Engineering slit-inter-layered architecture in sodium alginate-based cryogels with tanning-reinforced domain-limiting...

GO/SA gel with slit-shaped structure can form through the multi-layer piling of graphene oxide (GO) nanosheets and cross-linking with sodium alginate (SA). A SA-based frozen gel BTGMS is designed by introducing layered montmorillonite (MMT), cowhide collagen (BHC) and tannin (TE) into GO/SA gel to efficiently and selectively adsorb Cu(II) complex. Based on the domain-limiting effect upon slit-shaped structure towards planar Cu(II) complex, the Qₑ^max of BTGMS reaches 150.1 mg/g, and its selective removal rate can still reach more than 84 % in complex surroundings. The utilization of molecular dynamics simulations examines essential contributions of constituents to BTGMS formation, slit-shaped structure, compactness as well as adsorption activity, and verify the functional components and Cu(II) adsorption pathway for BTGMS. The key roles of laminar structure reinforcement and vegetable tanning effect under investigation to strengthening slit-shaped structure, promoting 3D configuration stabilization, increasing cross-linking compactness and enhancing the selective adsorption performance towards Cu(II). Our study can provide effective ideas for the structural design, adsorption activity and mechanism study on highly effective selective Cu(II) adsorbents.