by understanding the photo-absorption of pentacene and constructing the right matrix for e-holes transport.  go and look the polymer electronic field. 

not an expert. but probably the bio-mimetic is not so easy, and most of all:

nature is not so eager on efficiency.. nature has time.. nature needs time..

we humans are too hasty.

Dear Lukas, Firstly, thanks for your suggestion of 'polymer electronic field' & 'bio-mimetic', which I am interested to learn more about.

I would also like to tell that the same hasty Humans hacked the genes of plants some decades ago, for which today we have many hybrid breeds and more resources for applications in medicine, nano technology, bionics, etc..

We humans will never compromise in time, cost & efficiency factors. May be at some point-of-time, humans can be forced to adopt anti-nature strategies, whose long term outcomes are unpredictable. But believe, I augur a day for human is not so far, when he/she completely understand the system 100%. 

?Until this 100% control (at least understanding that there can be no control (hopefully)) is reached by humans, humans should not forget where they come from and be much more respectful to mother nature..

clean our seas from plastic, stop fission reactors (and disseminate/(safely store) all the waste), find an alternative to Carbon burning energy..

somehow we make ourselves hasty by our blind look to technology.. something is wrong about growth? somehow by nature instable..

is there any stability point for an earth with homosapiens ?  I wish, but I doubt..

for sure, going to solar energy is a must..

I am proud the germans go this way (today in a much slower pace). 

30% of green power is the last what every country in the world should reach now! or within 15 years (like germans did).

Good luck