Novel bimetallic MOF derived N-doped carbon supported Ru nanoparticles for efficient reduction of nitro aromatic compounds and rhodamine B

Abstract

Pollution of freshwater caused by organic compounds, especially nitro aromatic compounds and rhodamine B, has aroused deep concern about the sustainable development of the earth in the past decades. Employing 2D Zn-MOF-Ru(cptpy)₂ as the original material and dicyandiamide as the nitrogen dopant, a variety of novel N-doped carbon supported Ru nanoparticle materials (Ru-NC) have been successfully synthesized through one-step pyrolysis in a nitrogen atmosphere. Impressively, the introduced dicyandiamide can effectively enhance the catalytic activity of Ru-NC towards 4-NP reduction. The as-obtained Ru-NC-15 catalyst demonstrated an excellent catalytic performance towards nitro aromatic compound and rhodamine B reduction with conversions of more than 99%. Further investigations highlighted that the Ru-NC-15 catalyst possesses favorable catalytic stability and broad substrate applicability. The catalytic activity of the Ru-NC-15 catalyst did not decrease significantly after at least 5 times of continuous use, and it had a high conversion for various nitro aromatic compounds. The mass-normalized rate constants of the Ru-NC-15 catalyst were 2675 min⁻¹ g⁻¹ and 1830 min⁻¹ g⁻¹ towards 4-nitrophenol reduction and rhodamine B reduction, respectively, surpassing many catalysts previously reported in the literature. This work inspired the development of a MOF-derived heterogeneous catalyst for the catalytic reduction of nitro aromatic compounds and rhodamine B contaminants.