Microgalvanic cell-mediated green synthesis of Cu2O nanocubes with (100) facets for boosting dopamine hydrochloride sensing performance.

Abstract

Despite numerous efforts have been made on exploring the preparation, properties and application of Cu₂O nanocrystal, there is still a lack of a facile and green synthesis strategy to obtain well-defined Cu₂O nanocubes (NCs). And exploration of the superior low-index lattice plane of Cu₂O in electrochemical sensing is also inadequate. Herein, we proposed a Ni(OH)₂-mediated in-situ synthetic strategy for the preparation of Cu₂O NCs enclosed by low-index facets with simple procedure, mild temperature and low energy-consumption. The Ni(OH)₂ sites not only facilitated the contact between Cu²⁺ and the substrate Ni foam (NF), but also can combine with the NF to act as a primary battery to regulate the nucleation and growth rate of Cu₂O (100) facets. Benefiting from the high ratio of exposed electroneutral (100) lattice planes of nanocubes, the Cu₂O NCs formed on Ni(OH)₂-abundant Ni Foam (Cu₂O NCs/NF_EO) exhibited a wide linear range (3.25-1178.8 μM), a low detection limit (1.86 μM) and a high sensitivity (900 μA mM^-1 cm^-2) in dopamine hydrochloride (DAH) electrochemical sensing. This work expects to provide more clues about the relationship between different dominant low-index facets of Cu₂O NCs and electrochemical sensing performance towards DAH, and thereby contributes to the development of functional materials based on Cu₂O nanocrystals with desirable facets.