A Bioinspired Molybdenum Catalyst for Aqueous Perchlorate Reduction

Perchlorate (ClO4-) is a pervasive, harmful, and inert anion on both Earth and Mars. Current technologies for ClO4- reduction entail either harsh conditions or multicomponent enzymatic processes. Herein, we report a heterogeneous (L)Mo-Pd/C catalyst directly prepared from Na2MoO4, a bidentate nitrogen ligand (L), and Pd/C to reduce aqueous ClO4- into Cl- with 1 atm of H-2 at room temperature. A suite of instrument characterizations and probing reactions suggest that the Mo-VI precursor and L at the optimal 1:1 ratio are transformed in situ into oligomeric Mo-IV active sites at the carbon-water interface. For each Mo site, the initial turnover frequency (TOF0) for oxygen atom transfer from ClOx- substrates reached 165 h(-1). The turnover number (TON) reached 3840 after a single batch reduction of 100 mM ClO4-. This study provides a water-compatible, efficient, and robust catalyst to degrade and utilize ClO4- for water purification and space exploration.

Automated summary

This study introduces a hybrid catalyst for reducing aqueous ClO4- into Cl- at room temperature with 1 atm of H-2, showing high turnover number and turnover frequency.