Research Information System
Carbon, vol.256, 2026 (SCI-Expanded, Scopus)
Triply periodic minimal surface (TPMS) lattices provide a powerful framework for engineering transport and interfacial phenomena through geometry. Here, Cu2+ adsorption is investigated in carbon nanotube (CNT)-modified TPMS monoliths, establishing quantitative links between architecture, hydrodynamics, and adsorption performance under continuous-flow conditions. CNT-integrated TPMS structures with four geometries (IWP (I-WP minimal surface), Gyroid, Neovius, and Primitive) were fabricated and evaluated under identical operating conditions. Continuous recirculation experiments at an inlet velocity of 0.26 m/s, interpreted using a pseudo-first-order kinetic framework, yielded similar apparent rate constants (4.0–5.6 × 10−3 s−1) across geometries, while equilibrium adsorption capacities were strongly geometry dependent. IWP and Gyroid exhibited the highest uptake (∼40–44 mmol/m2), whereas Neovius and Primitive showed substantially lower capacities (∼18–25 mmol/m2). Increasing flow velocity enhanced both adsorption rates and equilibrium uptake, with removal efficiencies approaching 95%. Multiphysics simulations were performed to elucidate the mechanistic origin of these trends. The results demonstrate that TPMS geometry governs adsorption through its control of flow topology and near-wall mass transfer. IWP and Gyroid promote more homogeneous velocity fields, reduced stagnant regions, thinner concentration boundary layers, and higher Sherwood numbers and wall shear stress, enabling more effective utilization of CNT adsorption sites. In contrast, Neovius and Primitive develop persistent low-velocity pockets and bulk–wall concentration gradients that limit adsorption. Simulations further capture early-time concentration transients inaccessible experimentally, providing insight into initial adsorption dynamics. These findings establish geometry as a key design parameter for carbon-based monolithic adsorbents in flow-through systems.