Colloidal Synthesis of Thiospinel High-Entropy Sulfide Star-like Nanocrystals with High Cycling Stability for the Oxygen Evolution Reaction.

High-entropy semiconducting nanocrystals involving the random incorporation of five or more metals within a single, disordered lattice are receiving significant research interest as catalytic materials. Among these, high-entropy sulfide (HES) nanocrystals demonstrate potential as electrocatalysts but have been slower to gain research interest compared to other high-entropy systems due to the complications introduced by multistep, high-temperature synthesis techniques and the issues of material stability during performance. In this work, we report a simple, reproducible, and scalable HES synthesis to produce star-like nanocrystals.

Scalable Route to Colloidal NiCoS Nanoparticles with Low Dispersity Using Amino Acids.

The thiospinel group of nickel cobalt sulfides (NiCoS) are promising materials for energy applications such as supercapacitors, fuel cells, and solar cells. Solution-processible nanoparticles of NiCoS have advantages of low cost and fabrication of high-performance energy devices due to their high surface-to-volume ratio, which increases the electrochemically active surface area and shortens the ionic diffusion path. The current approaches to synthesize NiCoS nanoparticles are often based on hydrothermal or solvothermal methods that are difficult to scale up safely and efficiently and that preclude monitoring the reaction through aliquots, making optimization of size and dispersity challenging, typically resulting in aggregated nanoparticles with polydisperse sizes.