Supporting Information

Locking the Morphology with a Green, Fast and Efficient Physical Cross-linking

Approach for Organic Electronic Applications

Qing-Dan Yang1, Yuanhang Cheng1, Ho-Wa Li1, Jiang Liu2, Sin-Hang Cheung,3 Shu-

Kong So,3 Kai-Wai Wong4, Woon-Ming Lau2, Sai-Wing Tsang1*

1. Department of Physics and Materials Science, City University of Hong Kong, Hong

Kong SAR, P. R. China

2. Chengdu Green Energy and Green Manufacturing Technology R&D Center, Chengdu,

Sichuan 610207, P. R. China

3. Physics Department, Baptist University of Hong Kong, Hong Kong SAR, P. R. China

4. Department of Chemical and Biomolecular Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR, P. R. China.

Keywords: hyperthermal hydrogen induced cross-linking, organic field effect transistor,

poly (3-hexylthiophene), stability

Corresponding Author: Sai-Wing Tsang (saitsang@cityu.edu.hk)

Figure S1. Optical microscopy of P3HT films (a) without HHIC treatment and before washing by CB, (b) with HHIC treatment and before washing by CB, (c) without HHIC treatment and after washing by CB, (d) with HHIC treatment and after washing by CB. The glass substrate has a size of 2.5 cm x 2.5 cm.

Figure S2. 2m x 2m AFM images of P3HT films (a) without HHIC treatment, (b) with HHIC treatment, (c) without HHIC treatment after heating at 150 oC for 1 hr, and (d) with HHIC treatment after heating at 150 oC for 1 hr.

Figure S3. 2m x 2m AFM images of P3HT:PCBM(1:1) films (a) without HHIC treatment, (b) with HHIC treatment, (c) without HHIC treatment after heating at 150 oC for 1 hr, and (d) with HHIC treatment after heating at 150 oC for 1 hr.