Conventional nanomaterials in electrochemical nonenzymatic sensing face huge challenge due to their complex size-, surface-, and composition-dependent catalytic properties and low active site density. In this work, we designed a single-atom Pt supported on Ni­(OH)2 nanoplates/nitrogen-doped graphene (Pt1/Ni­(OH)2/NG) as the first example for constructing a single-atom catalyst based electrochemical nonenzymatic glucose sensor. The resulting Pt1/Ni­(OH)2/NG exhibited a low anode peak potential of 0.48 V and high sensitivity of 220.75 μA mM–1 cm–2 toward glucose, which are 45 mV lower and 12 times higher than those of Ni­(OH)2, respectively. The catalyst also showed excellent selectivity for several important interferences, short response time of 4.6 s, and high stability over 4 weeks. Experimental and density functional theory (DFT) calculated results reveal that the improved performance of Pt1/Ni­(OH)2/NG could be attributed to stronger binding strength of glucose on single-atom Pt active centers and their surrounding Ni atoms, combined with fast electron transfer ability by the adding of the highly conductive NG. This research sheds light on the applications of SACs in the field of electrochemical nonenzymatic sensing.

Single-atom catalysts (SACs) are attracting extensive attention due to their incredibly catalytic activity and selectivity, high utilization of metal atoms, and obvious cost reduction. The unique ordered porous materials (OPMs) are promising carriers for stabilizing single atoms due to their large surface areas and uniformly tunable pore sizes. Meantime, the geometric and electronic structures of single-atom metals can be tuned by the interaction between the single-atoms (SAs) and OPMs to enhance the catalytic activity of SACs. The SACs based on OPMs, such as zeolites, metal-organic frameworks, and ordered mesoporous materials, have been developing fast recently. Herein, we review recent advancements on structural feature, synthetic strategy, characterization technique, and catalytic applications of OPMs-based SACs. The opportunities and challenges about SAs/OPMs are also provided to develop the novel catalysts with superior catalytic performances in the future.

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It is important to develop new energy storage and conversion technology to mitigate the energy crisis for the sustainable development of human society. In this study, free-standing porous nitrogen-doped carbon fiber (PN-CF) membranes were obtained from the pyrolysis of Zn–MOF-74/polyacrylonitrile (PAN) composite fibers, which were fabricated in situ by an electrospinning technology. The resulting free-standing fibers can be cut into membrane disks and directly used as an anode electrode without the addition of any binder or additive. The PN-CFs showed great reversible capacities of 210 mAh g−1 at a current density of 0.05 A g−1 and excellent cyclic stability of 170.5 mAh g−1 at a current density of 0.2 A g−1 after 600 cycles in sodium ion batteries (SIBs). The improved electrochemical performance of PN-CFs can be attributed to the rich porous structure derived by the incorporation of Zn–MOF-74 and nitrogen doping to promote sodium ion transportation.