Nanographene-DASM Solar Leaf for Extended Absorption

The patent creates composite molecular structures by combining nanographene cores with donor-acceptor small molecules. The nanographene structure serves as a core platform that is chemically functionalized with DASMs, creating a composite material that extends absorption into the red and infrared regions while maintaining structural organization. This composite approach resolves the contradiction by achieving broad spectrum absorption through material composition rather than complex device architecture.

The patent modifies the optical parameters of the solar absorber by changing the molecular structure from conventional chromophores to nanographene-based DASMs. Specifically, the introduction of nanographene with its extended conjugated system and the attachment of electron donor-acceptor molecules with varying HOMO-LUMO gaps allow tuning of absorption wavelengths. This parameter change enables absorption across blue, red, and infrared regions, resolving the spectrum limitation without requiring complex multi-layer device structures.

The synthesis is divided into distinct segments: first synthesizing the nanographene core with reactive functional groups, then separately preparing donor-acceptor small molecules with complementary reactive groups, and finally coupling them through controlled chemical reactions (Stille coupling, Suzuki cross-coupling, or C-H activation). This segmentation allows each component to be optimized independently and simplifies the overall manufacturing process by breaking down the complex synthesis into manageable steps with well-established reaction protocols.

The patent employs standardized chemical coupling reactions (Stille coupling with organotin intermediates, Suzuki cross-coupling with boronic acid intermediates, or C-H activation with directed metalation intermediates) as intermediary processes to join the nanographene core with DASMs. These intermediary reaction pathways are well-characterized and can be performed under mild conditions, making the overall synthesis more manageable and scalable despite the multi-step nature of the process.