RESUMO
Twin boundary (TB) engineering provides exciting opportunities to tune the performance levels of metal-based electrocatalysts. However, the controllable construction of TB greatly relies on surfactants, blocking active sites, and electron transfer by surfactants. Here, a surfactant-free and facile strategy is proposed for synthesizing copper (Cu) nanocatalysts with dense hierarchical TB networks (HTBs) by the rapid thermal reductions in metastable CuO nanosheets in H2 . As revealed by in situ transmission electron microscopy, the formation of HTBs is associated with the fragmentation of nanosheets in different directions to generate abundant crystal nuclei and subsequently unconventional crystal growth through the collision and coalescence of nuclei. Impressively, the HTBs endow Cu with excellent electrocatalytic performance for direct nitrate-ammonia conversion, superior to that of Cu with a single-oriented TB and without TB. It is discovered that the HTBs induce the formation of compressive strains, thereby creating a synergistic effect of TBs and strains to efficiently tune the binding energies of Cu with nitrogen intermediates (i.e., NO2 *) and thus promote the tandem reaction process of NO3 - -to-NO2 - and subsequent NO2 - -to-NH3 electrocatalysis. This work demonstrates the crucial role of HTBs for boosting electrocatalysis via the synergistic effect of TBs and strains.
RESUMO
Euodia ruticarpa is a medicinal plant recorded in in Chinese Pharmacopeia. Here we report on the complete chloroplast genome sequence of Euodia ruticarpa. The chloroplast genome is 158,762 bp in size and includes two inverted repeat regions of 54,230 bp, which is separated by a large single-copy region of 86,267 bp and a small single copy region of 18,265 bp. A total of 131 genes were predicted, including 37 tRNA, 8 rRNA, and 86 protein-coding genes. Phylogenetic analysis placed Euodia ruticarpa under the family Rutaceae.