Toward Inexpensive Photocatalytic Hydrogen Evolution: A Nickel Sulfide Catalyst Supported on a High-Stability Metal-Organic Framework

Few-atom dusters composed of nickel and sulfur have been successfully installed into the Zr(IV)-based metal-organic framework (MOP) NU-1000 via ALD-like chemistry (ALD = atomic layer deposition). X-ray photoelectron spectroscopy and Raman spectroscopy are used to determine that primarily Ni2+ and S2- sites are deposited within the MOF. In a pH 7 buffered aqueous solution, the porous catalyst is able to produce H-2 gas at a rate of 3.1 mmol g(-1) h(-1) upon UV irradiation, whereas no H-2 is generated by irradiating bare NU-1000. Upon visible light irradiation, little H-2 generation was observed; however, with the addition of an organic dye, rose bengal, NiS-AIM can catalyze the production of H-2 at an enhanced rate of 4.8 mmol g(-1) h(-1). These results indicate that ALD in MOFs (AIM) can engender reactivity within high surface area supports for applications in the solar fuels field.