Abstract
Heavy-duty freight transportation contributes significantly to global greenhouse gas emissions, prompting an urgent transition toward zero-emission hydrogen fuel cell electric vehicles. However, conventional 70 MPa compressed hydrogen gas storage suffers from severe volumetric inefficiencies, safety risks, and high compression costs. This study presents a computational and experimental optimization of open-metal site enriched zirconium- and nickel-based Metal-Organic Frameworks (MOFs) tailored specifically for volumetric hydrogen adsorption in heavy-duty fuel cell truck fleets under cryo-adsorptive conditions (77–150 K, 1–10 MPa). By functionalizing UiO-67 frameworks with open Ni(II) coordination centers and tuning pore size distribution through linker modification, we synthesized a candidate adsorbent, designated UiO-67-Ni, which achieved a volumetric hydrogen storage density of 48.2 g H2/L at 100 K and 5 MPa, representing a 38% enhancement over unmodified frameworks. Finite element thermal management simulations of a 350-liter onboard multi-tubular bed revealed a 34% reduction in peak refueling temperatures compared to MOF-5 benchmarks, facilitating 10-minute fast-refueling targets. Fleet-level techno-economic and lifecycle modeling indicates that integrating UiO-67-Ni cryo-adsorptive storage increases operational vehicle range by 28% without sacrificing cargo payload volume, while reducing the total cost of ownership by $0.12 per vehicle-kilometer. These results demonstrate that engineered MOFs offer a commercially viable pathway toward high-density onboard energy storage for heavy-duty sustainable logistics.
