Alternating current properties of bulk- and nanosheet-graphitic carbon nitride compacts at elevated temperatures

Abstract

g-C3N4 in bulk- and nanosheet-form display stable, weakly temperature dependent AC properties from 400 to 50 °C.

Fluorine-Rich, Hydrophobic Graphite Fluoride with Improved Charge Transport/Storage Properties Produced by Gamma Irradiation

“…This shape suggests that the samples are highly insulating. The AC conductivities σ AC (Figure b) increase as the frequency ( f ) increases (data at ∼10 5 Hz were removed as they are an instrumental artifact similarly observed in our laboratory on other highly insulating materials , ). At f ≈ 10 2 Hz where the f -independent (static) conductivity is assumed, the 200/400 kGy GFs are more conducting than the 0 kGy sample (10 –9 vs 10 –10 S·cm –1 ), although both are still insulating.…”

“…All GF samples similarly show the mass loss of <0.1 wt % at T < 150 °C (Figure 1c, vs ∼2 wt % in g-C 3 N 4 , 29,30 ) presumably due to a tiny amount of physisorbed water. The major mass loss occurs at T > 450 °C, with the peak T m (±standard deviation) from the derivative curve of 626 ± 2 °C (vs 625 °C in ref 16) ascribed to GF decomposition.…”

“…The different presentations of the AC properties (see eqs S1–S12) point out that the samples show improved charge transport/storage properties, dependent on the γ-dose and the measurement temperature (RT to 200 °C). The results are compared to those of graphitic carbon nitride (g-C 3 N 4 ), an N-containing, C-based, aromatic van der Waals layer material. , The hydrophilic g-C 3 N 4 showed AC properties dependent on atmospheric water, , thereby contrasting with the hydrophobic GF. Our work demonstrates the use of γ-irradiation as a chemical-free tool to modify the electrical properties of GF, while also reporting/deducing some important fundamental parameters such as relaxation time, activation energy, effective dimension of charge carriers, and so on.…”

“…T-dependent electrical properties at 10 6 Hz of the GF samples at different doses of γ-irradiation: (a) log σ AC , (b) ε′, and (c) tan δ; (d) M″(T) × 1000 (shown here for the 400 kGy sample at selected frequencies), (f) n, and (g) J.Panel (e) shows the Arrhenius plot (including that of the nonirradiated GF). Black symbols are the nonirradiated g-C 3 N 4 taken from Maluangnont et al29,30…”

Surfactant-free 2D/2D Pd/g-C3N4 for enhanced photocatalytic CO2 reduction

“…S1†). 25 Under ultrasound, the PdCl 4 2− precursor first reacted with CO to form [Pd 2 (μ-CO) 2 Cl 4 ] 2− , which was subsequently reduced to metallic Pd. 19 Simultaneously, CO selectively bound with the Pd(111) facets, resulting in Pd NSs.…”