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Abstract
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Two types of core–shell and core–mantle–shell supramolecules were designed based on graftedcarbon nanotubes (CNTs) and poly[benzodithiophene-bis(decyltetradecyl-thien)naphthothiadiazole]
(PBDT-DTNT) chains and employed in the active layers of PBDT-DTNT:phenyl-C61-butyric acid methyl
ester (PC71BM) solar cells to stabilize the morphology and performance. These nano-hybrids were
composed of CNT-g-poly(3-dodecylthiophene) (PDDT)/PBDT-DTNT and CNT-g-polyaniline (PANI)/
PBDT-DTNT precursors, respectively. The overall diameter of the core–shell and core–mantle–shell
nanostructures ranged within 85–95 and 110–120 nm, respectively. In contrast to the pure CNTs
(3.55%), the pre-designed core (CNT)–shell (PBDT-DTNT) and core (CNT)–mantle (PANI)–shell (PBDTDTNT) nanostructures considerably affected the photovoltaic characteristics and efficiencies of 4.83 and
6.71% were acquired, respectively. From the pure CNT-based photovoltaics towards the core–shell and
core–mantle–shell modified systems, the slopes of decreasing curves of short circuit current density
(Jsc), fill factor (FF), open circuit voltage (Voc) and power conversion efficiency (PCE) versus aging time
became slower, proving higher stability in the well-functioning photovoltaic devices. The core–mantle–
shell nanostructures not only largely phase separated and absorbed at more red-shifted wavelengths,
but also further stabilized the device morphology and performance. Within 1 month aging, the characteristics of (9.69 mA cm2, 52%, 0.57 V, 2.3 106 cm2 V1 s1, 4.8 105 cm2 V1 s1, 806 O cm2
and 2.87%) and (12.74 mA cm2, 64%, 0.64 V, 8.4 105 cm2 V1 s1, 9.7 104 cm2 V1 s1, 543 O cm2 and
5.21%) were retained for the core–shell and core–mantle–shell based systems, respectively.
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