Enhanced catalytic activity of Fe bimetallic modified PAN fiber complexes prepared with different assisted metal ions for degradation of organic dye

Two transition metal ions (Cu2+ and Co2+) and two rare earth metal ions (Ce3+ and La3+) were used as the assisted metal ions, respectively to prepare the transition metal and rare metal assisted Fe bimetallic amidoximated polyacrylonitrile (AO-PAN) fiber complexes. And their coordination configuration and visible light adsorption properties were examined by coordination number determination and UV–vis–DRS. Then the catalytic performance of these complexes was evaluated as the heterogeneous Fenton catalysts in Rhodamine B degradation by changing the nature and dosage of the assisted ions added. The results indicated that the incorporation of the assisted metal ions led to Fe bimetallic AO-PAN complexes with the more unsaturated configurations than Fe monometallic AO-PAN complex due to the changes in their coordination numbers. The visible light adsorption properties of Cu–Fe or Ce–Fe AO-PAN bimetallic complexes varied significantly with their Cu/Fe or Ce/Fe molar ratio. Fe bimetallic AO-PAN complex showed a higher catalytic performance as the Fenton catalysts toward the dye degradation than Fe monometallic AO-PAN complex. And the nature and dosage of the assisted metal ions can affect their catalytic activities. Ce–Fe bimetallic AO-PAN complex was found to have a better stability in a wider pH range than Cu–Fe bimetallic AO-PAN complex.

Graphical abstract.Figure optionsDownload full-size imageDownload high-quality image (167 K)Download as PowerPoint slideHighlights► Fe modified PAN fiber complexes are optimized with assisted metal ions. The complexes are used as the effective heterogeneous Fenton catalysts. ► Addition of Cu2+ or Ce3+ ions increases the catalytic ability of these complexes. ► Ce–Fe bimetallic catalyst shows a higher stability in a wider pH range. ► Assisted metal ions are not favorable for visible light adsorption of the catalysts.