalytic water vapor splitting without promoting the reverse reaction.

Enhanced photocatalytic hydrogen evolution from water splitting by Z‐scheme CdS / BiFeO 3 heterojunction without using sacrificial agent

“…But it seems that the best method is to use at least two photocatalysts in different forms such as cocatalyst, doping the catalyst, and use of heterojunction structure. Noble metals such as platinum, nickel, silver, gold, and ruthenium have been used as co‐catalysts with semiconductors such as TiO 2 , 7‐10 CaTiO 3 , 11 CdS, 12,13 and g‐CN 14 . In doping, an impurity, metal or non‐metal, enters the photocatalytic structure and changes its optical properties.…”

Simultaneous Formation of CO and H2O2 from CO2 and H2O with a Ag–MnOx/CaTiO3 Photocatalyst

“…Calcium titanate (CaTiO 3 ) would be a suitable photocatalytic material for the assessment of the possibility of this new reaction system (eq 7), since it has been reported as a photocatalyst for water splitting, 22,23 CO 2 reduction, 5,24 and so on. 25 In this study for the first time, we found that a CaTiO 3 (CTO) photocatalyst loaded with a silver−manganese oxide (Ag−MnO x ) dual cocatalyst enabled the simultaneous production of CO and H 2 O 2 from CO 2 and H 2 O without the application of any external bias and consumption of any compounds, which is referred to as a Ag−MnO x /CTO photocatalyst.…”

Interplay between Mesocrystals of CaTiO3 and Edge Sulfur Atom Enriched MoS2 on Reduced Graphene Oxide Nanosheets: Enhanced Photocatalytic Performance under Sunlight Irradiation

“…Particularly, the alkaline‐earth metal perovskite oxides are of great scientific interest for inventive applications owing to their remarkable merits like high chemical and photostability, low cost, earth‐abundant constituents, non‐toxic nature, favorable conduction band (CB) (above −0.1 eV) and valence band (VB) (below +2.0 eV) potential, etc . As a prototype, calcium titanate (CaTiO 3 ) with orthorhombic crystal structure has attracted growing attention in the field of photocatalysis …”