基于Pd-Ni/Si Nanowires电极室内甲醛实时监测处理装置

A Real-Time Monitoring and Processing System for Detecting Indoor Formaldehyde Based on Pd-Ni/Si Nanowires Electrode

研究设计一种室内甲醛气体实时监测和处理一体化装置。首先,通过电化学方法刻蚀大面积硅纳米线阵列并通过无电镀技术制备镍/硅纳米线(Ni/Si Nanowires)和钯-镍/硅纳米线(Pd-Ni/Si Nanowires)阵列电极,Pd-Ni/Si Nanowires阵列电极对甲醛有很强电化学催化氧化作用,以其为电化学甲醛传感器工作阳极,以Ni/Si Nanowires阵列为对电极,Ag/AgCl为参考电极,循环伏安技术测试结果显示该传感器对甲醛浓度灵敏度高达0.265 mA/(mmol/L),三倍信噪比检测限为2μmol/L。其次,利用STC12C5410AD单片机产生三角波扫描电压模拟循环伏安原理,可利用回路中因催化氧化产生的峰电流值来监测室内甲醛浓度,并进一步通过恒压电催化将甲醛处理。该设计方案新颖、成本低廉、便于携带,具有较大实际应用价值。

In this paper,a novel indoor formaldehyde sensor was designed.Firstly,a silicon nanowire with great surface to volume was obtained by an electrochemical etching method and modified with nickel（Ni/Si Nanowires）and palladium（Pd-Ni/Si Nanowires）by electroless plating.The Pd-Ni/Si Nanowires electrode has stronger catalysis for formaldehyde when it was used as a working electrode.Ni/Si Nanowires electrode was adopted as a counter electrode,and Ag/AgCl served as a reference electrode.These sensors present a high sensitivity of 0.265 mA/（mmol/L） and the corresponding detection limit of 2 μmol/L at a signal to noise ratio of 3.Furthermore,STC12C5410AD micro controller（MCU）is employed to generate a triangular-wave voltage which could drive the electrochemistry formaldehyde sensor working.The peak current value of the circuit was recorded by the PKD01 unit.The concentration of formaldehyde is detected and disposed according to the peak current value corresponding to the process of catalytic oxidation of formaldehyde.The device is simple,inexpensive,easily integratable,highly sensitive,and portable.