铁酸锌纳米纤维载银的制备及催化还原对硝基苯酚

Preparation of Silver-Loaded Zinc Ferrate Nanofibers and Catalytic Reduction of P-Nitrophenol

摘要: 利用室温还原法将废水中的毒性较高的对硝基苯酚(4-NP)转换为对氨基苯酚(4-AP)具有重要意义。本文利用超长一维结构的铁酸锌纳米纤维(ZnFe₂O₄ NFs)为载体，采用原位还原法负载Ag纳米粒子，其负载量约为6.16%。实验表明，ZnFe₂O₄/Ag NFs在10 min内催化4-NP还原为4-AP，其转化率为85.25%。根据反应动力学曲线获得ZnFe₂O₄/Ag NFs的动力学速率常数k_app为0.196 min⁻¹。这种优异的性能正是由于Ag具有更高的功函数，能够与ZnFe₂O₄形成异质结构，有效促进界面电子快速转移到半导体ZnFe₂O₄，进一步将4-NP还原成4-AP，有效提高了催化剂的催化活性。此外，ZnFe₂O₄ NFs的特殊结构也使其具有良好的循环稳定性，制备的ZnFe₂O₄/Ag NFs在3次循环使用后经过14 min对4-NP的还原率依然可以达到93.59%，这种循环使用性能良好且性能优异的一维结构催化剂有望在有机染料等污染物处理等领域表现出优异的潜力。

Abstract: It is of great significance to convert the highly toxic p-nitrophenol (4-NP) in wastewater into p-aminophenol (4-AP) by the room-temperature reduction method. In this paper, ultra-long one-dimensional structured zinc ferrate nanofibers (ZnFe₂O₄ NFs) were used as carriers, and Ag nanoparticles were loaded by in-situ reduction method, with a loading capacity of approximately 6.16%. Experiments show that ZnFe₂O₄/Ag NFs catalyzes the reduction of 4-NP to 4-AP within 10 minutes, with a conversion rate of 85.25%. The kinetic rate constant k_app of ZnFe₂O₄/Ag NFs was obtained as 0.196 min⁻¹ based on the reaction kinetics curve. This outstanding performance is attributed to the fact that Ag has a higher work function, which can form a heterostructure with ZnFe₂O₄, effectively promoting the rapid transfer of interfacial electrons to semiconductor ZnFe₂O₄, further reducing 4-NP to 4-AP, and effectively enhancing the catalytic activity of the catalyst. In addition, the special structure of ZnFe₂O₄ NFs also endows it with good cycling stability. The prepared ZnFe₂O₄/Ag NFs still achieved a reduction rate of 93.59% for 4-NP after 14 minutes of three cycles of use. This one-dimensional structure catalyst with good and excellent cycling performance is expected to show outstanding potential in the treatment of pollutants such as organic dyes and other fields.