Abstract Cobalt doped magnetically separable Zn1-xCoxFeMnO4 (x = 0.0, 0.25, 0.50, 0.75, 1.0) nanoparticles of ferrite were synthesized using auto-combustion process of sol-gel utilizing glycine as a fuel. The powder XRD and Rietveld refinement studies showed that all of the samples developed a single-phase cubic spinel system. The morphological investigations demonstrate the sphere-like nanostructures, which get distorted after an increase in the concentration of cobalt. A transformation from superparamagnetic activity to ferrimagnetic character has been reported with the introduction of Co2+. As synthesized ferrite nanoparticles have demonstrated an improvement in coercivity with lower density magnetization with reduced crystallite size. A rise in the remanence ratio were observed with the Co2+ content. The optical characterization shows a blue shift in the band gap with increase of Co2+. Considering the band structure in the visible region, the photocatalytic activity of as-synthesized Zn1-xCoxFeMnO4 photocatalysts for degradation of methylene blue under natural sunlight was investigated. The Zn0.25Co0.75MnFeO4 ferrite demonstrated more than 99% degradation of MB dye within 20 min. The effect of catalyst loading, pH, and stability of photocatalyst were studied.

中文翻译：

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磁性可分离Zn1-xCoxFeMnO4纳米铁​​氧体的合成与表征作为高效光催化剂在太阳光照射下降解染料

摘要 以甘氨酸为燃料，采用溶胶-凝胶自燃法合成了钴掺杂磁性可分离Zn1-xCoxFeMnO4 (x = 0.0, 0.25, 0.50, 0.75, 1.0)铁氧体纳米颗粒。粉末 XRD 和 Rietveld 精修研究表明，所有样品都形成了单相立方尖晶石系统。形态学研究表明，球状纳米结构在钴浓度增加后会发生扭曲。据报道，随着 Co2+ 的引入，从超顺磁性活动到亚铁磁性特征的转变。由于合成的铁氧体纳米颗粒已证明矫顽力提高，磁化密度降低，微晶尺寸减小。随着 Co2+ 含量的增加，观察到剩磁比升高。光学表征显示，随着 Co2+ 的增加，带隙发生蓝移。考虑到可见光区的能带结构，研究了合成的 Zn1-xCoxFeMnO4 光催化剂在自然阳光下降解亚甲基蓝的光催化活性。Zn0.25Co0.75MnFeO4 铁氧体证明 MB 染料在 20 分钟内降解超过 99%。研究了催化剂负载量、pH值和光催化剂稳定性的影响。