Hydrogen Production and In Situ Storage through Process of Water Splitting Using Mono/Binary Metal–Organic Framework (MOF) Structures as New Chief Photocatalysts

Metal–organic frameworks (MOFs) have been of extensive use in several applications such as gas purification, low-temperature catalytic reactions, and removal of organic compounds from fluids. However, MOFs structures have not been ever introduced as main catalysts for the processes of hydrogen generation via water splitting in which metal oxides are commonly used as photocatalysts. Thus, this research study introduces the first reveal of MOF as a new photocatalyst for such a route of hydrogen production. Specifically, two MOF structures that respectively have mono and binary central metal ions, namely, nickel-benzene di-carboxylic acid (Ni-BDC) and nickel/copper-benzene tri-carboxylic acid (Ni/Cu-BTC), were synthesized. The structural, thermal, and texture characteristics of as-prepared MOFs were determined using the appropriate analytical techniques. Both structures had been then forwarded to the photocatalytic hydrogen production application. The Ni-MOF had exhibited a proper hydrogen productivity of 200 mmol/h with a hydrogen purity of 50%. On the other hand, the Ni/Cu-MOF showed an entire hydrogen storage, which is likely due to the presence of two metal cations within the MOF structure.