Dipole Assisted Photogated Switch in Spiropyran Grafted Polyaniline Nanowires

Abstract

In this work we show dipole-assisted photogated switching by covalent grafting of photoactive molecules to conducting polymers. Photochromic spiropyran molecules were covalently attached to polyaniline (PANI) nanowires via N-alkylation reaction to the quinoic part of PANI. Upon irradiation with ultraviolet light spiropyran transformed to a large dipole containing molecule, merocyanine form. We show that this transformation leads to a substantial (ca. 2 orders of magnitude) increase in conductance of the photochromic PANI nanowires, which were evident by an increase in field-effect mobility and calculated band gap narrowing of the system. Finally, this transformation was found to be fully reversible with no significant photofatigue.

Recent progress in photoactive organic field-effect transistors

“…Crivillers et al reported a similar attempt [107]; an azobenzene-SAM at the electrode– N , N ′-1H,1H-perfluorobutyl dicyanoperylenecarboxydiimide (PDIF-CN 2 ) interface induced a variation in the carrier injection barrier to result in I on / I off = 2.0. Additionally, azobenzene or spiropyran were attached to the surface of low-dimensional materials: graphene, carbon nanotubes, and polymer nanowires [108–110]. In these cases, photochromic molecules are near the carrier flow, and therefore photochromism can influence the drain current.…”

Hydroxyethylcellulose‐graft‐poly(2‐(dimethylamino)ethyl methacrylate) as physically adsorbed coating for protein separation by CE

“…Materials with photochromic SPs have the advantage of reversibly photo‐induce changes in their properties such as conductivity,24, 28, 45 wetting behaviour,9, 11, 22 optical properties,9, 23, 27, 31, 32, 35, 44, 46 metal ion complexation,7–10 cell adhesion,25 surface morphology,9 association/solubility,29, 30 mechanical effects,21, 36 colloidal system stability17, 38 and membrane permeability 15, 16. Therefore, the possibility to photo‐induce such a variation in their physical and chemical properties, has made SP‐based materials widely utilised in biological applications,25 non‐linear optics,47 reversible optical memory,24, 48 optoelectronics49 and chemical sensing 7, 10, 13, 46, 50.…”

Development of molecular photoswitch with very fast photoresponse based on asymmetrical bis-azospiropyran

“…A large variety of applications for photoresponsive molecules has been investigated in highlevel technologies such as controlling the conformation and activity of biomolecules [1][2][3], sensors [4][5][6][7][8][9][10], data recording, optical storage, optical switching [11][12][13][14], displays, non-linear optics [15][16][17][18], and other photochemical and photophysical reactions [19,20].…”