Preparation of Cr-doped Ba4In2O7/In2O3 nanocomposite and its photo-assisted chargeability in hydrogen storage alloy/photocatalyst electrode

Homogeneously mixed Cr-doped Ba4In2O7/In2O3 nanocomposite (Cr–BIO) was synthesized by a simple sol–gel method. The Cr–BIO powder was characterized by thermogravimetric (TG), X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV–vis diffuse reflectance spectrometry. The as-prepared Cr–BIO powder shows the morphology comprised of Cr-doped Ba4In2O7 nanorods and Cr-doped In2O3 nanoparticles and a wide light absorption range with a main absorption edge around 480 nm. The hydrogen storage alloy/Cr–BIO photoelectrode was then fabricated and the photo-assisted electrochemical behavior was investigated by charge–discharge tests. The electrode exhibited obvious photo-assisted chargeable properties in KOH aqueous solution as the discharge time increased remarkably under the xenon light irradiation. The photo-assisted chargeability of HSA/Cr–BIO electrode was then discussed.