New perspective of a nano-metal preparation pathway based on the hexahydro-closo-hexaborate anion

Abstract

Today, metal-based nanomaterials play an increasingly important role in the energy, environment, medical and health fields. In order to meet the needs of various fields, it is necessary to continuously develop advanced technologies for preparing metal-based materials. Inspired by previous research, the results of a proof-of-concept experiment show that the hexahydro-closo-hexaborate anion (closo-[B₆H₇]⁻) in the borane cluster family has properties similar to NaBH₄. Closo-[B₆H₇]⁻ can not only convert common precious metal ions such as Au³⁺, Pd²⁺, Pt⁴⁺ and Ag⁺ to the corresponding zero-valence state, but also convert some non-precious metals such as Cu²⁺ and Ni²⁺ to the zero-valent or oxidation state. Closo-[B₆H₇]⁻ moderate reduction to cause rapid aggregation of metal-based materials is not easy compared with NaBH₄. Compared with closo-[B₁2H₁₂]²⁻, closo-[B₆H₇]⁻ achieves the conversion of Pt⁴⁺ to Pt⁰ under ambient conditions, and its reduction performance extends to non-precious metals. The excellent stability and easy modification characteristics determine the universality of the closo-[B₆H₇]⁻ reduction strategy for metal ions.