Photovoltaics are an interesting case where atomic precision is not necessary to achieve potentially dramatic global impacts. Even an “ok efficiency” device that is easy to manufacture with reduced environmental hazard could have significant beneficial effects on energy resources and on device fabrication processes (which could, in turn, contribute to developments toward APM).
The struggle to balance ease of manufacture and device efficiency is a major driver behind current research efforts. Two recent publications out of Massachusetts alone make the point: Research from University of Massachusetts Amherst describes the fabrication of (very low efficiency) photovoltaic devices via tunable self-assembly of aqueous nanoparticle dispersions (organic nanospheres). The work is published in NanoLetters and the press release is reprinted at Phys.org here (excerpt below), and research from MIT utilizes quantum dots to reach a notable 9% efficiency (high for QD-based devices). This work is published in ACSNano and the press release also reprinted at Phys.org here.
A team of materials chemists, polymer scientists, device physicists and others at the University of Massachusetts Amherst today report a breakthrough technique for controlling molecular assembly of nanoparticles over multiple length scales that should allow faster, cheaper, more ecologically friendly manufacture of organic photovoltaics and other electronic devices. Details are in the current issue of Nano Letters.
Lead investigator, chemist Dhandapani Venkataraman, points out that the new techniques successfully address two major goals for device manufacture: controlling molecular assembly and avoiding toxic solvents like chlorobenzene. “Now we have a rational way of controlling this assembly in a water-based system,” he says. “It’s a completely new way to look at problems. With this technique we can force it into the exact structure that you want.”
-Posted by Stephanie C