(345b) Superstructured Materials for Energy Conversion and Storage

In solid oxide fuel cells (SOFCs), oxygen ions transfer through the sintered solid oxide electrolyte dense membrane, requiring high operating temperatures (800 ^oC or higher). However, we recently demonstrated a new type of solid fuel cell, carbonate-superstructured solid fuel cell, in which in situ generation of superstructured-carbonate in the porous samarium-doped ceria layer creates an interface as the ultrafast O^2- transfer channel, achieving the unprecedented high cell open circle voltage of 1.041 and a high peak power density of 215 mW cm^–2 with dry methane fuel at 550 ^oC (PNAS 2022, 119, e2208750119).

Large mass-loading for a practical supercapacitor electrode usually leads to inferior charge transfer rate and thus poor utilization efficiency of electroactive materials. To solve the issue, we successfully synthesized the novel superstructured NiMoO₄@CoMoO₄ core-shell nanofiber arrays on Mo-transition-layer-modified nickel foam (NF) current collector as a new material, achieving the synergistic combination of highly conductive CoMoO₄ and electrochemical active NiMoO₄. Such a superstructured material exhibited a large gravimetric capacitance of 1282.2 F/g in 2 M KOH with a mass-loading of 7.8 mg/cm², leading to an ultrahigh areal capacitance of 10.0 F/cm² (PNAS 2023, 120, e2219950120).

The completely destroying the biocomponents of dead leaves is required by current treatment techniques, causing energy and environmental issues. However, we recently developed a new approach, in which dead leaves became an active multifunctional material with a superstructure by exploiting whewellite biomineral for binding lignin and cellulose. This material showed excellent performance in solar water evaporation, photocatalytic hydrogen production, and photocatalytic degradation of antibiotics (Nature Communications 2023, 14, 1203).

In this presentation, Prof. Hu will discuss these recent findings from his group, including design, synthesis, and performance of these novel superstructured materials for energy conversion and storage.