Organic photosensitive devices comprising a squaraine containing organoheterojunction and methods of making same

A method of forming an organic photosensitive optoelectronic device, said method comprising:

• forming at least one Donor-Acceptor heterojunction over a first electrode, the heterojunction comprising at least two donor materials and at least one acceptor material, wherein at least one of the donor materials is formed by depositing a squaraine compound or a combination of squaraine compounds of formula I to a thickness of no more than 100 Å:
• wherein each of Ar1 and Are is independently chosen from an optionally substituted aromatic group;
• and
• forming a second electrode over the at least one Donor-Acceptor heterojunction.

An organic photosensitive optoelectronic device comprising:

• an anode;
• a cathode;
• and
• at least one Donor-Acceptor heterojunction between the cathode and the anode, the heterojunction comprising a donor material and an acceptor material, wherein the donor material is a mixture of at least two different squaraines of formula I and forms a layer no more than 100 Å thick:
• wherein each of Ar1 and Are is independently chosen from an optionally substituted aromatic group.