Synthesis of one-dimensional nickel perylene diimide/iron hydroxide nanohybrid as catalyst and precursor for efficient photocatalytic and electrocatalytic water oxidation

Abstract

The sluggish oxygen evolution reaction (OER) attracts increasing attention for the storage and/or conversion of clean energy. However, the whole design of precursor and product is studied a few for efficient photocatalytic and electrocatalytic water oxidation. Here, we report the large-scale synthesis of one-dimensional (1D) nanohybrids (NHs) of 50-nm nickel perylene diimide (Ni-PDI) nanowires loading iron hydroxide (Fe(OH)3) nanoparticles through one-step hydrothermal reaction. The Fe(OH)3@Ni-PDI NHs as OER photocatalyst possess the super activity, even high electrocatalytic performance after pyrolysis. Under visible light (λ > 420 nm), the photocatalytic oxygen evolution rate of 22,000 μmol g−1 h−1 can be achieved via the synergy between 1D Ni-PDI nanowires and in-situ generated iron (oxy)hydroxide as cocatalyst. Through pyrolysis of 1D Fe(OH)3@Ni-PDI NHs, the NiFe nanoparticles covered by NiFe2O4 layer can be synthesized on 30-nm nitrogen-doped carbon nanowires (NiFe/NiFe2O4@NC). After optimizing the mole ratio of nickel to iron atoms (2:1) and pyrolysis temperature (800 °C), as-obtained sample exhibits the OER activity with the overpotential of 256 mV at 10 mA cm−2 and Tafel slope of 40 mV dec−1 in 1.0 M KOH. The work provides a universal strategy to design 1D nanostructure for efficient OER catalysis.