Depolarization of Li-rich Mn-based oxide via electrochemically active Prussian blue interface providing superior rate capability

The high-rate cyclability of Li-rich Mn-based oxide(LMO)is highly limited by the electrochemical polarization resulting from the slow kinetic of the Li2MnO3 phase.Herein,the Prussian blue(PB)coating layer with specific redox potential is introduced as a functionalized interface to overcome the side effect and the escaping of O on the surface of LMO,especially its poor rate capability.In detail,the PB layer can restrict the large polarization of LMO by sharing overloaded current at a high rate due to the synchronous redox of PB and LMO.Consequently,an enhanced high rate performance with capacity retention of 87.8%over 300 cycles is obtained,which is superior to 50.5%of the pristine electrode.Such strategies on the high-rate cyclability of Li-rich Mn-based oxide compatible with good low-rate performances may attract great attention for pursuing durable performances.

White light emission in 0D halide perovskite[(CH_(3))_(3)S]_(2)SnCl_(6)·H_(2)O crystals through variation of doping ns2 ions

With the rapid development of white LEDs,the research of new and efficient white light emitting materials has attracted increasing attention.Zero dimensional(0D)organic–inorganic hybrid metal halide perovskites with superior luminescent property are promising candidates for LED application,due to their abundant and tailorable structure.Herein,[(CH_(3))_(3)S]_(2)SnCl_(6)・H_(2)O is synthesized as a host for dopant ions Bi^(3+)and Sb^(3+).The Sb^(3+)doped,or Bi^(3+)/Sb^(3+)co-doped,[(CH_(3))3S]_(2)SnCl_(6)・H_(2)O has a tunable optical emission spectrum by means of varying dopant ratio and excitation wavelength.As a result,we can achieve single-phase materials suitable for emission ranging from cold white light to warm white light.The intrinsic mechanism is examined in this work,to clarify the dopant effect on the optical properties.The high stability of title crystalline material,against water,oxygen and heat,makes it promising for further application.

Cu-catalyzed regioselective diborylation of 1,3-enynes for the efficient synthesis of 1,4-diborylated allenes

Borylation of 1,3-enynes with bis(boronate)compounds often ends up with the formation of hydroborylated products,leaving the diborylation of 1,3-enynes for the formation of 1,4-diborylated allenes to be challenging.Herein,a copper-catalyzed chemo-,regio-,and stereo-selective diborylation of 1,3-enynes for the efficient construction of 1,4-diborylated allenes under base-free conditions was reported.A wide range of 1,3-enynes bearing various functional groups can participant in the reaction and afforded the corresponding 1,4-diborylated allenes in good to excellent yields,which was enabled by the protocol of Bpin to BF3K conversion.the borylcopper species was supposed to selectively attack the C-C triple bond of the 1,3-enynes.

Lactonization of dyes promoted by a coordination cage facilitates cavity-induced chromism as ion mobile detector

Dye molecules often change colors(so-called “chromism”) according to the environment variation. However, they are rarely induced by a catalytic amount of cavity. Through encapsulation in the cavity of a porous coordination cage(PCC-2), Rhodamine B(1) is transformed from red quinonoid form(1q) into colorless lactone form(1l) in aprotic polar solutions. The μ4-OH groups in the cavity of PCC-2 are shown to stabilize the uncommon zwitterion intermediate(1z), followed by converting to 1l, thus accelerating the equilibrium. The chromism is catalyzed by 0.25 mol% of PCC-2, and the reaction rate is improved by 80,400times. 1@PCC-2 can be further fabricated to a sol-gel that exhibits ion recognition properties. The resulting encapsulation and stabilization of an unconventional intermediate by a catalytic amount of the coordination cage provides fundamental insights into molecular isomerization and has potential use in chemical sensing.

Repurposing organic semiconducting nanomaterials to accelerate clinical translation of NIR-II fluorescence imaging

Optical imaging possesses important implications for early disease diagnosis,timely disease treatment,and basic medical as well as biological research.Compared with the traditionary near-infrared(NIR-I)window(650-950 nm)optical imaging,the emerging second near-infrared(NIR-II)window optical imaging technology owns the great superiorities of non-invasiveness,nonionizing radiation,and real-time dynamic imaging with the low biological interference,can significantly improve the tissue penetration depth and detection sensitivity,thus expecting to achieve accurate and precise diagnosis of major diseases.Inspired by the conspicuous superiorities,an increasing number of versatile NIR-II fluorophores have been legitimately designed and engineered for precisely deep-tissue mapping-mediated theranostics of life-threatening diseases.Organic semiconducting nanomaterials(OSNs)are derived from organic conjugated molecules withπ-electron delocalized skeletons,which show greatly preponderant prospects in the biomedicine field due to the excellent photoelectric property,tunable energy bands,and fine biocompatibility.In this review,the superiorities of NIR-II fluorescence imaging using OSNs for brilliant visualization various of diseases,including tongue cancer,ovarian cancer,osteosarcoma,bacteria or pathogens infection,kidney dysfunction,rheumatoid arthritis,liver injury,and cerebrovascular function,are emphatically summarized.Finally,the reasonable prospects and persistent efforts for repurposing OSNs to facilitate the clinical translation of NIR-II fluorescence phototheranostics are outlined.

A MOF-to-MOF conversion assisted formation of hierarchical hollow Zn-Co_(1-x)S/C@C composite for efficient potassium-ion storage

Hollow structured composite can enhance the structural stability of metal sulfide anode by accommodating its volume variation,while the performance is still hindered by its poor electron/ion conductivity.Herein,we develop a hier-archical hollow structure to achieve superior electrochemical performance,from which a MOF-to-MOF conversion is utilized to generate hollow Zn-Co_(1-x)S/C composite followed with additional carbon coating layer.For potassium storage,as-prepared hollow Zn-Co1.xS/C@C composite displays high capacities of 375 mA h g^(-1)after 100 cycles at 0.2 A g^(-1)and 201 mA h g^(-1)after 500 cycles at 1 A g^(-1).Moreover,it also manifests outstanding rate capability of 200 mA h g^(-1)at 10 A g^(-1),outperforming hollow Co_(1-x)S@C and majority of the reported cobalt-based anodes.With illustration by kinetics analysis and theoretical calculation,both of Zn doping and internal carbon matrix are conductive to promote the charge transportation ability of Co_(1-x)S,thus accounting for the good cycling behavior and excellent rate capacity of hierarchical hollow Zn-Co1.xS/C@C composite.

Boosting Stable and Fast Potassium Storage of Iron Sulfide through Rational Yolk-Shell Design and Ni Doping

Metal sulfides have been regarded as promising anodes for potassium-ion batteries(PIBs)due to their high theoretical capacities,while the performance is limited by their intrinsic poor conductivity and large volume fluctuation during the insertion/extraction of large potassium ion.Herein,the battery performance of iron sulfide anode is significantly enhanced through yolk-shell(Y-S)structure design and nickel doping,aiming to realize good structure stability and superior electron/ion transportation.For potassium storage,as-prepared Y-S Ni-FeS_(2)@C shows excellent cyclic performance and sustains high capacities of 328 mA h g^(-1)after 100 cycles at 0.2 A g^(-1)and 226 mA h g^(-1)after 1000 cycles at 1 A g^(-1).Especially,it displays a superior rate capacity of 200 mA h g^(-1)at 20 A g^(-1),higher than that of Y-S FeS_(2)@C and most as-reported metal sulfide anodes for PIBs.The experimental analysis and theoretical calculation illuminate the effect of Ni-doping on decreasing the particle size of iron sulfide and enhancing the ion/electron transport ability,thus accounting for the exceptional rate capability of Y-S Ni-FeS_(2)@C composite.

Manipulating intermolecular interactions for ultralong organic phosphorescence

Ultralong organic phosphorescence(UOP)materials have received considerable attention in the field of organic optoelectronics due to their long lifetime,high exciton utilization,large Stokes shift,and so on.Great advancements have been achieved through manipulating intermolecular interactions for high-performance UOP materials in recent years.This review will discuss the influence of various intermolecular interactions,includingπ-πinteractions,n-πinteractions,halogen bonding,hydrogen bonding,coordinative bonding,and ionic bonding on phosphorescent properties at room temperature,respectively.We summarize the rule of manipulating intermolecular interactions for UOP materials with superior phosphorescent properties.This review will provide a guideline for developing new UOP materials with superior phosphorescent properties for potential applications in organic electronics and bioelectronics.

Monodispersed SWNTs Assembled Coating Layer as an Alternative to Graphene with Enhanced Alkali-ion Storage Performance

Graphene coating is commonly used to improve the performance of electrode materials,while its steric hindrance effect hampers fast ion transport with compromised rate capability.Herein,a unique single-walled carbon nanotubes(SWNTs)coating layer,as an alternative to graphene,has been developed to improve the battery behavior of iron-based anodes.Benefiting from the structure merits of mesoporous SWNTs layer for fast electron/ion transport and hollow Fe_(3)O_(4) for volume accommodation,as-prepared Fe_(3)O_(4)@SWNTs exhibited excellent lithium storage performance.It delivers a high capacity,excellent rate capability,and long lifespan with capacities of 582 mA·h·g^(-1) at 5 A·g^(-1) and 408 mA·h·g^(-1) at 8 A·g^(-1) remained after 1000 cycles.Such performance is better than graphene-coated Fe_(3)O_(4) and other SWNT-Fe_(3)O_(4) architectures.Besides,SWNTs coating is also used to improve the sodium and potassium storage performance of FeSe_(2).The kinetics analysis and ex-situ experiment further reveal the effect of SWNTs coating for fast electron/ion transfer kinetics and good structure stability,thus leading to the superior performance of SWNTs-coated composites.

Dual-function perovskite light-emitting/sensing devices for optical interactive display

Interactive display devices integrating multiple functions have become a development trend of display technology.The excellent luminescence properties of perovskite quantum dots(PQDs)make it an ideal luminescent material for the next generation of wide-color gamut displays.Here we design and fabricate dual-function light-sensing/displaying light-emitting devices based on PQDs.The devices can display information as an output port,and simultaneously sense outside light signals as an input port and modulate the display information in a non-contact mode.The dual functions were attributed to the device designs:(1)the hole transport layer in the devices also acts as the light-sensing layer to absorb outside light signals;(2)the introduced hole trapping layer interface can trap holes originating from the light-sensing layer,and thus tune the charge transport properties and the light-emitting intensities.The sensing and display behavior of the device can be further modulated by light signals with different time and space information.This fusion of sensing and display functions has broad prospects in non-contact interactive screens and communication ports.