Diatomite supported hierarchical 2D CoNi3O4 nanoribbons as highly efficient peroxymonosulfate catalyst for atrazine degradation

The reactive oxygen radicals generated by peroxymonosulfate (PMS) activation exhibit great potential to deal with refractory contaminants of emerging concern. However, mass production of efficient and cost-effective catalysts for PMS activation is still a long-term goal for its widespread practical application. Herein, a novel CoNi3O4/diatomite hybrid is constructed through vertically oriented growth of 2D CoNi3O4 nanoribbons with atomic layer-thickness on cost-effective diatomite template. Distinct from stacked CoNi3O4, CoNi3O4/diatomite composite possesses abundant exposed edges, sharp corners, and open diffusion channels. Abundant exposed edges and sharp corners create more open space and active sites for PMS activation. Open diffusion channels accelerate the migration of PMS and contaminants. Such characteristics offer CoNi3O4/diatomite hybrid excellent PMS activation efficiency. Furthermore, sulfate radical plays the dominant role in atrazine degradation. Superoxide radical contributes to reversible redox cycle of Co2+/Co3+ and Ni2+/Ni3+. This study provides a novel strategy for cost-effective mass production of various Fenton-like 2D catalysts.