Construction of robust coupling interface between MoS2 and nitrogen doped graphene for high performance sodium ion batteries

As a layered inorganic material,MoS2 has recently attracted intensive attention as anode for sodium ion batteries(SIBs).However,this anode is plagued with low electronic conductivity,serious volume expansion and sluggish kinetics,resulting in capacity fading and poor rate performance.Herein,we develop an interface engineering strategy to substantially enhance the sodium storage performance of MoS2 by incorporating layered MoS2 into three dimensional N-doped graphene scaffold.The strong coupling-interface between MoS2 and N-doped graphene scaffold can not only stabilize the MoS2 structure during sodium insertion/extraction processes,but also provide plenty of anchor sites for additional surface sodium storage.The 3D MoS2@N-doped graphene composite as anode for SIBs performs an outstanding specific capacity of 667.3 mA h g^-1 at 0.2 A g^-1,a prolonged stability with a capacity retention of 94.4%after 140cycles and excellent rate capability of 445 mA h g^-1 even at a high rate of 10 A g^-1.We combined experiment and theoretical simulation to further disclose the interaction between MoS2 and N-doped graphene,adsorption and diffusion of sodium on the composite and the corresponding sodium storage mechanism.This study opens a new door to develop high performance SIBs by introducing the interface engineering technique.

Discovery and development of tricyclic matrinic derivatives as anti-diabetic candidates by AMPKαactivation

We found compound 12N-p-trifluoromethylbenzenesulfonyl matrinane(1)was a potent anti-diabetic agent.Thirty-five tricyclic matrinic derivatives were synthesized and determined for their stimulatory effects on glucose consumption in L6 myotubes,taking 1 as the lead.In high-fat diet(HFD)and STZ induced diabetic mice,9a significantly lowers blood glucose,improves glucose tolerance,and especially alleviates diabetic nephropathy and islet damage.Mechanism study indicates that 9a simultaneously targets mitochondrial complex I to increase AMP/ATP ratio,as well as liver kinase B1(LKB1)and calcium/calmodulindependent protein kinase(Ca MKK),which synergistically activates AMPKαand then stimulates glucose transporter 4(GLUT4)membrane translocation and 2-deoxyglucose(2-DG)uptake to exert anti-diabetic efficacy.Therefore,compound 9a with a novel structure is a promising anti-diabetic candidate with the advantage of multiple-target mechanism,worthy of further investigation.

Overcoming power efficiency limitation of white fluorescence light-emitting diodes via multilevel-hydrogen-bond matrix

High power efficiency and low efficiency roll-off at practical luminance are two requirements for new-generation energy-saving lighting technologies,which are still bottlenecks of thermally activated delayed fluorescence(TADF)white organic light-emitting diodes(WOLED),despite the advantages of TADF materials and devices in low cost and high sustainability.Herein,we developed a spiro phosphine oxide host named SSOXSPO,which can form multiple and multidirectional intermolecular hydrogen bonds(IHB).The resulted multilevel IHB network integrates long-range ordered and short-range disordered alignments for suppressing triplet-polaron quenching(TPQ)and triplet-triplet annihilation(TTA).Electronic characteristics of SSOXSPO matrix are further regulated,leading to the optimal exciton allocation through balancing energy and charge transfer.As consequence,using SSOXSPO as host,the single-emissive-layer TADF WOLEDs realized the record performance,including ultralow operation voltage as∼4.0 V,power efficiency beyond fluorescent tube(70.1 lm W−1)and negligible external quantum efficiency roll-off(3%)at 1000 nits for indoor lighting.This work demonstrates that multiple interplays supported by host matrixes in TADF WOLEDs can facilitate the synergistic effects of TADF emitters on 100%exciton utilization.