Insights into the effects of exposed facets of MoS2 on gold recovery from Au(S2O3)23- solution

MoS 2 materials performed well as adsorbent for Au(S 2 O 3 ) 2 3- recovery, but the effect of its crystal facets on recovery behavior and mechanism remained unclear. In this study, flower-shaped MoS 2 with exposed (110) facet and flake-shaped MoS 2 with (002) exposed facet have been synthesized through a simple hydrothermal method, and their recovery performance and mechanism for gold from Au(S 2 O 3 ) 2 3- solution were explored. The results indicated that MoS 2 materials could recover Au(S 2 O 3 ) 2 3- via adsorption and photocatalytic reduction. Importantly, MoS 2 materials with different exposed facets displayed crystal anisotropy, which greatly affected the recovery behavior of Au(S 2 O 3 ) 2 3- . Flake-shaped MoS 2 showed better dispersibility because of stronger surface electronegativity, and flower-shaped MoS 2 displayed better photocatalysis property thanks to more activated edge sites. The better dispersibility made flake-shaped MoS 2 have higher contact probability to Au(S 2 O 3 ) 2 3- molecules, resulting in faster recovery rate as well as higher recovery for Au(S 2 O 3 ) 2 3- with low concentration. Meanwhile, flower-shaped MoS 2 with better photocatalysis property could release more photogenerated electrons, so that achieving more excellent recovery for Au(S 2 O 3 ) 2 3- with high concentration. The finding in this study enhanced the understanding about the effect of MoS 2 facets on Au(S 2 O 3 ) 2 3- recovery, which had great significance for the design of MoS 2 structure and green production of gold in the future.