(NaPO₃)₆-assisted wet formation of dispersive Mg(OH)₂ nanoplates

Abstract

Dispersive Mg(OH) 2 hexagonal nanoplates with a diameter of 100-400 nm and a thickness of 20-40 nm were synthesised by treating the flower-like Mg(OH) 2 micro-agglomerates in sodium hexametaphosphate ((NaPO 3 ) 6 ) aqueous solution at 80°C for 12 hours. Compared with the blank experiment, the presence of 0.05 mol L −1 sodium hexametaphosphate accelerated the dissolution and recrystallisation of Mg(OH) 2 owing to the complex interaction between sodium hexametaphosphate and Mg 2+ , leading to the increase of [Mg 2+ ] from 1.05 × 10 −6 to 2.29 × 10 −3 mol L −1 and the formation of Mg(OH) 2 with high crystallinity. Meanwhile, the adsorption of sodium hexametaphosphate on Mg(OH) 2 surface led to the decrease of the zeta potential of Mg(OH) 2 from 3.42 to −25.1 mV, which inhibited the aggregation and promoted the formation of dispersive Mg(OH) 2 nanoplates.

New insights into the beneficial roles of dispersants in reducing negative influence of Mg2+ on molybdenite flotation

“…The change of zeta potential of Mg(OH) 2 from positive (without SH or SS) to negative (with SH or SS) indicates the adsorption of negatively charged SH or SS on Mg(OH) 2 surface. 37,38 3.4 FTIR analysis FTIR spectral analyses (Fig. 5) were carried out to further understand the interaction between dispersants and colloidal Mg(OH) 2 or MoS 2 particles.…”

Transparent Aqueous Mg(OH)2 Nanodispersion for Transparent and Flexible Polymer Film with Enhanced Flame-Retardant Property

“…Meanwhile, the zeta potentials were also detected. The zeta potential of the modified MH in the nanodispersion decreases from 5.42 to −30.3 mV compared to the unmodified MH, which is attributed to the adsorption of the SHMP . The increased negative charges on the MH surface can inhibit the aggregates or agglomerations by the electrostatic repulsion.…”

“…The zeta potential of the modified MH in the nanodispersion decreases from 5.42 to −30.3 mV compared to the unmodified MH, which is attributed to the adsorption of the SHMP. 34 The increased negative charges on the MH surface can inhibit the aggregates or agglomerations by the electrostatic repulsion. Figure 2d shows the photographs of the MH aqueous nanodispersion and unmodified MH suspension in water with the MH solid content of 1 wt %.…”