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Abstract
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Core–shell super-structures were developed via π-stacking of poly[benzodithiophene-bis(decyltetradecyl-thien) naphthothiadiazole] (PBDT-DTNT) and poly[bis(triiso-propylsilylethynyl) benzodithiophene-bis(decyltetradecyl-thien) naphthobisthiadiazole] (PBDT-TIPS-DTNT-DT) as conductive shells onto carbon nanotubes (CNTs). Structure of conjugated polymers
substantially determines their deposition model onto CNTs. Regioregular poly(3-hexyl thiophene) (P3HT) chains with
hexyl side chains developed delicate nanofbrils with a base attached to CNT surface. However, PBDT-DTNT and PBDTTIPS-DTNT-DT complicated conductive polymers with fused and infused thiophenic and benzenic rings preferred to be
π-stacked with a face-on manner onto CNT surface and fabricate shells. Grafting of CNT surface with a polythiophene
such as poly(3-dodecyl thiophene) (PDDT) introduced some defects onto the shell structure; because PBDT-DTNT and
PBDT-TIPS-DTNT-DT polymers were not able to be π-deposited onto CNT surface grafted with PDDT. The PDDT grafts
were considered as hindrances against the stacking of complicated polymers. The thickness of PBDT-DTNT and PBDTTIPS-DTNT-DT shells ranged in 10–12 and 5–8 nm, respectively. Higher hindrance of TIPS side structures in PBDT-TIPSDTNT-DT chains reflected thinner shells. By developing core–shells based on PBDT-TIPS-DTNT-DT and PBDT-DTNT,
the conductivity reached 10.11 and 12.15 S/cm, respectively. Donor–acceptor core–shell nano-hybrids were then applied
in active layer of photovoltaics. Efciencies for CNT (core)-PBDT-DTNT (shell) and CNT (core)-PBDT-TIPS-DTNT-DT
(shell) were 4.07 and 2.34%, respectively.
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