The hairy Co/CoP–HNC derived from common MOFs exhibits excellent tri-functional catalytic activity for ORR, OER, and HER in an alkaline solution.

5Ni-Fe layered double hydroxide (LDH) was regarded one of the best catalysts for oxygen evolution reaction (OER), yet bridging the relationship between LDH nanostructure and OER performance remains a big challenge. Unlike other hydrothermal reaction produced Ni-Fe layered double hydroxides, we adopted a simple separate nucleation and the aged steps method to investigate the effect of crystallinity and intercalated anions of LDH on OER performance and found that improving the crystallinity and the 10 size of NiFe-LDH by increasing the aged temperature led to the decrease of OER activity. While changing the interlayer spacing of LDH from 8.04 Å to 7.69 Å through introducing more CO 3 2-to replace NO 3 -causes the reduction of OER activity. These were probably attributed to more exposed active sites, lower charger transferring resistance, and better exchange ability with OH -in interlamination. Based on above observation and the consequent optimizations, a very-low onset overpotential (~240 mV) and Tafel 15 slope value (33.6 mV/dec) (in 0.1 mol/L KOH) room-temperature synthetic NiFe LDH was achieved. This work proposed the strategy for the rational design of LDHs for further enhancement of OER electrochemical activity, i.e. by decreasing the size and crystallinity of NiFe-LDH and introducing more NO 3 -between layers.

Polymers are important precursors for the fabrication of carbon materials. Herein, halogenated polymers are explored as precursors for the synthesis of high‐quality carbon materials via alkaline dehalogenation. It is found that the halogen elements (F, Cl) connecting to vinylidene units are highly reactive so that dehalogenation can take place a few seconds at room temperature by simple hand grinding in the presence of strong inorganic alkaline. Furthermore, the halogen element‐leaving sites are shown to be susceptible to heteroatom doping (e.g., N doping) to become stable capacitive sites for charge storage (e.g., ions). By using a mixture of NaOEt and KOH as dehalogenation reagents, abundant hierarchical pores (macro/meso/micropores) in the resultant doped carbon matrix for fast mass transportation can be created. Very high capacitance (328 F g−1 at 0.5 A g−1) and rate capability (75.3% retention at 50 A g−1 and 62.5% retention at 100 A g−1) are observed for the newly developed halogenated polymer‐derived doped carbon materials.

A nickel–cobalt oxides supported on Co/N decorated graphene composite was prepared with excellent bifunctional oxygen catalytic performance.