The activation of C–H bonds for carbon–carbon coupling reactions remains a challenge in organic synthesis. Visible light photocatalysis offers a unique opportunity to sustainably perform these reactions in a single-step, without the need for caustic reagents, and under ambient operating conditions. We utilize non-noble metals in the form of hybrid cobalt-based zeolitic imidazole frameworks, for the first time, to explore the structure–property correlations leading to the photocatalytic formation of C–C bonds. Combining in situ spectroscopy and theoretical simulations we can rationalize the photocatalytic efficacy of different frameworks. This led to an improved understanding of the nature of the photocatalytic active sites and associated reaction pathway.