One-dimensional nanocrystals of cobalt perylene diimide polymer with in-situ generated FeOOH for efficient photocatalytic water oxidation

Abstract We firstly report the large-scale synthesis of one-dimensional (1D) nanocrystals (NCs) of cobalt perylene diimide polymer (PDI-Co), and their application in the photocatalytic water splitting. With the width of ∼80 nm and intrinsic wide light absorption, these NCs exhibit the high activity of photocatalytic oxygen evolution (POE) with Fe(NO3)3 as electron acceptor under visible light (λ > 420 nm). The optimal POE rate may reach up to 27,000 μmol g−1 h−1, which is the highest value so far, even at acidic condition (pH = 2.6). The systematical experiments reveal the synergistic effect of 1D Co-PDI and in-situformation of iron oxy-hydroxide (α-FeOOH) as cocatalyst on POE, and confirm that the fast electron-hole separation (τCS = 0.07 ps) and long recombination time (τCR = 106.1 ps) between adjacent ± ( 01 1 ¯ ) and ±(002) side facets of Co-PDI NCs are critical. The process may be used to construct a Z-scheme system for overall water splitting.