*2.6. Electrochemical Surface Area Experiments*

Electrochemical surface areas of compounds **1** and **2** were estimated by the capacitance of the double layer *C*dl, which were determined by cyclic voltammetry tests [42]. For the cyclic voltammetry tests of **1** and **2**, glassy carbon electrode (3 mm diameter) was dripped with 5 μL isopropanol suspension of **1** or **2**, and served as the working electrode. The potential window was 0.01–0.13 V vs. Ag/Ag+, where no Faradaic processes occur. The scan rates were 10 mV s<sup>−</sup>1, 20 mV s<sup>−</sup>1, 30 mV s<sup>−</sup>1, 40 mV s<sup>−</sup>1, 50 mV s<sup>−</sup>1, 60 mV s<sup>−</sup>1, 70 mV s<sup>−</sup>1, 80 mV s<sup>−</sup>1, 90 mV s<sup>−</sup>1, and 100 mV s<sup>−</sup>1. The *C*dl was calculated by plotting the relationship between Δ*j* and scanning rate at 0.07 V (Δ*j* = *j*<sup>a</sup> − *j*c, *j*a, and *j*<sup>c</sup> represent the current densities of the anode and cathode, respectively), and the slope of the image is twice that of *C*dl.
