Weak-acceptor-polyacrylonitrile/donor-polyaniline core–shell nanofibers: A novel 1D polymeric heterojunction with high photoconductive properties

A novel one-dimensional (1D) polymeric heterojunction based on weak-acceptor-polyacrylonitrile/donor-polyaniline core–shell nanofibers is designed for photoconductive devices through electrospinning followed by solution polymerization. Such 1D heterojunction can not only provide the large phase-separated nano-interface for effective charges separation between the cores and shells, but also facilitate the mass charge collection and transport along the nanofiber structure, resulting in greatly enhanced optoelectronic performance. The short 0.1 s response time upon irradiation is among the fastest values, as is the short 0.1 s time for return to the non-irradiated state. Extremely high on–off resistivity ratios (exceeding 4 × 104) can be obtained under the drive voltage of only 0.01 V, indicating the energy required for electrical input is very small. Higher drive voltages (a modest 10 V) can provide a very high responsivity of 20 A W−1 driven by 365 nm UV irradiation. Moreover, the as-prepared flexible photoconductive device maintains performance even after bending fatigue tests for bending angles as large as 180°.

A novel polymeric heterojunction based on weak-acceptor-polyacrylonitrile/donor-polyaniline core-shell nanofibers is designed for photoconductive application through electrospinning followed by solution polymerization. The heterojunction provides phase-separated nano-interface for charges separation between the cores and shells, and quasi-one-dimensional charge collection and transport along the nanofiber structure, resulting in greatly enhanced optoelectronic performance.Figure optionsDownload as PowerPoint slideHighlights
► The first example of all-polymeric 1D core–shell acceptor–donor heterojunction for photoelectronics.
► Phase-separated nano-interface for charges separation between the cores and shells.
► Quasi-one-dimensional charge collection and transport along the nanofibers.
► The as-prepared devices can bear fatigue tests without degradation of device performances.
► Excellent photoconductive performance suggests applications viability.