Supplementing the power generation of visibly transparent solar energy harvesting devices comprising organic semiconductors
Illustrative embodiments of the invention generally relate to photovoltaics and solar energy harvesting devices and, particularly, to those that are transparent or semi-transparent, allowing sufficient visible light through them to allow visualization of objects through them, and more particularly, to those that supplement their primary near ultraviolet light absorption with secondary and/or tertiary absorptions of narrow bands of visible light while maintaining their transparency. Various embodiments of the invention relate to single solar materials with both primary ultraviolet absorption and secondary, narrow-band visible absorption, while some embodiments of the invention utilize mixtures of one or more materials to realize a primary ultraviolet absorption of light with secondary, or even tertiary, narrow bands of visible light absorption. Means of manufacturing such photovoltaics and solar energy harvesting devices will also be disclosed as well as the applications and uses thereof.
1 . A visibly transparent photovoltaic device, comprising:
at least one photosensitive layer having a first absorption peak between and including 350 nm and 420 nm and a second absorption peak between and including 420 nm and 780 nm;
an anode, the anode configured to be in electrical communication with a first surface of the at least one photosensitive layer; and
a cathode, the cathode configured to be in electrical communication with a second surface of the at least one photosensitive layer, wherein:
the at least one photosensitive layer comprises:
a first photosensitive layer comprising an organic electron donor; and
a second photosensitive layer comprising an organic electron acceptor, wherein the first photosensitive layer and the second photosensitive layer form in a bilayer, planar heterojunction;
the first photosensitive layer has the first absorption peak between 350 nm and 420 nm; and
the second photosensitive layer has the second absorption peak between 420 nm and 780 nm; or
the first photosensitive layer has the second absorption peak between 420 nm and 780 nm; and
the second photosensitive layer has the first absorption peak between 350 nm and 420 nm;
the second absorption peak between 420 nm and 780 nm is due to the at least one photosensitive layer comprising one or more of: coumarins; naphthalimides; coronenes; anthracenes; rubrenes; thiophenes; fluorenes; diazafluorenes; fluorenones; dicyanomethylenes; rhodamines, perylenebisimides; or bipyridines;
the visibly transparent photovoltaic device has an average visible transmission (AVT) of between 35% and 95% of incident light having wavelengths of between 400 nm and 780 nm;
values of CIE L*a*b* color coordinates a* and b* of the transmitted visible light are each between negative 30 and positive 30; and
the visibly transparent photovoltaic device generates electrical power.
2 . The photovoltaic device of claim 1 , wherein the second absorption peak has a full-width half-maximum of between 10 nm and 75 nm.
3 . The photovoltaic device of claim 1 , wherein the anode and the cathode independently comprise one or more of LiF/Al, Au, Ag, a transparent conducting oxide, a transparent conducting graphene film, a transparent conducting nanotube film, a transparent metal, a metal, or metal nanowires.
4 . The transparent photovoltaic device of claim 3 , wherein:
the transparent conducting oxide comprises indium tin oxide (ITO), aluminum doped zinc oxide (AZO), zinc oxide, or gallium Zinc oxide (GZO);
the transparent metal comprises Al, Au, Ag, Mo, or Ni;
the metal comprises Al, Au, Ag, Ni, Cu, or Mo; and
the metal nanowires comprise Al, Au, or Ag.
5 . The photovoltaic device of claim 1 , wherein:
the at least one photosensitive layer comprises an organic electron donor and an organic electron acceptor; and
the photovoltaic device comprises a single junction architecture generating an open circuit voltage (Voc) of at least 1.4 V.
6 . The photovoltaic device of claim 1 , wherein the organic electron donor and/or the organic electron acceptor comprise dibenzocoronene derivatives.
7 . The transparent photovoltaic device of claim 1 , wherein:
the organic electron donor comprises a first contorted hexabenzocoronene (cHBC) or cHBC derivative; and
the electron acceptor comprises a second cHBC or cHBC derivative.
8 . The photovoltaic device of claim 5 , wherein the organic electron donor and the organic electron acceptor comprise at least one of a tetrabenzothiophenyldibenzocoronene derivative or a tetrabenzofuranyldibenzocoronene derivative.
9 . The photovoltaic device of claim 1 , further comprising:
one or more electrical components selected from the group consisting of light sensors, color sensors, humidity sensors, temperature sensors, occupancy sensors, motion sensors, cellular signal amplifiers, universal serial bus interfaces, energy storage devices, and wireless communication elements.
10 . The photovoltaic device of claim 9 , wherein the one or more electrical components are electrically powered by the photovoltaic device.
11 . The photovoltaic device of claim 1 , wherein the presence of the second peak absorption in the visible portion of the solar spectrum provides supplemental electrical power to the photovoltaic device to supplement the electrical power produced by the first peak absorption in the UV portion of the solar spectrum while maintaining the AVT above 35% and maintaining the values of the CIE L*a*b* color coordinates from a* and b* of the transmitted visible light being each between negative 30 and positive 30.
12 . The photovoltaic device of claim 1 , further comprising:
a transparent luminescent solar concentrator (LSC) coupled to the visibly transparent photovoltaic device, wherein the transparent LSC is coupled to the anode or the cathode.
13 . A method of making visibly transparent photovoltaic device, comprising:
providing at least one photosensitive layer having a first absorption peak between and including 350 nm and 420 nm and a second absorption peak between and including 420 nm and 780 nm;
providing an anode configured to be in electrical communication with a first surface of the at least one photosensitive layer; and
providing a cathode configured to be in electrical communication with a second surface of the at least one photosensitive layer, wherein:
the at least one photosensitive layer comprises:
a first photosensitive layer comprising an organic electron donor; and
a second photosensitive layer comprising an organic electron acceptor, wherein the first photosensitive layer and the second photosensitive layer form in a bilayer, planar heterojunction;
the first photosensitive layer has the first absorption peak between 350 nm and 420 nm; and
the second photosensitive layer has the second absorption peak between 420 nm and 780 nm; or
the first photosensitive layer has the second absorption peak between 420 nm and 780 nm; and
the second photosensitive layer has the first absorption peak between 350 nm and 420 nm; the second absorption peak between 420 nm and 780 nm is due to dopants dispersed in the at least one photosensitive layer, the dopants comprise one or more of: coumarins; naphthalimides; coronenes; anthracenes; rubrenes; thiophenes; fluorenes; diazafluorenes; fluorenones; dicyanomethylenes; rhodamines, perylenebisimides; or bipyridines;
the visibly transparent photovoltaic device has an average visible transmission (AVT) of between 35% and 95% of incident light having wavelengths of between 400 nm and 780 nm;
values of CIE L*a*b* color coordinates a* and b* of the transmitted visible light are each between negative 30 and positive 30; and
the visibly transparent photovoltaic device generates electrical power.
14 . The method of claim 13 , wherein the second absorption peak has a full-width half-maximum of between 10 nm and 75 nm.
15 . The method of claim 13 , wherein:
providing the anode comprises electrically coupling one or more of LiF/Al, Au, Ag, a transparent conducting oxide, a transparent conducting graphene film, a transparent conducting nanotube film, a transparent metal, a metal, or metal nanowires to the first surface of the at least one photosensitive layer; and
providing the cathode comprises electrically coupling one or more of LiF/Al, Au, Ag, a transparent conducting oxide, a transparent conducting graphene film, a transparent conducting nanotube film, a transparent metal, a metal, or metal nanowires to the second surface of the at least one photosensitive layer.
16 . The method of claim 13 , wherein:
the at least one photosensitive layer comprises an organic electron donor and an organic electron acceptor; and
the photovoltaic device comprises a single junction architecture generating an open circuit voltage (Voc) of at least 1.4 V.
17 . The method of claim 13 , wherein the at least one photosensitive layer comprises:
a first photosensitive layer comprising an organic electron donor; and
a second photosensitive layer comprising an organic electron acceptor, wherein the first photosensitive layer and the second photosensitive layer form in a bilayer, planar heterojunction.