Photothermal-regulated selective desorption of enantiomers from Ag/Ni3S2 nanosheet-covered Ni foam

Separation of racemates is critically important in the chemical, agrochemical and pharmaceutical industries, since enantiomers may differ in biological interactions, pharmacology, and toxicity. However, the methods for highly enantioselective separation are still insufficient. In this study, we prepared Ni3S2 nanosheet arrays with excellent photothermal properties using Ni foam as the precursor. The PT enantioselective desorption approach is based on a Ni3S2 NSA decorated with Ag nanoparticles modified with D-penicillamine as the enantioselective substrate. Finite-difference time-domain simulation was used to probe the optimal number, shape, and distribution of Ag NP to optimize the localized surface plasmon resonance and photothermal effect. The enantiomers of 3,4-dihydroxyphenylalanine were used as models to demonstrate enantioselective separation based on the different number of stable hydrogen bonds between the homochiral substrate and each enantiomer. This enantioselective desorption approach has the advantages of efficiency, low cost, and recyclability, and provides a new solution for separating racemic molecules.