查看更多>>摘要：Visible light-driven environmentally friendly ZnO semiconductor for durable photocatalytic disinfection and purification of drinking water is very promising.However,the high requirement in ultraviolet absorption and rapid recombination velocity of the photogenerated electron-hole severely hamper the sustainable implementation of ZnO in photocatalysis.Herein,by one"two birds with one stone"strategy,Fe-doping ZnO por-ous nanosheets(Fe-ZnOPN)composed of ultrafine nanoparticles can be constructed by hydrothermal synthesis of basic zinc carbonate and controlled low-temperature pyrolytic methods.By highly concentrated Fe-doping effect(＞7 wt％),the tailoring ZnO nanograin size(～10nm)and rich oxygen vacancy of catalyst were accessed by ion/vacancy diffusion and nanocrystal rear-rangement,superior to the ZnO porous nanosheets(～37 nm).The obtained Fe-ZnOPN were endowed with a larger specific surface area,improved visible light har-vesting ability,light response and separation of charge carriers.Such characters allowed the resulting catalyst to afford a 100％bactericidal efficiency against Pseudomonas aeruginosa and Staphylococcus aureus under visible light irradiation(＞420 nm).Impressively,the Fe-ZnOPN could show practical disinfection ability in different water resources and multiple reuse ability.The mechanism study revealed that excellent photocatalytic disinfection perfor-mance of Fe-ZnOPN correlated with the in situ generated active oxidative substances,destruction of bacterial biofilm and resulting nucleic acids leakage,thereby causing irre-versible physical damage.This study provided a new ref-erence for designing environmentally friendly photocatalytic sterilization materials and disinfectants,which can be used in the practical disinfection of drinking water.
查看更多>>摘要：Crystallization,while a common process in nature,remains one of the most mysterious phenomena.Understanding its physical mechanisms is essential for obtaining high-quality crystals.Typically,crystals grown by thermal evaporation or sublimation nucleate the sub-strate facing the evaporation source.Here,a novel vapor micro-turbulence mass transport mechanism in the growth process of ultrathin BiOCl single crystals has been revealed.In this mechanism,the precursor vapor bypasses the solid substrate,forming micro-turbulent vaporizing flows to nucleate on the surface of the substrate facing away from the evaporation source.Considering nucleation kinetics,fast shear flows are known to cause secondary nucleation,increasing nucleation quantity while decreasing the final size of the crystals.Thus,the nucleation and growth process of BiOCl crystals are controlled by adjusting the micro-turbulence intensity to reduce shear flow energy and dilate phase distribution,resulting in BiOCl crystals with uniform distribution and regular shape.Subsequent structural and morphological characterization confirms the high crystallization quality of the obtained crystals,and the performance of the constructed solar-blind photodetectors is comparable to that of similar devices.These findings contribute to a deeper understanding of vapor mass transport and crystal growth techniques and may be useful for applications related to metal oxide crystals.
查看更多>>摘要：The emergence of all-inorganic perovskite CsPbBr3 has ignited significant interest in optoelectronic devices,However,CsPbBr3 thin film-based photodetectors face performance limitations due to grain boundaries and defect density.To address these challenges,we introduce a novel type Ⅱ heterojunction photodetector utilizing CsPbBr3 microwires(MWs)and CdS nanoribbons(NBs).Remarkably,this photodetector exhibits exceptional char-acteristics:a high on/off current ratio(1.07 × 10 5),a responsivity of up to 1.35 × 10 4 A·W-1,specific detec-tivity of 5.94 x 1015 Jones,external quantum efficiency of 2.83 × 10 4％and rapid response/recovery time(400 μs/3 ms).These superior performances stem from the excep-tional crystalline quality of CsPbBr3 MWs and CdS NBs,coupled with the establishment of a type Ⅱ band alignment at their interface.This configuration enables efficient car-rier separation while suppressing recombination.Impor-tantly,1D CsPbBr3 MW/CdS NB heterojunction photodetectors demonstrate reliable imaging capabilities under visible light illumination.Our findings present an innovative solution for high-performance perovskite-based photodetectors,holding promise for future commercial applications.
查看更多>>摘要：Two-dimensional materials are widely consid-ered to be highly promising for the development of pho-todetectors.To improve the performance of these devices,researchers often employ techniques such as defect engi-neering.Herein,pressure is employed as a clean and novel means to manipulate the structural and physical properties of EuSbTe3,an emerging two-dimensional semiconductor.The experimental results demonstrate that the structural phase transformation of EuSbTe3 occurs under pressure,with an increase in infrared reflectivity,a band gap closure,and a metallization at pressures.Com-bined with X-ray diffraction(XRD)and Raman charac-terizations,it is evident that the pressure-driven transition from semiconductor Pmmn phase to metallic Cmcm phase causes the disappearance of the charge density wave.Furthermore,at a mild pressure,approximately 2 GPa,the maximum photocurrent of EuSbTe3 is three times higher than that at ambient condition,suggesting an untapped potential for various practical applications.
查看更多>>摘要：Recently,application-oriented strain sensor has been intensively investigated in the fields of human motion detection,personalized health management and portable medical diagnosis.Despite significant efforts in improving its sensitivity and linear sensing range,devel-oping the wearable strain sensor with stable signal remains a challenge.Herein,we proposed an ideal hybrid material with nearly zero temperature coefficient resistance(TCR)for temperature-insensitive strain sensing:the silver nanostructures(AgNTs)were introduced to coat the gra-phene foam(GrF)conformably by hydrothermal growth.The nanoscaled metal additives(TCR＞0)not only endow GrF(TCR＜0)with high electrical stability(TCR≈-0.3 ×10-3 ℃-1),but also offer the hybrid system additional structural elasticity,potential for next-generation of portable,stretchable and reliable devices.The resultant AgNTs@GrF hybrid material has been processed into a piezoresistive sensor with excellent sensing accuracy(strain error＜2.7％),satisfactory gauge factor(GF)of 227,wide sensing range up to 90％and good cyclic sta-bility(＞3000 cycles).Moreover,our strain sensor can be easily mounted on human skin as an epidermal device for reliable detection of electrophysiological stimuli,thus showing a great promising in practical wearable applications.
查看更多>>摘要：Flexible composites with negative permittivity have a very broad development prospect in flexible elec-tronics and wearable devices.Currently,how to control the negative permittivity except for from their intrinsic prop-erties of components is still a challenge.In this study,the negative permittivity and frequency dispersion were adjusted by changing the heat treatment temperature.Polyvinylidene fluoride(PVDF)was selected as the flexi-ble matrix and reduced graphene oxide(rGO)as the functional filler to prepare rGO/PVDF membranous com-posites.The negative permittivity was observed in rGO/PVDF composites film,and the effect of heat treatment temperature on the negative permittivity was further stud-ied.It indicated that a higher heat treatment temperature contributed to the formation of conductive network,so as to obtaining negative permittivity.When the molding temperature was 70 ℃,the negative permittivity spectrum conformed to the Drude model was only observed in the composites with 35 wt％content of rGO.After the heat treatment temperature reached 180 ℃,when the content of rGO decreased to 25 wt％,the composites film achieved negative permittivity(～-10),which had a low-fre-quency dispersion in the test frequency range.The negative permittivity of in composites can be regulated by adjusting the heat treatment temperature,which promotes the appli-cation and development of flexible metamaterials in underwater sensing and detection,etc.
Stanley AbbeyHanhwi JangBrakowaa FrimpongVan Quang Nguyen...
5975-5984页
查看更多>>摘要：Switchable conductivity in elementary semi-conducting materials has a high potential for the design of diodes,transistors and energy conversion technolo-gies.However,the ability to utilize their physical properties is dependent on doping within the carrier density transition temperature.Single-crystal tellurium has a high Seebeck coefficient and intrinsic p-n-p conduction at room temperature and therefore,is not suitable for thermoelectric applications.We demonstrate that the addition of isovalent Se lowers the Fermi level to achieve a stable p-type conductivity with a high band degeneracy near the valence band.We observed shifts in the n-p transition temperature below the intrinsic conductivity at 470 K based on changes in stoichiom-etry and carrier concentration above 1017 cm-3.In addition,the high thermal conductivity is significantly reduced with the increase in Se alloying due to the mass and strain fluctuations.This results in a moder-ately high zT of 0.4 at 673 K.
查看更多>>摘要：Flexible thermoelectrics provide a distinct solution for developing sustainable and portable power supplies.Inorganic/organic material compositing is an effective strategy to induce a significant enhancement of thermoelectric(TE)performance.However,the poor electrical performance of inorganic/organic material is attributed to the poor carrier transport between organic/inorganic interfaces induced by the low contribution of composited inorganic materials.Herein,we prepared a high room temperature figure-of-merit(ZT)value of～0.19 and high bending resistance(surviving 1200 bending cycles at the bending radius of 16.5 mm)of p-type poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate)(PEDOT:PSS)/Bi0.5Sb1.5Te3 free-standing composite film via a facile vacuum-assisted filtration approach.Com-positing Bi0.5Sb1.5Te3 nano-spherical particles into PEDOT:PSS results in the optimized interfacial contact and carrier concentration,leading to a high Seebeck coef-ficient of～43.79 pV·K-1.Accordingly,a high-power factor of～1.52 pW·cm-1·K-2 is achieved in the PED-OT:PSS/Bi0.5Sb1.5Te3 composite film at room temperature.In addition,the PEDOT:PSS/Bi0.5Sb1.5Te3 interfaces with phase boundaries,nanograins and point defects could fur-ther decrease the thermal conductivity to～0.20 W·m-1·K-1,leading to a high ZT value.Furthermore,a 6-leg free-standing film device was assembled,which provided an output power of 44.94 nW.This study demonstrates that free-standing organic/inorganic composite films are effec-tive power sources for wearable electronic products.
查看更多>>摘要：Benefiting from excellent mechanical properties and low density,cellular ceramic structures(CCSs)are competitive candidates as structural components.However,inherent brittleness from strong chemical bonds among atoms extremely impeded CCSs'application.Natural materials occupied outstanding strength and toughness simultaneously due to the dual-phase interpenetrated structure.Inspired by natural materials,it was proposed to fabricate coating covered and fulfilled polyurea/CCS interpenetrated composites(C/CCSs and B/CCSs)to cir-cumvent the brittleness of 3D-printed Al2O3 CCSs.It was demonstrated that polyurea coating had less effect on the compressive strength of C/CCSs but tremendously improved their energy-absorbing ability.The energy-ab-sorbing ability of C/CCSs was improved from 26.48-52.57 kJ·m-3 of CCSs to 1.04-1.89 MJ.m-3 because of the extended plateau stage.Furthermore,com-pressive strength and energy-absorbing ability of B/CCSs were strengthened to 1.33-1.36 and 2.84-4.61 times of C/CCSs,respectively.Besides,failure mode of C/CCSs changed from localized deformation to fracturing entirely with the increase in relative density of CCSs inside,which was the same as that of CCSs.However,with the help of polyurea coating,C/CCSs were still intact at strains up to 60％,which would never fail catastrophically as CCSs at low strains.B/CCSs tended to fracture as a whole,which was not influenced by relative density of pristine CCSs.It was believed that this work provided a creative way to circumvent the brittleness of CCSs and improve their mechanical performances.
查看更多>>摘要：Cisplatin resistance is the main cause for the failure of cancer therapy.To solve the problem,we pro-posed to develop a novel human serum albumin(HSA)nanoplatform to integrate chemotherapy,photothermal therapy(PTT)and immunotherapy.To this end,we obtained a platinum compound(C5)with significant cytotoxicity in the cisplatin-resistant SKOV-3 cells(SKOV-3/DDP),and then innovatively constructed photo-sensitizer(indocyanine green(ICG))-encapsulated HSA-C5 complex nanoparticles(ICG@HSA-C5 NPs).The ICG@HSA-C5 NPs exhibited excellent photothermal per-formances in vitro and in vivo.Importantly,the in vivo results revealed that HSA enhanced the antitumor effect of C5 and that the combination of chemotherapy and PTT could significantly inhibit cisplatin-resistant tumor growth and improved the targeting abilities of C5 and ICG,and reduced their side effects.We also confirmed that ICG@HSA-C5 NPs killed the SKOV-3/DDP cells via gasdermin E(GSDME)-mediated pyroptosis andpyroptosis-induced immune responses,thereby synergisti-cally leading to the death of the SKOV-3/DDP cells.
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