English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The internal quantum efficiency (IQE) of an organic photovoltaic device (OPV)is proportional to the number of free charge carriers generated and theirconductivity, per absorbed photon. However, both the IQE and the quantitiesthat determine it, for example, electron-hole binding, charge separation,electron-hole recombination, and conductivity, can only be inferred indirectlyfrom experiments. Using density functional theory, we calculate theexcited-state formation energy, charge transfer, and zero-bias conductance inthe singlet ground state and triplet excited state across polymer/fullerene andpolymer/single walled carbon nanotube (SWNT) OPV donor/acceptor bulkheterojunctions. Specifically, we compare polythiophene (PT) andpoly(3-methylthiophene-2,5-diyl) (P3MT) as donors and C$_{60}$ chains with(6,4), (6,5), and (10,5) SWNTs as acceptors. We find the conductivity increasessubstantially for both the excited triplet relative to the singlet ground stateand for PT compared with P3MT due to the increased charge transfer and theresulting improvement in donor/acceptor level alignment. Similarly, the (6,4)SWNT, with a larger SWNT band gap and greater conductivity than fullerenes,provides the highest conductivities of 5 and 9\% of the theoretical maximum forelectron and hole carriers, respectively. This work has important implicationsfor both the optimization of polymer/SWNT bulk heterojunctions and the designof new OPV bulk heterojunctions in silico.

Theoretical Insight into the Internal Quantum Efficiencies of Polymer/C$_{60}$ and Polymer/SWNT Photovoltaic Devices