Precisely tailoring the electronic structure and surface chemistry of metal-free covalent triazine frameworks (CTFs) for efficient photoactivation of oxyanions is environmentally desirable but still challenging. Of interest to us in this work was to construct artificial defective accumulation sites into a CTF network (CTF-SD x ) to synchronously modulate both thermodynamic (e.g., band structure) and kinetic (e.g., charge separation/transfer/utilization and surface adsorption) behaviors and probe how the transformation affected the subsequent activation mechanism of peroxymonosulfate (PMS). With the incorporation of terminal cyano (−CN) groups and boron (B) dopants, the delocalized CTF-SD underwent a narrowed electronic energy gap for increased optical absorption as well as a downshifted valence band position for enhanced oxidation capacity. Moreover, the localized charge accumulation regions induced by the electron-withdrawing −CN groups facilitated the exciton dissociation process, while the adjacent electron-deficient areas enabled strong affinity toward PMS molecules. All of these merits impelled the photoactivation reaction with PMS, and a 15-fold enhancement of bisphenol-A (BPA) removal was found in the CTF-SD2/PMS/vis system compared with the corresponding pristine CTF system. Mechanistic investigations demonstrated that this system decomposed organics primarily through a singlet oxygen-mediated nonradical process, which originated from PMS oxidative activation over photoinduced holes initiated by an electron transfer process, thereby opening a new avenue for designing an efficient PMS activation strategy for the selective oxidation of organic pollutants.

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Developing a reasonable conductive structure is an effective way to construct supercapacitor electrode materials with high properties. Inspired by the way branches and stems accumulate and transfer nutrients, we fabricated hierarchical dendritic electrodes through a facile hydrothermal process to make highcapacity supercapacitors. Specifically, a self-supporting hierarchical ZnO/NiCo-LDH structure was created on carbon cloth substrates via simple processes. The hierarchical dendritic structure facilitated efficient charge transfer and active site exposure as well as the synergetic effect of providing the stacking of layered LDH nanosheets. This hierarchical ZnO/NiCo-LDH electrode possessed excellent capacitance (22808.9 mF•cm -2 at 2 mA•cm -2 ) and good retention rate (85.7 % capacity retention at 15 mA•cm -2 ), while the capacitance of CC@NiCo-LDH was only 1620.9 mF•cm -2 . This structure design provides a good prospect for high-efficiency electrochemical supercapacitors.

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