Phosphate is an important fertilizer in agriculture and electrochemical sensors based on cobalt (Co) are promising for measurement of phosphate. The deposition of Co onto conductive substrates to form a nano/microstructured Co layer with rich active sites is a typical strategy to improve detection performances. However, the widely used substrates show smooth surfaces, which cannot provide extra active sites. Herein, a high‐performance phosphate sensor is fabricated by generating Co nanoparticles (NPs) on a hierarchically porous laser‐induced graphene (LIG) matrix with a large surface area. Specifically, a Co layer is first electroplated on the LIG matrix. Nevertheless, the pores of LIG will be blocked by the dense Co layer so the performances of the fabricated LIG‐Co sensor exhibit limited enhancements. Therefore, a “nearly all etching (NAE)” technique is developed to transform the dense Co layer to dispersive Co NPs and re‐expose the pores of LIG, both increasing the active sites. Compared to the LIG‐Co sensor, the LIG‐Co NP sensor displays overall superiority. The response time, sensitivity, and linearity are enhanced from ≈60 to ≈10 s, from 0.012 to 0.069 V dec−1, and from 0.973 to 0.998, respectively. The LIG‐Co NP sensor also shows a decent anti‐interference capability.

中文翻译：

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基于分层多孔激光诱导石墨烯上电镀钴纳米颗粒的高性能磷酸盐电位传感器

磷酸盐是农业中重要的肥料，基于钴 (Co) 的电化学传感器有望用于磷酸盐的测量。将Co沉积到导电基底上形成具有丰富活性位点的纳米/微米结构Co层是提高检测性能的典型策略。然而，广泛使用的基底显示出光滑的表面，不能提供额外的活性位点。在此，通过在具有大表面积的分层多孔激光诱导石墨烯（LIG）基质上生成钴纳米颗粒（NP）来制造高性能磷酸盐传感器。具体地，首先在LIG基体上电镀Co层。然而，LIG 的孔隙将被致密的 Co 层堵塞，因此所制造的 LIG-Co 传感器的性能增强有限。因此，开发了一种“几乎全蚀刻（NAE）”技术，将致密的Co层转变为分散的Co纳米颗粒，并重新暴露LIG的孔隙，两者都增加了活性位点。与LIG-Co传感器相比，LIG-Co NP传感器表现出整体优势。响应时间、灵敏度和线性度从约 60 秒增强至约 10 秒，从 0.012 V dec 增强至 0.069 V−1、 和 分别从 0.973 到 0.998。 LIG-Co NP传感器还表现出良好的抗干扰能力。