Molecular–Supramolecular Light Harvesting for Photochemical Energy Conversion: Making Every Photon Count

Photochemical conversion and storage of solar energy, in which the energy conversion process is initiated by the capture of photons and the subsequent energy delivery, is a sustainable way to partially cover future human energy needs. Diverse artificial light-harvesting techniques have been realized and applied in solar energy conversion as a result of decades of effort. In this Perspective, challenges and developing trends of molecular–​supramolecular light-harvesting systems for photochemical solar energy conversion are discussed. Advances and potential strategies for construction of exceptional light-harvesting systems by merging molecular and supramolecular tailoring, singlet fission, and triplet–triplet annihilation are presented.