Organic solarcells(OSCs)haverecentlyattractedkeenatten-
tion becauseoftheirstrongcompetitivenessagainstconventional
inorganic solarcellsintermsofviablelow-costfabricationof
ultra-thin flexiblesolarmodules [1–3]. Althoughsmallmolecule-
based OSCsexhibitedimprovedefficiency,mostofresearcheshave
been concentratedonpolymer-basedOSCsowingtothepractical
viability ofusingwet-coatingprocessesatroomtemperature
under atmosphericpressurewithoutusingexpensivevacuum
systems [1–4]. Theadvancementinthepolymer-basedOSCs
(mostly polymer:fullerenesolarcells)hasbeenfueledbyseries
of in-depthresearchesonthebulkheterojunctionnanomorphol-
ogy aswellasinventionofnewmaterials(conjugatedpolymers
and solublefullerenes)