Effective fabrication of cellulose nanofibrils supported Pd nanoparticles as a novel nanozyme with peroxidase and oxidase-like activities for efficient dye degradation
Effective fabrication of cellulose nanofibrils supported Pd nanoparticles as a novel nanozyme with peroxidase and oxidase-like activities for efficient dye degradation
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DOI：
10.1016/j.jhazmat.2022.129165
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发表时间：
2022-05-30
影响因子：
13.6
通讯作者：
Lee, Seung-Hwan
中科院分区：
文献类型：
--
作者：
Dadigala, Ramakrishna;Bandi, Rajkumar;Lee, Seung-Hwan
基于纳米酶的染料降解方法在水污染修复中具有广阔的应用前景。虽然钯纳米粒子（PdNPs）是已知的作为纳米酶，他们的染料降解能力还没有被调查。纳米酶活性低、容易聚集、回收和再利用困难是实现这一目标的主要挑战。首次将纤维素纳米纤维负载的PdNPs（PdNPs/PCNF）作为一种新型的纳米酶用于染料降解，该酶具有良好的过氧化物酶和氧化酶模拟活性，且易于回收利用。通过调节pH值和微波辐射，建立了一种高效、快速制备PdNPs/PCNF的方法。酶动力学研究表明，良好的动力学参数和过氧化物酶和氧化酶分别为415和277 U/g的比活性。PdNPs/PCNF在0.4M H2 O2（pH5.0）作用下12 min（0.468 min（-1））内对亚甲基蓝的降解率达99.64%。机制研究表明，参与羟基和超氧自由基。利用PCNF的网状结构，制备了PCNF膜和泡沫，比较了它们对染料的降解能力，并测试了它们的回收性能。成功地降解混合染料溶液和加标真实的水样，实现了连续流动的方法，证明了使用泡沫填充柱。
Nanozyme-based dye degradation methods are promising for the remediation of water pollution. Though Pd nanoparticles (PdNPs) are known to act as nanozymes, their dye degradation capability has not been investigated. Low nanozyme activities, easy aggregation, difficulties in recovery and reuse are the major challenges in achieving this. For the first time, cellulose nanofibrils-supported PdNPs (PdNPs/PCNF) as a novel nanozyme with good peroxidase and oxidase-mimicking activities and easy recyclability is explored for dye degradation. An efficient and rapid method of PdNPs/PCNF preparation was demonstrated by adjusting the pH and microwave irradiation. Enzyme kinetic studies revealed good kinetic parameters and specific activities of 415 and 277 U/g for peroxidase and oxidase, respectively. PdNPs/PCNF offered 99.64% degradation of methylene blue within 12 min (0.468 min(-1)) with 0.4 M H2O2 at pH 5.0. Mechanistic studies revealed the involvement of hydroxyl and superoxide radicals. Owing to the network-like structure of PCNF, films and foams were prepared, their dye degradation potentials were compared, and recyclability was tested. Successful degradation of mixed dye solutions and spiked real water samples was achieved and a continuous flow method was demonstrated using a foam-packed column.