Visible-light driven Gd2Ti2O7/GdCrO3 composite for hydrogen evolution

Abstract

A series of Gd(2)Ti(2)O(7)/GdCrO(3) composites are prepared by solid state combustion method using Gd(NO(3))(3), TiO(2), Cr(2)O(3) as metal source and urea as a fuel. The composites are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-visible diffuse reflectance spectra (DRUV-vis), Brunauer-Emmett-Teller (BET) surface area measurements, photoluminescence spectra (PL), X-ray photoelectron spectroscopic (XPS) studies, photocurrent measurements etc. The photocatalytic activity of the composites is examined towards hydrogen production without using any co-catalyst under visible light illumination. The rate of formation of hydrogen is measured by the photocatalytic activity measurement device and gas chromatography (GC). The highest efficiency is observed over the composite GTC (Cr:Gd:Ti = 1:1:1). On the basis of photocurrent measurements and PL, a mechanism for the enhanced photocatalytic activity has been discussed.

Magnetic and magnetocaloric properties of HoCrO3 tuned by selective rare-earth doping

“…Both Tm and Gd doping is found to lower the E g of HCO sample. Clearly, E g of HGCO sample is smaller than that of HCO sample but slightly larger than that of the GdCrO 3 sample (2.7 eV) [44], i.e. in between the two end members, corroborating the doping/substitution effect.…”

In2O3/Bi2Sn2O7 heterostructured nanoparticles with enhanced photocatalytic activity

“…Herein, n is a constant depending on the type of transition in a semiconductor, e.g., n=1/2 for direct transition and n=2 for indirect transition [33]. Both Bi 2 Sn 2 O 7 and In 2 O 3 have a value of n=2, suggesting that the optical transition of these two semiconductors is indirect [23,27].…”

Preparation and photocatalytic activities of two new Zn-doped SrTiO3 and BaTiO3 photocatalysts for hydrogen production from water without cocatalysts loading

“…But they are approximate to those of the photocatalysts without cocatalysts loading, such as the recent reported photocatalysts of BaZr 1Àx Sn x O 3 (about 138 mmol h À1 for H 2 production) [37], (Ga 1Àx Zn x )(N 1Àx O x ) (about 300 mmol h À1 for H 2 production) [31] and Gd 2 Ti 2 O 7 /GdCrO 3 (about 200 mmol h À1 for H 2 production) [50]. So the present photocatalysts have potential application in hydrogen production.…”