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We have demonstrated that nanoporous gold (AuNPore) is an efficient catalyst to promote the selective diboration of methylenecyclopropanes (MCPs) in a heterogeneous manner. Notably, the diboration takes place via a regioselective cleavage of the distal bond of the cyclopropane ring exclusively by AuNPore without using any additives. The experimental results and computational studies of the mechanism indicate that the present diboration proceeds through the formation of a relatively stable trimethylenemethane intermediate on the AuNPore surface with increased negative charges on trimethylene carbons, giving rise to the subsequent diboration selectively.

In this study, Ce ions were doped into the crystal lattice of TNTs and bonded to O, which resulted in the generation of CeO2 and expansion of the lattice defects of TNTs. Then, TNTs and Ce doped TNTs (Ce-TNTs) were coated on the surface of bamboo fibre materials by layer-by-layer self-assembly to refine the flame retardant performance of the materials. Scanning electron micrographs (SEM) and energy disperse spectrum (EDS) analysis indicated that the TNTs and Ce-TNTs were uniformly distributed on the surface of the bamboo fibre materials, and the Ti content reached ∼3.90 wt% and ∼3.70 wt%, respectively. Results from the cone calorimeter test showed that the flame retardant performance of the bamboo fibre materials was enhanced after the TNTs were coated on the surface of the materials (TNTs@Fibre). When Ce-TNTs were used as substitute for TNTs, the flame retardant performance of the Ce-TNTs@Fibre materials was further improved. The TTI and FPI were prolonged to 39.7s and 0.073 m2 s/kW, and the av-HRR and THR were reduced to 126.9 kW/m2 and 35.54 MJ/m2 respectively. Moreover, pSEA, TSP and pSPR were decrease to 292.5 m2/kg, 3.70 m2 and 0.039 m2/s. DSC and TG results demonstrated that the TNTs and Ce-TNTs enhanced the both thermostability and thermo oxidative stability of the materials.