Hybrid supercapacitors promise battery-like energy with capacitor-like power. In practice, that promise keeps breaking at the electrode: designs trade capacity for slow kinetics, interfaces destabilize during cycling, and impressive gravimetric numbers collapse once areal and volumetric metrics are reported.
Our new review in The Chemical Record looks at metal–organic frameworks (MOFs), covalent organic frameworks (COFs), and framework-derived materials — a family that combines ordered porosity with programmable redox chemistry — and asks a deliberately narrow question: what actually survives the move from a three-electrode half-cell to a working two-electrode device?
A device-centered decision framework
Rather than surveying materials family by family, the review links building-block chemistry and topology to the things that decide device behavior: charge-storage mode, ion transport, electrode density, and dominant failure pathways. MOFs, COFs, composites, and derived phases are then benchmarked across aqueous, organic, ionic-liquid, and gel electrolytes on the same terms.
Mechanism assignment as a gate, not an afterthought
A recurring problem in this literature is storage mechanism inferred from material class alone. The review defines minimum diagnostics to separate the three contributions that routinely coexist in one electrode:
EDLC — reversible ion adsorption, no Faradaic transfer.
Surface / near-surface redox pseudocapacitance — fast, interface-confined charge transfer.
Battery-like behavior — diffusion-limited, bulk-phase processes.
CV scaling and current separation, GCD signatures, EIS features, and operando or in situ evidence are treated as the evidence base — not as optional supporting figures.
Conductivity and stability strategies
As-synthesized frameworks are frequently poor electronic conductors with incomplete active-site utilization and limited hydrolytic stability. The review synthesizes four levers for closing that gap: percolation-network design, pore-access engineering, conformal interface stabilization, and controlled reconstruction or derivatization.
Thin-film interface engineering receives particular attention, with atomic layer deposition (ALD) discussed as a representative conformal approach. Notably, complete coverage is not always required — partial coverage can slow degradation without imposing severe transport penalties, provided the film is thin enough to leave pore entrances open. ALD is framed as complementary to framework chemistry rather than competing with it: its value lies in bridging molecularly designed frameworks to practical electrodes.
Fair comparison
The review closes with a degradation-mitigation map and a fair-comparison checklist that prioritizes realistic mass loading, electrode density, and areal and volumetric metrics — the same argument this group has been making elsewhere. Disclose the operating conditions, or the comparison cannot be trusted.
Read the review
Aupama V., Kao-ian W., Pornprasertsuk R., Sivagurunathan A.T., Kim D.-H., Theerthagiri J., Choi M.Y., Chou H.-H., Kheawhom S. Crystalline framework electrodes for hybrid supercapacitors: device-oriented design from metal–organic and covalent organic frameworks to practical hybrids. The Chemical Record 26 (2026) e70158. DOI 10.1002/tcr.70158