Improved Transistor Performance of Isoindigo-Based Conjugated Polymers by Chemically Blending Strongly Electron-Deficient Units with Low Content To Optimize Crystal Structure

Conjugated polymers have received tremendous attention because of their potential application in flexible electronic devices. In addition to synthesizing new conjugated polymers, different methods have been used to improve charge carrier transport. The simple random polymer strategy was used to enhance the charge carrier mobility of isoindigo (ID)-based conjugated polymers by chemically blending a small amount of strongly electron-deficient bis­(2-oxoindolin-3-ylidene)­benzo­difurandione (BIBDF) units. In comparison with a parent polymer (<b>P0</b>) without BIBDF in its polymer backbone, the hole mobilities of random polymers were remarkably enhanced by the chemical blending of BIBDF with low content (<5 mol %). The polymer with 3.75 mol % BIBDF exhibited the highest mobility, 2.17 cm² V^–1 s^–1 with a high <i>I</i>_on/<i>I</i>_off ratio over 10⁶, which was 3 times higher than that of the organic field effect transistors (OFETs) fabricated from the reference D–A polymer <b>P0</b>. The thin films of very polymer were characterized by grazing incidence X-ray diffraction (GIXD) and atomic force microscopy (AFM). The results reveal that the remarkable enhancement of charge mobility upon chemical blending of BIBDF was due to the improvement in crystal structure by the presence of the BIBDF unit, promoting a more ordered lamellar packing and facilitating a small π–π stacking

Synthesis of Spiroaminals and Spiroketals with Bimetallic Relay Catalysis

A novel tandem metal relay catalytic system was developed by combining gold-catalyzed cycloisomerization with an early transition-metal-catalyzed inverse-electron-demand hetero-Diels–Alder (IED-HDA) reaction. Various biologically important spiroaminals and spiroketals were obtained with very high efficiency under mild conditions

Additional file 1 of Prevalence, associated factors, and gene polymorphisms of obesity in Tibetan adults in Qinghai, China

Supplementary Material