Enhanced, robust light-driven H2 generation by gallium-doped titania nanoparticles.

Title	Enhanced, robust light-driven H2 generation by gallium-doped titania nanoparticles.
Authors	S. Luo; T.D. Nguyen-Phan; D. Vovchok; I. Waluyo; R.M. Palomino; A.D. Gamalski; L. Barrio; W. Xu; D.E. Polyansky; J.A. Rodriguez; S.D. Senanayake
Journal	Phys Chem Chem Phys
DOI	10.1039/c7cp04155a
Abstract	The splitting of water into molecular hydrogen and oxygen with the use of renewable solar energy is considered one of the most promising routes to yield sustainable fuel. Herein, we report the H2 evolution performance of gallium doped TiO2 photocatalysts with varying degrees of Ga dopant. The gallium(iii) ions induced significant changes in the structural, textural and electronic properties of TiO2 nanoparticles, resulting in remarkably enhanced photocatalytic activity and good stability for H2 production. Ga3+ ions can act as hole traps that enable a large number of excited electrons to migrate towards the TiO2 surface, thereby facilitating electron transfer and charge separation. Additionally, the cationic dopant and its induced defects might introduce a mid-gap state, promoting electron migration and prolonging the lifetime of charge carrier pairs. We have discovered that the optimal Ga dopant concentration was 3.125 at% and that the incorporation of platinum (0.5 wt%) as a co-catalyst further improved the H2 evolution rate up to 5722 ?mol g-1 h-1. Pt not only acts as an electron sink, drastically increasing the electron/hole pair lifetime, but it also creates an intimate contact at the heterojunction between Pt and Ga-TiO2, thus improving the interfacial electron transfer process. These catalyst design strategies provide new ways of designing transition metal photocatalysts that improve green fuel production from renewable solar energy and water.
Citation	S. Luo; T.D. Nguyen-Phan; D. Vovchok; I. Waluyo; R.M. Palomino; A.D. Gamalski; L. Barrio; W. Xu; D.E. Polyansky; J.A. Rodriguez; S.D. Senanayake.Enhanced, robust light-driven H2 generation by gallium-doped titania nanoparticles.. Phys Chem Chem Phys. 2018. doi:10.1039/c7cp04155a

Related Elements

Gallium

31 Ga 69.723000000 Gallium

See more Gallium products. Gallium (atomic symbol: Ga, atomic number: 31) is a Block P, Group 13, Period 4 element with an atomic weight of 69.723.The number of electrons in each of Gallium's shells is 2, 8, 18, 3 and its electron configuration is [Ar] 3d¹⁰ 4s² 4p¹. The gallium atom has a radius of 122.1 pm and a Van der Waals radius of 187 pm. Gallium Bohr Model Gallium was predicted by Dmitri Mendeleev in 1871. It was first discovered and isolated by Lecoq de Boisbaudran in 1875. In its elemental form, gallium has a silvery appearance. Elemental Gallium Gallium is one of three elements that occur naturally as a liquid at room temperature, the other two being mercury and cesium. Gallium does not exist as a free element in nature and is sourced commercially from bauxite and sphalerite. Currently, gallium is used in semiconductor devices for microelectronics and optics. The element name originates from the Latin word 'Gallia' referring to Gaul, the old name of France.

Titanium

22 Ti 47.867000000 Titanium

See more Titanium products. Titanium (atomic symbol: Ti, atomic number: 22) is a Block D, Group 4, Period 4 element with an atomic weight of 47.867. The number of electrons in each of Titanium's shells is [2, 8, 10, 2] and its electron configuration is [Ar] 3d² 4s². Titanium Bohr Model The titanium atom has a radius of 147 pm and a Van der Waals radius of 187 pm. Titanium was discovered by William Gregor in 1791 and first isolated by Jöns Jakob Berzelius in 1825. In its elemental form, titanium has a silvery grey-white metallic appearance. Titanium's properties are chemically and physically similar to zirconium, both of which have the same number of valence electrons and are in the same group in the periodic table. Elemental Titanium Titanium has five naturally occurring isotopes: ⁴⁶Ti through ⁵⁰Ti, with ⁴⁸Ti being the most abundant (73.8%). Titanium is found in igneous rocks and the sediments derived from them. It is named after the word Titanos, which is Greek for Titans.