Sodium‐Naphthalenide‐Driven Synthesis of Base‐Metal Nanoparticles and Follow‐up Reactions

Abstract

Mo(0), W(0), Fe(0), Ru(0), Re(0), and Zn(0) nanoparticles—essentially base metals—are prepared as a general strategy by a sodium naphthalenide ([NaNaph])-driven reduction of simple metal chlorides in ethers (1,2-dimethoxyethane (DME), tetrahydrofuran (THF)). All the nanoparticles have diameters ≤10 nm, and they can be obtained either as powder samples or long-term stable suspensions. Direct follow-up reactions (e.g., Mo(0)+S8, FeCl3+AsCl3, ReCl5+MoCl5), moreover, allow the preparation of MoS2, FeAs2, or Re4Mo nanoparticles of similar size as the pristine metals (≤10 nm).

Liquid‐Phase Synthesis of Base Metal Nanoparticles

“…6). Except for the hard metals Mo 0 and W 0 , all the asprepared metal nanoparticles were crystalline as indicated by HRTEM, SAED, and XRD [9]. Mo 0 , W 0 , Fe 0 , Ru 0 , Re 0 , Zn 0 , and Ti 0 nanoparticles were obtained via reduction of less-expensive, commercially available metal chlorides (i.e., MoCl 5 , WCl 6 , FeCl 3 , RuCl 3 , ReCl 5 , ZnCl 2 , TiCl 4 2THF) by injection of [NaNaph] solutions in DME or THF (Tab.…”

“…In principle, [NaNaph] is well-known as a strong reducing agent in inorganic synthesis, for instance, to establish double or triple bonds of main-group elements or to obtain low-valence Si, Ge, or transition-metal compounds [5,9].…”

“…10a) [9,10]. Hence, the Fe 0 nanoparticles can be easily collected from the asprepared DME suspension by putting a bar magnet next to the suspension (Fig.…”

“…To this concern, three different types of liquid-phase synthesis of base metal nanoparticles were explored: i) Liquid-ammonia-in-oil microemulsions (a/o-microemulsions) using liquid ammonia as the polar micelle phase [7]; ii) The sodium-driven reduction and nucleation in liquid ammonia (lq-NH 3 ) [8]; iii) The sodium-naphthalenide-driven ([NaNaph]) reduction and nucleation in ethers [9,10]. Alternative synthesis strategies -preferentially based on low-cost and easy-to-handle starting materials, reducing agents, and solvents -are highly requested.…”

“…Co-reduction reactions and follow-up reactions resulting in FeAs 2 intermetallic phase[9,10], Re 4 Mo alloy[9,10], MoS 2 nanoparticles[9], ZnO hollow nanospheres with a) TEM, b) HRTEM image…”