Electro-spray system employed for the deposition of the P3HT films.
(Color online) AFM images of electro-spray (2 kV) deposited P3HT films, from 3 ml solution at different flow rates are reported. For a concentration of 0.1 mg/ml from (a) to (b) the solution flow speed is 1.3 and 4.0 μl/s, respectively. For 0.5 mg/ml solution pictures (c) and (d) are from samples grown with flow rates of 2.0 and 4.0 μl/s, respectively.
(Color online) AFM pictures showing the morphology dependence at different conditions of films grown with a rate of 2.0μl/s at solution concentration of 0.1 (left images) and 0.5 mg/ml (right images) and sample thickness of about 70 (lower images) and 200 nm (upper images).
(Color online) Grazing incidence XRD from P3HT films: from (a) to (c) the diffraction patterns of 0.1 mg/ml solution at the speed of 1.3, 2.0, and 4.0 μl/s, respectively. Curves (d)–(e) represent the patterns of 0.5 mg/ml solution samples grown at 2.0 and 4.0 μl/s flow speed, respectively. In the inset is reported the sketch of the grazing geometry.
Absorption spectra of samples grown at different concentrations of the solution: Panel (a): less concentrated solution (0.1 mg/ml) and speed of 1.3, 2.0, and 4.0 μl/s. Typical spectrum of a spin coated sample is also reported. Panel (b): from the 0.5 mg/ml solution samples grown at 1.3, 2.0, and 4.0 μl/s.
(a) Normal photoemission (HeII) data of the sample grown at low concentration/low speed (type I samples depicted by circles) and high concentration/high speed conditions (type II, squares) at 2 kV voltage. The angle between the light and the detection direction (normal emission) is 45°. (b) Normalized intensity behavior of the localized π states at 3.8 eV BE, as a function of the grazing angle β of photon incidence for the type I (open symbols) and type II samples (full symbols). In the inset is shown the pictorial sketch of the photoemission experiment during β scans.
I-V curves of 100 nm P3HT film sandwiched between ITO/PEDOT-PSS and Al electrodes by lower (a) and higher concentration solution (b), respectively, in dark and ambient illumination conditions.
I-V curves of planar structure of 100 nm P3HT film grown between Al electrodes with 150 μm gap separation by lower and higher concentration solution, respectively, in dark and ambient illumination conditions.
Spectral photoresponse after normalization to incident power for the higher and lower concentration solution samples grown on corning glass. Al metallic contacts have 150 μm separation gap.
Article metrics loading...
Full text loading...