Pyrene units are grafted on a D-A polymer by amidation to construct a D + -A structure and improve H 2 O 2 production. Experimental results show that the H 2 O 2 generation rate of this D + -A polymer (PTM-PY) is 2.94 mmol g −1 h −1 , which is higher than the original D-A polymer (PTM) under the same conditions. Mechanistic studies reveal that the increased photocatalytic performance of PTM-PY is attributed to the enhanced light-harvesting capacity and electron push-pull interactions after grafting pyrene as a donor. Therefore, grafting the appropriate small organic molecules on the D-A polymer skeleton can improve their performance further, in addition to the routine methods of optimizing the donor/acceptor ratio and reaction conditions. This is the first report of small organic molecules grafted on a D-A polymer to construct a D + -A polymer for photocatalytic H 2 O 2 generation.
As the cornerstone of the modern information technology, the development of memory devices with high speed, large capacity, long life time, low power consumption and ease of operation characteristics is beneficial for the fast revolution of the digital world. Using soluble 4-bromobenzene functionalized reduced graphene oxide (RGBr) as two dimensional template, in-situ growing of a novel donor-accept type conjugated polymer “poly[(1,4-diethynyl- benzene)- alt -(4,4′-(quinoxaline-2,3-diyl)bis( N , N -diphenylaniline))](PDQ)” from the RGO surface has been successfully realized via the palladium-catalyzed Sonogashira-Hagihara polymerization. The resultant material called as RGO-PDQ is highly soluble in some common organic solvents . The nonvolatile ternary rewritable memory performance has been observed in an electronic device with the RGO-PDQ film sandwiched between the Al and ITO electrodes. The switching threshold voltages on the ON-1 and ON-2 states are −0.74 and −1.44 V, respectively. The achieved current ratio of OFF: ON-1: ON-2 is about 1: 10: 10 4 . The memory effect of the Al/RGO-PDQ/ITO device on the ON-1state can be assigned to the contribution of the PDQ moieties in the structure of RGO-PDQ. By using conductive atomic force microscopy (C-AFM) technique, the conductive nature of the RGO-PDQ film-based device was in-situ observed.
Di Zhao,Qiuhong Cui,Xingyu Zhang,Hongyu Ji,Xin Liu,Liang Qin,Yuanyuan Hu,Yanbing Hou,Yufeng Hu,Zhidong Lou,Feng Teng
Organic salt doping is an effective method to control the electrical properties of organic semiconductor materials, while its underlying mechanism remains to be studied. In this work, we report the improvement of organic field-effect transistor (OFET) performance by doping the D-A polymer semiconductor PTB7-Th with organic salts. The underlying mechanism of PTB7-Th's organic salt doping in OFETs has been explored to fill the existing research gap. The doping of organic salts can improve the hole mobility of the device and change the threshold voltage . In addition, at low doping ratios, the on-off ratio of the device is not sacrificed but remains unchanged. Finally, we have made a series of characterizations of the properties of doped polymers through absorption, EPR , and UPS , which provide specific guidelines for modifying D-A polymer devices.