Comparative study on photocatalytic efficiency of Mg doped CuFeO2 versus TiO2 doped CuFeO2 delafossite based on their application for the removal of tartrazine yellow dye

The present work highlights the comparative analysis between Mg doped CuFeO 2 (named as Mg-CFO) and TiO 2 /CuFeO 2 composite (named as TiO 2 -CFO) for the photodegradation of TZ dye in aqueous solution. Physicochemical tests like XRD, FTIR, FESEM, EDX was done for both the composites. The pH pzc values of Mg-CFO and TiO 2 -CFO were determined to be 9.34 and 9.0 respectively for which both photocatalysts gave good removal efficiency of anionic TZ in an acidic or lower pH region. Mg-CFO degraded 87 ​% of 20 ​mg ​L −1 of TZ in 100 ​mL of solution at 50 ​mg dosage, under pH∼2, at 130 ​rpm and 30 ​°C temperature showing a rate constant of 0.00602 min −1 and TiO 2 -CFO degraded 91 ​% of TZ dye under the same conditions showing a rate constant of 0.00637 min −1 . The quenching test showed that both photocatalysts had generated O 2 °- radicals as the primary species and OH ° as the secondary species. In general, TiO 2 -CFO composite was proved to be a comparatively better photocatalyst than Mg-CFO sample. • Mg doped CuFeO 2 and TiO 2 /CuFeO 2 composite and its application. • Facile hydrothermal method was used to synthesize Mg doped CuFeO 2 and TiO 2 /CuFeO 2 composite. • TiO 2 –CuFeO 2 had the lowest charge recombination tendency in comparison to Mg doped CuFeO 2 . • TiO 2 –CuFeO 2 composite degraded 95.7 ​% of 10 ​mg ​L −1 of TZ dye. • Mg doped CuFeO 2 degraded 90.5 ​% of 10 ​mg ​L −1 of TZ dye. • TiO 2 –CuFeO 2 composite can behave either as a type II p-n heterojunction or a Z scheme heterojunction.