To date, fabricating high sensitive, stable and facile sensing strategy for detection of nitrophenol still remains a challenge in practical applications. This article demonstrates for the first time a facile and stable colorimetric sensor based on three-dimensional graphene/mesoporous Fe₃O₄ (3D GF/m-Fe₃O₄) heterogeneous nanozyme. Using a simple hydrothermal procedure, mesoporous Fe₃O₄ nanoparticles were in situ synthesized on 3D GF. The 3D GF/m-Fe₃O₄ nanohybrid possesses high peroxidase mimicking activity due to the synergistic effect of 3D GF and m-Fe₃O₄. Based on the peroxidase-like activity and p-nitrophenol-mediated inhibition controllability, the nanohybrid was successfully adopted in the sensitive and selective sensing detections of p-nitrophenol (PNP) with a low detection limit of 45 nM. Moreover, 3D GF/m-Fe₃O₄ nanohybrid shows to be extremely robust, as it still retains its original response to PNP after being reused for 10 times. The method was applied to the determination of PNP in spiked lake water and gave good recoveries. With the merits of high sensitivity and selectivity, simplification, recyclability, and excellent stability, this sensing platform not only expands the application of 3D GF and Fe₃O₄, but also provides an alternative technique to construct robust nanozyme with multiple functionalities for various biological and environmental applications.

迄今为止，在实际应用中，制造用于检测硝基苯酚的高灵敏，稳定和简便的检测策略仍然是一个挑战。本文首次展示了一种基于三维石墨烯/介孔Fe ₃ O ₄（3D GF / m-Fe ₃ O ₄）异质纳米酶的简便且稳定的比色传感器。使用简单的水热程序，在3D GF上原位合成了介孔Fe ₃ O ₄纳米粒子。3D GF / m-Fe ₃ O ₄纳米杂化物由于3D GF和m-Fe ₃ O ₄的协同作用而具有高的过氧化物酶模拟活性。。基于过氧化物酶样活性和对硝基苯酚介导的抑制可控性，该纳米杂交体已成功用于对硝基苯酚（PNP）的灵敏和选择性感测，检测限低至45 nM。此外，3D GF / m-Fe ₃ O ₄纳米杂化物表现出极强的耐用性，因为它在重复使用10次后仍保留了其对PNP的原始响应。该方法用于加标湖水中PNP的测定，回收率高。凭借高灵敏度和选择性，简化，可回收性以及出色的稳定性等优点，该传感平台不仅扩展了3D GF和Fe ₃ O _4的应用，但也提供了一种替代技术，可构建具有多种功能的健壮纳米酶，用于各种生物学和环境应用。