华中师范大学朱成周团队研报道了混合塑料试验中Fe-Se二元催化剂的羟基溢出效应。相关研究成果于2024年12月24日发表在《美国化学会杂志》。

真实塑料废物的复杂成分对其大规模处置构成了重大挑战。塑料的响应性现场成分分析在选择下游加工方法时具有参考价值。基于纳米催化剂的检测试剂盒非常适合这一场景；然而，由于其高度惰性的化学性质，目前还没有有效的塑料纳米催化剂。

该文中，研究人员首次揭示了铁硒双中心催化剂（FeSe/NC）中的羟基溢出效应，并设计了一种用于混合塑料的原型比色分析试剂盒。实验和理论结果表明，铁位点是H₂O₂活化的主要活性位点，产生吸附的羟基（*OH）中间体，随后作为羟基自由基（OH）解吸并转移到硒位点、载体甚至塑料上进行进一步催化。

具体来说，转移到不同塑料中的OH显示出不同的活性，其中信号输出被用作塑料识别的指纹。此外，剩余的*OH可以对样品中的氧化还原干扰做出反应，以提高准确性。与涉及精密仪器和复杂预处理的传统技术相比，该方法能够以超低的成本（0.0012美元）快速测定（～10分钟）未经处理的粉末状混合塑料废物。

研究发现填补了塑料分析中的一个关键空白，为应对全球塑料废物危机的各种升级和回收策略提供了新的技术指导。

附：英文原文

Title: Hydroxyl Spillover in Fe–Se Dual-Site Catalysts for Mixed Plastics Assay

Author: Yu Wu, Wenxuan Jiang, Weiqing Xu, Fan Lv, Shaojia Song, Liuyong Hu, Canglong Wang, Lirong Zheng, Wenling Gu, Riguang Zhang, Shaojun Guo, Chengzhou Zhu

Issue&Volume: December 24, 2024

Abstract: The complex composition of real plastic wastes poses a significant challenge for their large-scale disposal. A responsive on-site compositional analysis of plastics is informative in choosing downstream processing methods. Nanocatalyst-based assay kit is highly qualified for this scene; however, there remain no efficient nanocatalysts for plastics due to their highly inert chemistry. Herein, we first unveiled the hydroxyl spillover effect in an Fe–Se dual-site catalyst (FeSe/NC) and devised a prototype colorimetric assay kit for mixed plastics. Experimental and theoretical results unveiled that Fe sites acted as the main active sites for H2O2 activation to produce adsorbed hydroxyl (*OH) intermediates, which subsequently desorb as hydroxyl radicals (OH) and transfer to Se sites, supports, and even plastics for further catalysis. Specifically, OH transferred to different plastics shows varying activities, where signal outputs were hereby used as the fingerprint for plastic identification. Moreover, the remaining *OH could respond to redox interferences in the samples for enhanced accuracy. In contrast to traditional techniques involving precise apparatus and complex pretreatments, our approach enables a rapid assay (～10 min) of raw powdery mixed plastic wastes with an ultralow cost (0.0012 $). This discovery fills a crucial gap in the plastic assay, offering new technical guidance for diverse upcycling and recycling strategies to tackle the global plastic waste crisis.

DOI: 10.1021/jacs.4c16655

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c16655