La1−xSrxCo1−yFeyO3−δ perovskites: Preparation, characterization and solar photocatalytic activity

• LaCoO3 perovskites doped by Sr and/or Fe (La1−xSrxCo1−yFeyO3−δ) have been prepared.
• La1−xSrxCo1−yFeyO3−δ show solar photocatalytic activity for 2-propanol degradation.
• The photoreactivity is influenced by the presence of Sr and/or Fe.
• Sr increases the oxygen lattice defects in the perovskites lowering the band gap energy value.
• The sample La0.6Sr0.4CoO3−δ shows the best catalytic activity.

LaCoO3 perovskites substituted by Sr at the A site and/or by Fe at the B site have been prepared by the citrate method. Characterizations by several techniques, such as specific surface area (BET method), XRD, TPR, SEM, UV–vis in DRS mode, XPS and TGA analyses, have been performed.The so prepared La1−xSrxCo1−yFeyO3−δ perovskites are semiconductor materials showing band gap energy values from 1.9 to 3.2 eV. They displayed solar photocatalytic activity for the 2-propanol degradation in gas–solid regime. The photocatalytic results suggest that the perovskites containing Fe are less active and the activity decreases by increasing the Fe content, however the presence of iron avoids the catalyst deactivation. The best photocatalytic activity in the 2-propanol degradation was found for the sample La0.6Sr0.4CoO3−δ.

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