Photocurrent Enhancement in DNA‐Scaffolded Chromophore–Aggregate‐Functionalized Systems Containing Multiple Types of Chromophores

Abstract The construction of one‐dimensional chromophore aggregates of naphthalenediimide (NDI) and bis(2‐thienyl)diketopyrrolopyrrole (TDPP) using 40‐mer oligodeoxythymidines (dT40) as a scaffold was previously reported. Furthermore, the chromophore‐aggregate (NDI‐dT40/TDPP‐dT40) co‐immobilized heterojunction gold electrode exhibited a more efficient photocurrent than the TDPP–dT40‐immobilized electrode with selective photoexcitation of TDPP‐dT40. In this work, a system comprising three components (in which the chromophore aggregates of diphenyl‐diketopyrrolopyrrole (PDPP‐dT40) are employed as a third component) was examined in order to enhance photocurrent efficiency. Selective photoexcitation of TDPP‐dT40 on the NDI‐dT40/TDPP‐dT40/PDPP‐dT40 electrode shows photocurrent responses with greater quantum yield than those of the TDPP‐dT40, NDI‐dT40/TDPP‐dT40 and TDPP‐dT40/PDPP‐dT40 electrodes. The results suggest the addition of PDPP‐dT40 can control charge separation and charge recombination between the electron and the hole (generated by an electron transfer from the photoexcited TDPP‐dT40 to NDI‐dT40).