Fig. 2.

(a) Arrhenius plot $k_{\text{obs}}=A{e}^{-E_a/RT}$ for Br₃AA degradation without (□) and with (○) graphite over time at 15°C, 25°C, 35°C, and 45°C in darkness. The calculated Br₃AA decay activation energies (E_a) were 13.6±2.2 and 25.7±3.2 kcal·mol⁻¹ with/without graphite. (b) Solid state ¹³C multiCP/MAS NMR spectra of PCM₀ (Li et al., 2019), PCM_-OH (Li et al., 2019), and PCM_-COOH. All the spectra were recorded at a spinning speed of 14 kHz with a 90° ¹³C pulse-length of 4 μs. (c) Pseudo first-order Br₃AA degradation rate constants with PCM₀, PCM_-OH, and PCM_-COOH. (d) Optimized structures for reactants, transition state, and products of (i) Reaction (1) and (ii) Reaction (2) based on DFT simulation.