Nanostructured Co₃O₄ has novel properties, so it can be manufactured with simple, fast preparation of samples, and a low-cost process. FESEM field emission electron microscope scanning, XRD diffraction, and Raman spectroscopy characterized Co₃O${}_4$ nanostructured tetrahedral structures with multiple branches. Good sensitivity and selectivity and high stability can be seen for the nanostructured Co₃O₄. Cationic surfactant (CTAB) and anionic surfactant (PVP) both have a guiding effect on Co₃O₄ production. The self-assembled Co₃O₄ particles in Methylene Blue (MB) exhibit excellent Surface Enhanced Raman Spectroscopy efficiency. An average enhancement factor (EF) of 50 $\times$ 10⁶ was achieved for the Co₃O₄ in PVP on 135 gsm printing paper and 41 $\times 10^6$ for the Co₃O₄ in CTAB on 240 gsm printing paper.

The results showed Co₃O₄ in PVP produced the highest sensitivity, specificity, and the lowest limit of detection LOD which was 0.52 nM for MB as Raman reporter molecule, and the sensitivity offered almost 98% with selectivity equal to 92%. To the best of the author’s knowledge, this is the first demonstration of Co₃O₄ in PVP paper-based as a chemical sensor by enhanced Raman spectroscopy signal.

纳米结构的 Co ₃ O ₄具有新颖的特性，因此可以通过简单、快速的样品制备和低成本的工艺制造。FESEM 场发射电子显微镜扫描、XRD 衍射和拉曼光谱表征 Co ₃ O${}_4$具有多个分支的纳米结构四面体结构。纳米结构的Co ₃ O ₄具有良好的灵敏度和选择性以及高稳定性。阳离子表面活性剂（CTAB）和阴离子表面活性剂（PVP）都对Co ₃ O _{4 的}生产有指导作用。亚甲蓝 (MB) 中的自组装 Co ₃ O ₄颗粒表现出优异的表面增强拉曼光谱效率。平均增强因子 (EF) 为 50$\times$135 gsm 打印纸上的 PVP 中的 Co ₃ O ₄达到了10 ⁶和 41$\times 10^6$用于240 gsm 打印纸上 CTAB 中的 Co ₃ O ₄。

结果表明，PVP中的Co ₃ O ₄产生最高的灵敏度、特异性和最低检测限LOD，MB作为拉曼报告分子为0.52 nM，灵敏度接近98%，选择性等于92%。据作者所知，这是第一次通过增强拉曼光谱信号证明PVP 纸基中的 Co ₃ O ₄作为化学传感器。