Conductivity testing with varied RH% of POM films

Raw data for the paper submitted 'Post transition metal substituted Keggin POMs as thin film chemiresistive sensors for H2O and CO2 detection' Current-voltage (IV) measurements were performed between -2 V and 2 V with a step size of 0.1 V and scan rate of 1 Vs-1. Measurements were taken in the forward and reverse direction. The resistance of the device was calculated through the inverse slope of the resultant linear plot, from which the conductivity was calculated using equation 1.1 The length and width of the channel were measured with an optical microscope. Where σ: conductivity, ρ: resistivity, R: resistance in ohms, L: length in metres, A: the area in m2, V: voltage, and I: current. Samples were measured in a humidity-controlled environment with a purpose-built holder and printed circuit board (PCB), coupled with a QTenki humidity sensor and temperature probe (Dracal Technologies). The appropriate gas (either air, N2, or CO2 only) was passed through the water bubbler before passing through the sample container. The container was purged for 15 minutes with the respective gas prior to each measurement. The flow rate was adjusted to control the humidity. Four repeat measurements were taken for each POM electrode.已投稿论文《后过渡金属取代Keggin型多金属氧酸盐（Keggin POMs）用于H₂O与CO₂检测的薄膜化学电阻型气体传感器》的原始实验数据相关测试细节如下：电流-电压（Current-Voltage, IV）测试在-2 V至2 V的电压区间内进行，步进电压为0.1 V，扫描速率为1 V·s⁻¹，测试分别沿正向与反向扫描方向完成。器件电阻通过所得线性拟合曲线的斜率倒数计算得到，再通过式1.1由电阻推导得到电导率。通道的长度与宽度通过光学显微镜测得。其中，σ代表电导率，ρ代表电阻率，R代表以欧姆（Ω）为单位的电阻，L代表以米（m）为单位的长度，A代表以平方米（m²）为单位的截面积，V代表测试电压，I代表测试电流。样品测试在湿度可控环境中开展，采用定制样品支架与印刷电路板（Printed Circuit Board, PCB），搭配QTenki湿度传感器及Dracal Technologies公司生产的温度探针。待通入样品池的目标气体（仅为空气、氮气（N₂）或二氧化碳（CO₂））需先经过水鼓泡器，再流入样品池。每次测试前，均使用对应气体对样品池吹扫15分钟，通过调节气体流速以控制环境湿度。每个多金属氧酸盐电极均进行四次重复测试。