A three-dimensional (3D) network nanocomposite is constructed by electrospinning tin dioxide nanofibers (SnO₂ NFs) on the surface of indium tin oxide (ITO) and then in-situ electrodepositing gold nanoparticles (AuNPs). With the aid of large surface area of SnO₂ NFs and the surface plasmon resonance (SPR) effect of AuNPs, the novel 3D architecture is beneficial to the mass transfer and the separation efficiency of photogenerated electrons and holes. In the presence of photosensitizer of Ru(bpy)₃²⁺ (tris (2,2'-bipyridyl) dichlororuthenium (II) hexahydrate (Ru(bpy)₃(PF₆)₂), the ITO/SnO₂-AuNPs electrode shows good photoelectrochemical (PEC) response to nitrite (NO₂-) under visible light irradiation. The linear range for NO₂- determination is from 10^-9 to 10^-5 M with a low detection limit of 4.8 × 10^-10 M. The ITO/SnO₂-AuNPs photoanode based PEC sensor is also successfully applied to analyze trace NO₂- in human urine, showing excellent anti-interference and stability. This work may pave the way for designing noble metal-semiconductor heterogeneous materials with tailored properties for the field of biosensor design.

通过将二氧化锡纳米纤维（SnO ₂ NFs）静电纺丝在氧化铟锡（ITO）的表面上，然后原位电沉积金纳米颗粒（AuNPs），来构建三维（3D）网络纳米复合材料。借助SnO ₂ NFs的大表面积和AuNPs的表面等离振子共振（SPR）效应，新颖的3D结构有利于光生电子和空穴的传质和分离效率。在Ru（bpy）₃ ²⁺（三（2,2'-联吡啶基）二氯钌（II）六水合物（Ru（bpy）₃（PF ₆）₂））的光敏剂存在下，ITO / SnO ₂-AuNPs电极在可见光照射下对亚硝酸盐（NO _2-）表现出良好的光电化学（PEC）响应。的线性范围为NO ₂ -判定为10 ^-9〜10 ^-5米，4.8×10的低检测限^-10 M的ITO /的SnO ₂光电阳极基于PEC传感器也成功地应用于分析痕量NO -AuNPs _2-在人体尿液中，表现出优异的抗干扰性和稳定性。这项工作可能为设计具有生物传感器设计领域定制性质的贵金属-半导体异质材料铺平道路。