Self-Assembly Of Poly(3-hexylthiophene)-block-polylactide BlockCopolymer And Subsequent Incorporation Of Electron Acceptor

It is commonly accepted that in order to develop high-performance organic and/or hybrid organic-inorganic solar energy devices, it is necessary to use, among other components, an active donor-acceptor layer with highly ordered nanoscale morphology. In an idealized morphology, the effectiveness of internal processes including exciton generation and separation and charge carrier migration is optimized, leading to an efficient conversion of photons to electricity. With this idea in mind, we have rationally designed and developed an ordered nanoscale morphology consisting of self-assembled poly(3-hexylthiophene) donor domains of molecular dimension.1. A poly(3-hexylthiophene)-block-poly(L-lactide) block copolymer was synthesized and used as a structure directing agent to pattern active material into ordered nanostructures. Its chemical structures and phase-separation behavior for various organic solvents and cooling temperatures was investigated by means of IR, X-rd, AFM and SEM.2. The results showed that the self-assembled domain shapes can be tuned by adjusting the relative volume fraction of each block (f), Flory-Huggins interaction parameter χ, and the degree of polymerization N. In a typical P3HT-PLA, the dimension of the domains range from 10 nm to 100 nm and can be controlled by changing the overall molecular weight of the macromolecule. The self-assembly behaviors generated a typical phase-separation morphology consisting of vertically conducting P3HT nanodomains which varied with the molecular weight of the P3HT.3. Regioregularity Effect on Aggregation was investigated by means of UV, Hall, CV and Photoluminescence (PL). The PL spectra and UV spectra show that Vertically conducting is better than Double-gyroid P3HT and lanmellae P3HT.The devices made of the self-assembly of Vertically conducting P3HT nanodomains/C60 show the larger Jsc, FF, and PCE than the devices from the Double-gyroid phase and lanmellae P3HT/C60 having the same regioregularity, but devices fabricated with Double-gyroid phase/C60 showed about 5～10% better FF than other.