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A green aloe-vera gel contains small tissues (as capillaries), which easily upload Ca2+/In3+ species (upon adding in a solution) so as to form a hybrid complex and conduct a local carbothermic reaction (on heating) in the capillaries, forming a nanohybrid C-CaIn2O4, small core–shells of a tunable carbon-shell of a few molecular layers. Thin C-CaIn2O4 plates (15–20 nm thickness) thus were grown preferentially in (200) facets in a tetragonal crystal structure on a mixed gel which was burnt in camphor in air. The shell thickness was thermally etched down, δ = 3 → 0.5 nm, by post-heating at 400–600 °C in air. It finely tailors dielectric properties on account of interfaces, conducting networks, multiple surfaces, and O2– vacancies/twins (induced in a deoxidizing carbon) with effectively enhanced “e––h+” ion pairs useful for supercapacitors and other devices. In a proposed model, the CaIn2O4 bonds over C-sp2 via O2– in polygons in a network of a 2D-interface Ca2+/In3+–O–C (δ ≥ 0.5 nm), which, when heating, exists (≤1% mass) well up to 600 °C in air. A regular monolayer is very critical for feeding a huge dielectric permittivity εr(s) ∼ 6.9 × 106 on a moderate conductivity σdc ≤ 0.8 × 10–4 S·cm–1 at frequency ω → 0. After relaxing rapidly, a fairly steady εr = 7.6 × 103 lasts of yet a usefully large value over ω ≥ 102 Hz. A wide plateau spans in a steady σac ∼ 0.8 × 10–4 S·cm–1 over ω ≤ 103 Hz, before booting it up progressively by nearly two orders on higher ω in a frequency modulated ionic conductor. The “e––h+” pairs in a conductive network govern the conduction process over uneven and dynamic potential wells. A network as disrupts in thicker shells no longer feeds such large εr values.

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