Effective H2O2 Production from the Radiolysis of Oxygenated Water Assisted by WO3 Nanoparticles-Encapsulated Nickel-Based Metal Hydroxide-Organic Framework

Radiolysis of oxygenated water can produce H2O2 via primary (OH)-O-center dot radical recombination and hydrated electron (e(aq)(-)) transfer to O-2, which is a direct, decentralized, and sustainable process for overall H2O2 synthesis. However, the practicality suffers from poor yield due to low ionizing efficiency and completion of redox reactions. Here, a WO3 nanoparticles-encapsulated nickel-based metal hydroxide-organic framework (Ni-MHOF) is synthesized via a one-step hydrothermal method as a catalyst to address the challenges. Remarkably, it achieves a H2O2 formation yield of similar to 0.67 mu mol J(-1) and a ray-to-chemical conversion efficiency of 8.1% over multiple X-ray irradiation cycles, in the absence of any scarifying agents or electrolytes. Operando experiments using pulse radiolysis and customized in situ X-ray-coupled spectroscopy highlighted the unique capability of Ni-MHOF acting as a radiation-resistant nanoreactor to accelerate e(aq)(-)-driven O-2 reduction and bind the key *OOH intermediates on Ni metal sites. Moreover, the porous structure and periodic arrays facilitate WO3 nanoparticles dispersion and their radiosensitizing merit to produce more (OH)-O-center dot radicals while avoiding undesirable H2O2 dissociation on the surface. The application prospect is further enhanced by using a desktop electron beam to produce H2O2 at a rate of 16.2 mmol/g(cat)/h, and an effective degradation of organic waste enabled by as-synthesized H2O2.