Contact angle analyzer

The surface energy analysis of CA-based composite films was determined by the measurement of water contact angles. Five parallel measurements were carried out for each film by using a contact angle analyzer (KRUSS, Germany).

The transmittance spectra of HSILs coated on ITO were recorded using an ultraviolet-visible (UV-vis) spectrophotometer (Cary 5000, Agilent Technologies, Inc., Santa Clara, CA, USA). The Raman scattering spectra of HSILs was carried our using a Raman spectrometer (Model inVia, Renishaw, London, UK) with a 532-nm excitation laser line. Fourier-transform infrared (FTIR) spectra were obtained from FTIR spectroscopy (Frontier, PerkinElmer, Inc., Shanghai, China). The morphological modification of HSILs were taken using atomic force microscope (AFM, Model 5500, Agilent Technologies, Inc., Santa Clara, CA, USA). The X-ray photoelectron spectroscopy (XPS) data were evaluated by a PHI Quantera SXM scanning photoelectron spectrometer microprobe (ULVAC, Kanagawa, Japan). A contact angle analyzer (Kruss, Hamburg, Germany) was utilized to take the surface properties (water contact angle) of samples. The WFs of PEDOT:PSS and PEDOT:PSS-ET (v/v, 1:0.5) films deposited on ITO glass were determined using photoelectron yield spectroscopy (PYS) (Riken-Keiki CO., LTD, Tokyo, Japan). The acidic nature of aqueous solutions were taken by pH meter (Mettler Toledo, Shanghai, China). Field emission scanning electron microscopy (Model Hitachi SU8220, Tokyo, Japan) was used to evaluate the thickness of HSIL and photoactive layer (Figure S1).

The contact angle of the films was measured using a contact angle analyzer (Krüss, Hamburg, Germany) and the sessile drop method [33 ]; continuous shooting using dual focus was performed using a CMOS camera (30 fps/s, Basler, Ahrensburg, Germany), and the light source was controlled by an LED cold light source (6000–6500 K) under room temperature. Distilled water (1 μL) was dropped onto the surface of the films, which was measured in five different areas of each surface, and the average values were taken. Lastly, images of the droplets were taken by a camera.