Synthesis and photophysics of a novel photocatalyst for hydrogen production based on a tetrapyridoacridine bridging ligand

► Synthesis of the novel photocatalyst [(tbbpy)2Ru(tpac)PdCl2]2+RutpacPd. ► Correlation of intramolecular electron transfer with catalytic turnover. ► Reduced sensitivity to water caused by the tpac bridging-ligand. ► Dynamics in tetrapyrido[3,2-a:2′,3′-c:3″,2″-h:2‴,3‴-j]acridine complex.