Advances in the light conversion properties of Cu(I)-based photosensitizers

Abstract The need to develop low-cost, sustainable, earth abundant fuel sources is becoming paramount as the rate of global energy consumption continues to increase. Toward this goal, solar energy conversion is an obvious choice, yet the current molecular based technologies still rely heavily on expensive, non-earth abundant photosensitizers, which limits the net benefits of these systems. Complexes of copper(I) have been recognized for decades as viable low-cost, earth abundant alternative photosensitizers in solar energy conversion technologies; however, when used in solution based applications, issues such as geometrical distortions associated with photoexcitation and ligand lability has frustrated numerous research efforts. Fortunately, these investigations have not been in vain, and many investigations have successfully circumvented the aforementioned issues. Recent reports on Cu(I) based photosensitizers demonstrate that they are beginning to rival the performance metrics of the more costly, less earth abundant species typically used in solution-based solar energy conversion schemes. Therefore, this minireview focuses on the most recent and influential advances made in the field of Cu(I) based photosensitizers.

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