4.3 Materials Chemistry
133
photocurrent density of 3.4 mA/cm
2 , an open circuit voltage of 0.58 V and a power
conversion efficiency of 0.7% [127].
As briefly mentioned above, the photochemical generation of NIs in [60]fullerene
cycloaddition has only recently been reported, when it was utilised in a proofof-concept study by Barner-Kowollik in the synthesis of C 60 -containing polymers
in 2015 [102]. Polyethyleneglycol and poly(tert-butyl)acrylate functionalised with
a diaryl tetrazole were ligated with [60]fullerene in the presence of UV light
(Scheme 4.39), with the protocol also exemplified through the immobilisation of
C 60 on a surface doped with the NI precursor.
The same author also employed NI-[60]fullerene conjugation in polymer crosslinking chemistry. A poly(methyl)acrylate derivative functionalised with 2,5tetrazole was found to form dense networks in the presence of C 60 (Scheme 4.40)
N
N
N
N
O
N N
O
h
o-DCB
rt, 6 h
=
O
n
Scheme 4.39 The application of C 60 as a polymer ligation agent using NI cycloaddition chemistry
EDC, DMAP
THF
rt, 72 h
C
H
H2
C
H
C
O
H2
C C
H
H2
C
H
C
H2
C C
H
H2
C
H
C
H2
C C
H
H2
C
O
O
O
O
O
O
O
OH
OH
OH
OH
O
MeO
O
MeO
O
MeO
C
H
H2
C
H
C
O
H2
C C
H
H2
C
H
C
H2
C C
H
H2
C
H
C
H2
C C
H
H2
C
O
O
O
O
O
O
O
O
O
O
O
O
MeO
O
MeO
O
MeO
O
O
O
O
N
N
PhN
N
N
N
PhN
N
N
N
PhN
N
N
N
PhN
N
NPh
N
PhN
N
N
PhN
NPh
N
N
NPh
N
PhN
N
Ph
N
PhN
N
N
PhN
O
HO
N
N
N
N
h, o-DCB
rt, 14 h
Scheme 4.40 [60]Fullerene as a cross-linking agent in polymer chemistry, mediated by NI
cycloaddition