Figure 7
(a) 3D bar plot demonstrating the mean values \({\Delta \lambda }_{100\%}\) of six sensors (S1: no GO, S2: 1 mg/ mL, S3: 2 mg/ mL, S4: 3 mg/ mL, S5: 4 mg/ mL, and S6: 5 mg/ mL) when measuring 6 VOCs and DI water at 5% concentrations with 4 record data. (b) 3D scatter plot of PCA scores to show classification of the VOC measurements based on the six sensors.
