Flake boron nitride (BN) in large yield was successfully synthesized at low temperature from the combustion synthesized precursor. The precursor was prepared by a low-temperature (350 • C) combustion synthesis (LCS) method using nitric acid (HNO 3), urea (CO(NH 2) 2), boric acid (H 3 BO 3), and glucose (C 6 H 12 O 6 •H 2 O) as starting materials. The precursor consists of B 2 O 3 and amorphous carbon and the morphology is composed of blocks with average diameters of about 10 µm by statistical methods using SEM at different fields. Then BN was synthesized at 900 • C in NH 3 at a heating rate of 5 • C min −1. The as-prepared BN possesses a flake morphology and high specific surface area up to 936 m 2 g −1. It also has high density structural defects and abundant-NH 2 /-OH groups. The surface groups improve its water wettability and electronegativity, which contributes to the rapid and selective adsorption performance, especially towards the cationic dyes. When 4 mg of the sample was added into a 100 mL RhB solution with an initial concentration of 5 mg L −1 , 95% of the RhB was removed within 1 min and the adsorption capacity is 125 mg g −1. Importantly, the sample can be regenerated by heating at 400 • C in air.

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Photolysis of (E)-4-cyano-4'-(2-heptamethyltrisilanyl)stilbene (E)-3 in a medium polarity solvent (CH(2)Cl(2)) results in efficient intramolecular electron transfer, which converts the initial pi,pi excited state ((1)LE state) to the charge transfer (CT) excited state. The CT excited state fluorescesces, undergoes E,Z photoisomerization, and reacts with MeOH to produce hydrosilane 4 via Si-Si bond cleavage and protonation of the central silicon, as shown by deuterium labeling. The CT excited state assignments are consistent with the observed quadratic plots of 1/Phi(f) versus [MeOH] and 1/Phi(EZ)() versus [MeOH], which indicate that both the initial (1)LE state and the CT excited state are quenched by MeOH, with the CT excited state serving as the emissive state and the state primarily responsible for the E,Z photoisomerization. Although biacetyl triplet sensitized photolysis results in efficient E,Z isomerization, quenching of direct photolyses by azulene shows (Z)-3 is not a product of the lowest energy triplet excited state, populated from the CT state by back electron transfer. The azulene quenching also shows that hydrosilane 4 is formed from the same excited state that gives (Z)-3. The intermediacy of a complex of the CT excited state with MeOH accounts for the observed upward curvature in the plot of 1/Phi(SiH) vs 1/[MeOH]. The linear behavior of Phi(EZ)()/Phi(SiH) x [MeOH] versus 1/[MeOH] further suggests that this complex reacts with uncomplexed MeOH to give hydrosilane 4.