CZTS(Cu_(2)ZnSnS_(4))is a quaternary semiconductor that is environmentally friendly,less expensive.In this paper,we report on the optimization and fabrication of CZTS-based heterojunction nanodevices for bifunctional ...CZTS(Cu_(2)ZnSnS_(4))is a quaternary semiconductor that is environmentally friendly,less expensive.In this paper,we report on the optimization and fabrication of CZTS-based heterojunction nanodevices for bifunctional applications such as solar cells and photodetectors.CZTS thin films were deposited on top of(Molybdenum)Mo-coated glass substrates via RF sputtering at 100 and 200 W.Rapid thermal processing(RTP)was used at 300,400,and 500℃temperatures.Cd S(cadmium sulphide)was deposited on CZTS using a chemical bath deposition system with 3-and 5-min deposition times.Zn O(zinc oxide)and AZO(aluminium doped zinc oxide)layers were deposited using RF(radio frequency)sputtering to create the solar device.XRD confirms the formation of a tetragonal structure with increased crystallinity due to the use of RTP.Raman reveals the characteristic Raman shift peak associated with CZTS at 336 and 335 cm^(-1).The FESEM shows a relationship with RTP temperature.Surface features,including grain size,vary with RTP temperature.The ideality factor is nearly 2,indicating imperfection in the Mo/CZTS interface.Schottky barrier height estimates range from 0.6 to 0.7 e V.Absorbance and transmittance show a predictable fluctuation with RTP temperature.Photovoltaic device was built using the higher crystalline feature of CZTS in conjunction with Cd S deposited at 3 and 5 min.The efficiency of Cd S deposited after 3 and 5 min was 1.15 and 0.97 percent,respectively.Fabricated devices were used for wavelength-dependent photodetection.This work demonstrated self-powered photodetection.展开更多
Photonic neural networks(PNNs)of sufficiently large physical dimensions and high operation accuracies are envisaged as ideal candidates for breaking the major bottlenecks in the current artificial intelligence archite...Photonic neural networks(PNNs)of sufficiently large physical dimensions and high operation accuracies are envisaged as ideal candidates for breaking the major bottlenecks in the current artificial intelligence architectures in terms of latency,energy efficiency,and computational power.To achieve this vision,it is of vital importance to scale up the PNNs while simultaneously reducing the high demand on the dimensions required by them.The underlying cause of this strategy is the enormous gap between the scales of photonic and electronic integrated circuits.Here,we demonstrate monolithically integrated optical convolutional processors on thin film lithium niobate(TFLN)that harness inherent parallelism in photonics to enable large-scale programmable convolution kernels and,in turn,greatly reduce the dimensions required by subsequent fully connected layers.Experimental validation achieves high classification accuracies of 96%(86%)on the MNIST(Fashion-MNIST)dataset and 84.6%on the AG News dataset while dramatically reducing the required subsequent fully connected layer dimensions to 196×10(from 784×10)and 175×4(from 800×4),respectively.Furthermore,our devices can be driven by commercial field-programmable gate array systems;a unique advantage in addition to their scalable channel number and kernel size.Our architecture provides a solution to build practical machine learning photonic devices.展开更多
Innovative use of HfO_(2)-based high-dielectric-permittivity materials could enable their integration into few-nanometre-scale devices for storing substantial quantities of electrical charges,which have received wides...Innovative use of HfO_(2)-based high-dielectric-permittivity materials could enable their integration into few-nanometre-scale devices for storing substantial quantities of electrical charges,which have received widespread applications in high-storage-density dynamic random access memory and energy-efficient complementary metal-oxide-semiconductor devices.During bipolar high electric-field cycling in numbers close to dielectric breakdown,the dielectric permittivity suddenly increases by 30 times after oxygen-vacancy ordering and ferroelectric-to-nonferroelectric phase transition of near-edge plasma-treated Hf_(0.5)Zr_(0.5)O_(2) thin-film capacitors.Here we report a much higher dielectric permittivity of 1466 during downscaling of the capacitor into the diameter of 3.85μm when the ferroelectricity suddenly disappears without high-field cycling.The stored charge density is as high as 183μC cm^(−2) at an operating voltage/time of 1.2 V/50 ns at cycle numbers of more than 10^(12) without inducing dielectric breakdown.The study of synchrotron X-ray micro-diffraction patterns show missing of a mixed tetragonal phase.The image of electron energy loss spectroscopy shows the preferred oxygen-vacancy accumulation at the regions near top/bottom electrodes as well as grain boundaries.The ultrahigh dielectric-permittivity material enables high-density integration of extremely scaled logic and memory devices in the future.展开更多
Understanding the proton dynamic behavior in inorganic materials has long been a topic of intense fascination[1],especially in the field of electrochemical energy storage[2].One of the examples is the research of prot...Understanding the proton dynamic behavior in inorganic materials has long been a topic of intense fascination[1],especially in the field of electrochemical energy storage[2].One of the examples is the research of proton transport in transition metal oxides,which dates back to 1971[3]when RuO_(2) was discovered to be capable of storing protons via reversible redox reactions[4].In aqueous electrolytes,the thin film RuO_(2) electrode exhibits a surface pseudocapacitive behavior[5],which could be modified by the structural water in its hydrated form due to the facile Grotthuss hopping mode of protons along the established hydrogen bonds inside the bulk phase[6].Soon later,Goodenough et al.reported the capacitor-like behavior of amorphous MnO_(2)·xH_(2)O electrode in an aqueous KCl electrolyte[7],and further studies on the hydrated MnO_(2) electrodes prepared by sol-gel processes have soon discovered that the intercalation of protons from aqueous electrolytes plays an indispensable role in the charge storage mechanism[8].In recent years,the research interest on rechargeable aqueous batteries has fueled the renaissance of mechanistic study of proton transport in transition metal oxides[9],which can operate as cathodes or anodes via a topotactic insertion mechanism similar to that in Li-ion batteries[10].However,due to the challenges for experimental detection of local chemical environments of the inserted protons,a comprehensive understanding of proton dynamic behavior in these electrodes remains largely lacking.展开更多
High-quality antiferromagnetic(AFM)θ-phase manganese nitride(MnN)films were successfully grown on MgO(001)substrates by plasma-assisted molecular beam epitaxy.Structural analysis confirms the high-quality MnN film ha...High-quality antiferromagnetic(AFM)θ-phase manganese nitride(MnN)films were successfully grown on MgO(001)substrates by plasma-assisted molecular beam epitaxy.Structural analysis confirms the high-quality MnN film has a tetragonal distortion with a c/a ratio of~0.98.The film exhibits exceptional stability in both aqueous and ambient conditions,which is a crucial factor for practical applications.Electrical transport reveals its metallic behavior with an upturn at low temperatures,which could be attributed to the Kondo effect originated from nitrogen vacancy-induced magnetic impurities.Room temperature exchange bias has been demonstrated in a MnN/CoFeB heterostructure,verifying the AFM ordering of MnN.Considering its high Néel temperature~650 K,superior stability,and low-cost,this work highlights the epitaxial MnN films as a promising candidate for AFM spintronic applications.展开更多
Amorphous Ga_(2)O_(3)(a-Ga_(2)O_(3))thin films were prepared on flexible polyimide,rigid quartz glass,and Si substrates via radio frequency magnetron sputtering at room temperature.The effect of oxygen/Ar flow rate ra...Amorphous Ga_(2)O_(3)(a-Ga_(2)O_(3))thin films were prepared on flexible polyimide,rigid quartz glass,and Si substrates via radio frequency magnetron sputtering at room temperature.The effect of oxygen/Ar flow rate ratio on the structure,optical property,surface morphology,and chemical bonding properties of the a-Ga_(2)O_(3) films was investigated.Results show that the average optical transmittance of the a-Ga_(2)O_(3) films is over 80%within the wavelength range of 300-2000 nm.The extracted optical band gap of the a-Ga_(2)O_(3) films is increased from 4.97 eV to 5.13 eV with the increase in O_(2)/Ar flow rate ratio from 0 to 0.25,due to the decrease in concentration of oxygen vacancy defects in the film.Furthermore,the optical refractive index and surface roughness of the a-Ga_(2)O_(3) films are optimized when the O_(2)/Ar flow rate ratio reaches 0.25.X-ray photoelectron spectroscopy analysis also shows that the proportion of oxygen vacancies(VO)and Ga-O chemical bonds in the O 1s peak is gradually decreased with the increase in O_(2)/Ar flow rate ratio from 0 to 0.25,proving that increasing the O_(2)/Ar flow rate ratio during film growth can reduce the concentration of oxygen vacancy defects in a-Ga_(2)O_(3) films.In this case,a-Ga_(2)O_(3) with optimal properties can be obtained.This work provides a research basis for high-performance flexible and rigid deep ultraviolet solar-blind detection devices based on a-Ga_(2)O_(3) films.展开更多
The evolution of display backplane technologies has been driven by the relentless pursuit of higher form factor and superior performance coupled with lower power consumption.Current state-of-the-art backplane technolo...The evolution of display backplane technologies has been driven by the relentless pursuit of higher form factor and superior performance coupled with lower power consumption.Current state-of-the-art backplane technologies based on amorphous Si,poly Si,and IGZO,face challenges in meeting the requirements of next-generation displays,including larger dimensions,higher refresh rates,increased pixel density,greater brightness,and reduced power consumption.In this context,2D chalcogenides have emerged as promising candidates for thin-film transistors(TFTs)in display backplanes,offering advantages such as high mobility,low leakage current,mechanical robustness,and transparency.This comprehensive review explores the significance of 2D chalcogenides as materials for TFTs in next-generation display backplanes.We delve into the structural characteristics,electronic properties,and synthesis methods of 2D chalcogenides,emphasizing scalable growth strategies that are relevant to large-area display backplanes.Additionally,we discuss mechanical flexibility and strain engineering,crucial for the development of flexible displays.Performance enhancement strategies for 2D chalcogenide TFTs have been explored encompassing techniques in device engineering and geometry optimization,while considering scaling over a large area.Active-matrix implementation of 2D TFTs in various applications is also explored,benchmarking device performance on a large scale which is a necessary aspect of TFTs used in display backplanes.Furthermore,the latest development on the integration of 2D chalcogenide TFTs with different display technologies,such as OLED,quantum dot,and MicroLED displays has been reviewed in detail.Finally,challenges and opportunities in the field are discussed with a brief insight into emerging trends and research directions.展开更多
Visible and near-infrared photodetectors are widely used in intelligent driving,health monitoring,and other fields.However,the application of photodetectors in the near-infrared region is significantly impacted by hig...Visible and near-infrared photodetectors are widely used in intelligent driving,health monitoring,and other fields.However,the application of photodetectors in the near-infrared region is significantly impacted by high dark current,which can greatly reduce their performance and sensitivity,thereby limiting their effectiveness in certain applications.In this work,the introduction of a C60 back interface layer successfully mitigated back interface reactions to decrease the thickness of the Mo(S,Se)_(2)layer,tailoring the back-contact barrier and preventing reverse charge injection,resulting in a kesterite photodetector with an ultralow dark current density of 5.2×10^(-9)mA/cm^(2)and ultra-weak-light detection at levels as low as 25 pW/cm^(2).Besides,under a self-powered operation,it demonstrates outstanding performance,achieving a peak responsivity of 0.68 A/W,a wide response range spanning from 300 to 1600 nm,and an impressive detectivity of 5.27×10^(14)Jones.In addition,it offers exceptionally rapid response times,with rise and decay times of 70 and 650 ns,respectively.This research offers important insights for developing high-performance self-powered near-infrared photodetectors that have high responsivity,rapid response times,and ultralow dark current.展开更多
The early stages of crystallization and occurrence of surface wrinkling were investigated using poly(butadiene)-block-poly(ε-caprolactone)with an ordered lamellar structure.Direct evidence has demonstrated that surfa...The early stages of crystallization and occurrence of surface wrinkling were investigated using poly(butadiene)-block-poly(ε-caprolactone)with an ordered lamellar structure.Direct evidence has demonstrated that surface wrinkling precedes nucleation and crystal growth.This study examined the relationship between surface wrinkling,nucleation,and the formation of crystalline supramolecular structures using atomic force microscopy(AFM)and X-ray scattering measurements.Surface wrinkling is attributed to curving induced by accumulated stresses,including residual stress from the sample preparation and thermal stress during cooling.These stresses cause large-scale material flow and corresponding changes in the molecular conformations,potentially reducing the nucleation barrier.This hypothesis is supported by the rapid crystal growth observed following the spread of surface wrinkles.Additionally,the surface curving of the polymer thin film creates local minima of the free energy,facilitating nucleation.The nuclei subsequently grow into crystalline supramolecular structures by incorporating polymer molecules from the melt.This mechanism highlights the role of localized structural inhomogeneity in the early stages of crystallization and provides new insights into structure formation processes.展开更多
Quasi-one-dimensional(quasi-1D)van der Waals(vdWs)materials,such as ZrTe_(5),exhibit unique elec-trical properties and quantum phenomena,making them attractive for advanced electronic applications.However,large-scale ...Quasi-one-dimensional(quasi-1D)van der Waals(vdWs)materials,such as ZrTe_(5),exhibit unique elec-trical properties and quantum phenomena,making them attractive for advanced electronic applications.However,large-scale growth of ZrTe_(5) thin films presents challenges.We address this by employing sput-tering,a common semiconductor industry technique.The as-deposited ZrTe_(5) film is amorphous,and post-annealing induces a crystallization process akin to transition-metal dichalcogenides.Our study in-vestigates the electrical and optical properties during this amorphous-to-crystalline transition,reveal-ing insights into the underlying mechanism.This work contributes to the fundamental understanding of quasi-1D materials and introduces a scalable fabrication method for ZrTe_(5) which offers the possibility of fabricating unique future electronic and optical devices.展开更多
Transition metal borides(TMBs)are a new class of promising electrocatalysts for hydrogen generation by water splitting.However,the synthesis of robust all-in-one electrodes is challenging for practical applications.He...Transition metal borides(TMBs)are a new class of promising electrocatalysts for hydrogen generation by water splitting.However,the synthesis of robust all-in-one electrodes is challenging for practical applications.Herein,a facile solid-state boronization strategy is reported to synthesize a series of self-supported TMBs thin films(TMB-TFs)with large area and high catalytic activity.Among them,MoB thin film(MoB-TF)exhibits the highest activity toward electrocatalytic hydrogen evolution reaction(HER),displaying a low overpotential(η10=191 and 219 mV at 10 mA cm^(−2))and a small Tafel slope(60.25 and 61.91 mV dec^(−1))in 0.5M H_(2)SO_(4)and 1.0M KOH,respectively.Moreover,it outperforms the commercial Pt/C at the high current density region,demonstrating potential applications in industrially electrochemical water splitting.Theoretical study reveals that both surfaces terminated by TM and B atoms can serve as the active sites and the H*binding strength of TMBs is correlated with the p band center of B atoms.This work provides a new pathway for the potential application of TMBs in largescale hydrogen production.展开更多
The article entitled with OptoGPT:A foundation model for inverse design in optical multilayer thin film structures1,with doi:10.29026/oea.2024.240062,published in No.7,Vol.7,2024 of Opto-Electronic Advances,has attrac...The article entitled with OptoGPT:A foundation model for inverse design in optical multilayer thin film structures1,with doi:10.29026/oea.2024.240062,published in No.7,Vol.7,2024 of Opto-Electronic Advances,has attracted attention from many researchers.As a result,the authors received many requests on the possibility sharing their code,model,and dataset in the mentioned work.To facilitate the needs of the research community,the authors decide to make the code,model,and datasets of OptoGPT public,enabling broader utilization and further development of enhanced models.展开更多
Flexible thermoelectric thin films offer a promising avenue for the development of portable and sustainable flexible power supplies.However,a lack of thin films with excellent performance restricts their application i...Flexible thermoelectric thin films offer a promising avenue for the development of portable and sustainable flexible power supplies.However,a lack of thin films with excellent performance restricts their application in flexible thermoelectric devices.In this study,high-performance BiSbTe films are successfully prepared using a combination of magnetron sputtering and thermal diffusion.By optimizing carrier concentration to~4.47×10^(19)cm^(−3)and simultaneously realizing high carrier mobility of>120 cm^(2)·V^(−1)·s^(−1),an impressive room-temperature power factor of 24.13μW·cm^(−1)·K^(−2)is achieved in a Bi_(0.4)Sb_(1.6)Te_(3)thin film.The flexible Bi_(0.4)Sb_(1.6)Te_(3)thin film also demonstrates excellent bending resistance and stability(ΔR/R_(0)<5%,ΔS/S_(0)<5%,andΔS^(2)σ/S_(0)^(2)σ_(0)<10%)after 1000 bending cycles at a minimum bending radius of 6 mm.A flexible thin-film thermoelectric device assembled with p-type Bi_(0.4)Sb_(1.6)Te_(3)legs achieves a remarkable power output of~82.15 nW and a power density of~547.68μW·cm^(−2)under a temperature difference of 20 K.展开更多
The emergence of cesium lead halide perovskite materials stable at air opened new prospects for the optoelectronic industry.In this work we present an approach to fabricating a flexible green perovskite light-emitting...The emergence of cesium lead halide perovskite materials stable at air opened new prospects for the optoelectronic industry.In this work we present an approach to fabricating a flexible green perovskite light-emitting electrochemical cell(PeLEC)with a CsPbBr_(3)perovskite active layer using a highly-ordered silicon nanowire(Si NW)array as a distributed electrode integrated within a thin polydimethylsiloxane film(PDMS).Numerical simulations reveal that Si NWs-based distributed electrode aids the improvement of carrier injection into the perovskite layer with an increased thickness and,therefore,the enhancement of light-emitting performance.The X-ray diffraction study shows that the perovskite layer synthesized on the PDMS membrane with Si NWs has a similar crystal structure to the ones synthesized on planar Si wafers.We perform a comparative analysis of the light-emitting devices’properties fabricated on rigid silicon substrates and flexible Si NW-based membranes released from substrates.Due to possible potential barriers in a flexible PeLEC between the bottom electrode(made of a network of single-walled carbon nanotube film)and Si NWs,the electroluminescence performance and Ⅰ-V properties of flexible devices deteriorated compared to rigid devices.The developed PeLECs pave the way for further development of inorganic flexible uniformly light-emitting devices with improved properties.展开更多
We study the axisymmetric frictionless indentation problem of a piezoelectric semiconductor(PSC)thin film perfectly bonded to a semi-infinite isotropic elastic substrate by a rigid and insulating spherical indenter.Th...We study the axisymmetric frictionless indentation problem of a piezoelectric semiconductor(PSC)thin film perfectly bonded to a semi-infinite isotropic elastic substrate by a rigid and insulating spherical indenter.The Hankel integral transformation is first employed to derive the general solutions for the governing differential equations of the PSC film and elastic substrate.Then,using the boundary and interface conditions,the complicated indentation problem is reduced to numerically solve a Fredholm integral equation of the second kind.Numerical results are given to demonstrate the effects of semiconducting property,film thickness as well as Young’s modulus and Poisson’s ratio of the substrate on the indentation responses.The obtained findings will contribute to the establishment of indentation experiments for PSC film/substrate systems.展开更多
We investigated the influence of PEG on the surface morphology,photocatalytic performance,photovoltaic conversion efficiency(PCE),and performance in complex environments of TiO_(2)-PEG composite films.The PEG content ...We investigated the influence of PEG on the surface morphology,photocatalytic performance,photovoltaic conversion efficiency(PCE),and performance in complex environments of TiO_(2)-PEG composite films.The PEG content was varied to further optimize the comprehensive performance of the composite films.Using titanium isopropoxide as the main raw material,TiO_(2)-PEG sol was prepared via sol-gel method and coated on the surface of photovoltaic(PV)glass by spin coating.The surface morphology and crystalline phase of the TiO_(2)-PEG film were analyzed,and the effects of the TiO_(2)-PEG film on the photocatalytic performance,PCE,contact angle,and performance in complex environments of PV glass were studied.The experimental results show that under the specified experimental conditions,when 4 g PEG10000 is added,the comprehensive performance of the coated PV glass reaches its optimum,with an average transmittance of 91.73%at 550 nm.Using methylene blue(MB)dye degradation experiments,the degradation rate after 2 hours of xenon lamp irradiation reaches 98.15%.The photovoltaic conversion efficiency of the composite film reaches 16.33%,and the contact angle is 3.28°,indicating a superhydrophilic state.It is demonstrated that the appropriate amount of PEG can enhance the transmittance,self-cleaning performance,and photovoltaic conversion efficiency of coated PV glass.展开更多
The sulfur-fumigation process not only induces the chemical transformation of Lycium barbarum(Lb,a widely used traditional Chinese medicine)but also severely influences human health.Given the existing challenges like ...The sulfur-fumigation process not only induces the chemical transformation of Lycium barbarum(Lb,a widely used traditional Chinese medicine)but also severely influences human health.Given the existing challenges like the complex and time-consuming operation,as well as the high technical demands of the current detection methods for sulfur-fumed Lycium barbarum(SF-Lb),this paper employs a simple chemiresistor to carry out discrimination research between Lb and SF-Lb which have significant differences in volatolomics.The sensor is constructed by a conductive metal-organic framework(cMOF)thin film,Cu_(3)(HHTP)_(2),due to its abundant active sites,excellent electron transfer performance as well as the capacity to detect specific groups of volatile organic compounds(VOCs).Consequently,the response values of Cu_(3)(HHTP)_(2)-based sensor to 0.5 g SF-Lb(151.74%)are significantly higher than those to normal Lb(80.07%),identifying SF-Lb simply and rapidly with an accuracy of~100%.Our work investigates volatolomics of SF-Lb and establishes a new rapid discrimination method for sulfur-fumed traditional Chinese herbs.展开更多
The unidirectional flow of lymphatic fluid depends significantly on the valve structure within the lymphatic system,thus impacting tumor cell metastasis via the lymphatic system.However,existing microdevices for study...The unidirectional flow of lymphatic fluid depends significantly on the valve structure within the lymphatic system,thus impacting tumor cell metastasis via the lymphatic system.However,existing microdevices for studying tumor lymphatic metastasis have overlooked the impact of open-close valve structures on the lymphatic flow field.This paper presents a novel biomimetic lymphatic valve structure,which innovatively incorporates the thin-shell theory into the modeling of lymphatic-mimicking structures.Through finite element simulations,we have systematically analyzed the influence of valve thickness and elasticity on its deformation characteristics.Materials closely matching the actual properties of biological tissues are synthesized.And the soft-etching technique was used to fabricate lymphomimetic microchannels,which were then tested to evaluate their capability in intercepting unidirectional flow.The results showed that the lymphomimetic valve structure had no observable leaks and effectively intercepted unidirectional flow.Our study not only elucidates the mechanism of lymphatic circulation but also presents a dependable biomimetic model that could facilitate additional biological investigations and phenotypic drug screening.展开更多
Bismuth ferrite perovskite materials have recently attracted great attention because of their unique properties.In this study,Bi_(1-x)RE_(x)FeO_(3)(RE=La,Ce,Pr,Nd,Sm;x=0,0.05,0.1)thin films were deposited on glass sub...Bismuth ferrite perovskite materials have recently attracted great attention because of their unique properties.In this study,Bi_(1-x)RE_(x)FeO_(3)(RE=La,Ce,Pr,Nd,Sm;x=0,0.05,0.1)thin films were deposited on glass substrates via low-temperature sol-gel assisted spin coating procedure.It is found that in the presence of light rare-earth ions as the substitutions,the structural,morphological,and optical properties of the thin films are changed in the prepared thin films.We find that the thin films have rhombohedral structures,and from field emission scanning electron microscopy(FESEM)images,it is observed that the substitution of light rare-earth ions for Bi^(3+)affects the surface morphology and grain size of the BiFeO_(3)(BFO)thin film.Moreover,the optical properties of prepared films were investigated via UV-visible spectroscopy.For all samples,the bandgap energy values are between 1.22 and 1.65 eV.Also,the refractive index and extinction coefficient of samples are about 1.14-1.41 and 0.1-0.6,respectively.Photocatalytic properties of the samples were investigated by measuring the degradation of methylene blue(MB)dye under irradiation of sunlight.We find that the light rare-earth substituted BFO thin films have better photocatalytic activity compared to pure BiFeO_(3) thin film,the reason can be described as the band gap varied between 1.20 and 1.65 eV for different rare earth ions which directly influences the photocatalytic properties of the investigated samples.It is observed that the prepared thin films can remove between 37.18%and 69.14%of dye after 180 min of irradiation.This study confirms that prepared thin films are a suitable candidate for photocatalytic applications.展开更多
Electronics over flexible substrates offer advantages of flexibility, portability and low cost, and promising applications in the areas of energy, information, defense science and medical service. In recent years, tre...Electronics over flexible substrates offer advantages of flexibility, portability and low cost, and promising applications in the areas of energy, information, defense science and medical service. In recent years, tremendous progress has been witnessed in the development of flexible wearable devices that can be potentially massively deployed. Of particular interest are intelligent wearable devices, such as sensors and storage cells, which can be integrated by flexible magnetoelectronic devices based on magnetic thin films. To examine this further, the magnetic properties of FeNi thin films with different thicknesses grown on flexible graphene substrate are investigated at room temperature. The coercivity increases with increasing thicknesses of FeNi thin film, which can be attributed to the increase of grain size and decrease of surface roughness. Moreover, the thickness modulated magnetic property shows a magnetic anisotropy shift increase with varying thicknesses of FeNi thin film by using measurements based on ferromagnetic resonance, which further enhances the resonance frequency. In addition, the resonance peak is quite stable after bending it for ten cycles. The result is promising for the future design of flexible magnetoelectronic devices.展开更多
文摘CZTS(Cu_(2)ZnSnS_(4))is a quaternary semiconductor that is environmentally friendly,less expensive.In this paper,we report on the optimization and fabrication of CZTS-based heterojunction nanodevices for bifunctional applications such as solar cells and photodetectors.CZTS thin films were deposited on top of(Molybdenum)Mo-coated glass substrates via RF sputtering at 100 and 200 W.Rapid thermal processing(RTP)was used at 300,400,and 500℃temperatures.Cd S(cadmium sulphide)was deposited on CZTS using a chemical bath deposition system with 3-and 5-min deposition times.Zn O(zinc oxide)and AZO(aluminium doped zinc oxide)layers were deposited using RF(radio frequency)sputtering to create the solar device.XRD confirms the formation of a tetragonal structure with increased crystallinity due to the use of RTP.Raman reveals the characteristic Raman shift peak associated with CZTS at 336 and 335 cm^(-1).The FESEM shows a relationship with RTP temperature.Surface features,including grain size,vary with RTP temperature.The ideality factor is nearly 2,indicating imperfection in the Mo/CZTS interface.Schottky barrier height estimates range from 0.6 to 0.7 e V.Absorbance and transmittance show a predictable fluctuation with RTP temperature.Photovoltaic device was built using the higher crystalline feature of CZTS in conjunction with Cd S deposited at 3 and 5 min.The efficiency of Cd S deposited after 3 and 5 min was 1.15 and 0.97 percent,respectively.Fabricated devices were used for wavelength-dependent photodetection.This work demonstrated self-powered photodetection.
基金supported by the National Natural Science Foundation of China (Grant Nos.12192251,12334014,62335019,12134001,1230441812474378)+1 种基金the Quantum Science and Technology National Science and Technology Major Project(Grant No.2021ZD0301403)the Shanghai Municipal Science and Technology Major Project (Grant No.2019SHZDZX01)。
文摘Photonic neural networks(PNNs)of sufficiently large physical dimensions and high operation accuracies are envisaged as ideal candidates for breaking the major bottlenecks in the current artificial intelligence architectures in terms of latency,energy efficiency,and computational power.To achieve this vision,it is of vital importance to scale up the PNNs while simultaneously reducing the high demand on the dimensions required by them.The underlying cause of this strategy is the enormous gap between the scales of photonic and electronic integrated circuits.Here,we demonstrate monolithically integrated optical convolutional processors on thin film lithium niobate(TFLN)that harness inherent parallelism in photonics to enable large-scale programmable convolution kernels and,in turn,greatly reduce the dimensions required by subsequent fully connected layers.Experimental validation achieves high classification accuracies of 96%(86%)on the MNIST(Fashion-MNIST)dataset and 84.6%on the AG News dataset while dramatically reducing the required subsequent fully connected layer dimensions to 196×10(from 784×10)and 175×4(from 800×4),respectively.Furthermore,our devices can be driven by commercial field-programmable gate array systems;a unique advantage in addition to their scalable channel number and kernel size.Our architecture provides a solution to build practical machine learning photonic devices.
基金supported by the National Key Basic Research Program of China (2022YFA1402904)Basic Research Project of Shanghai Science and Technology Innovation Action (grant number 24CL2900900)the National Natural Science Foundation of China (grant number 61904034)
文摘Innovative use of HfO_(2)-based high-dielectric-permittivity materials could enable their integration into few-nanometre-scale devices for storing substantial quantities of electrical charges,which have received widespread applications in high-storage-density dynamic random access memory and energy-efficient complementary metal-oxide-semiconductor devices.During bipolar high electric-field cycling in numbers close to dielectric breakdown,the dielectric permittivity suddenly increases by 30 times after oxygen-vacancy ordering and ferroelectric-to-nonferroelectric phase transition of near-edge plasma-treated Hf_(0.5)Zr_(0.5)O_(2) thin-film capacitors.Here we report a much higher dielectric permittivity of 1466 during downscaling of the capacitor into the diameter of 3.85μm when the ferroelectricity suddenly disappears without high-field cycling.The stored charge density is as high as 183μC cm^(−2) at an operating voltage/time of 1.2 V/50 ns at cycle numbers of more than 10^(12) without inducing dielectric breakdown.The study of synchrotron X-ray micro-diffraction patterns show missing of a mixed tetragonal phase.The image of electron energy loss spectroscopy shows the preferred oxygen-vacancy accumulation at the regions near top/bottom electrodes as well as grain boundaries.The ultrahigh dielectric-permittivity material enables high-density integration of extremely scaled logic and memory devices in the future.
基金financial support from the National Natural Science Foundation of China(22109003)the Basic and Applied Basic Research Foundation of Guangdong Province(2023A1515011391)+1 种基金Soft Science Research Project of Guangdong Province(No.2017B030301013)the Major Science and Technology Infrastructure Project of Material Genome Big-science Facilities Platform supported by Municipal Development and Reform Commission of Shenzhen.
文摘Understanding the proton dynamic behavior in inorganic materials has long been a topic of intense fascination[1],especially in the field of electrochemical energy storage[2].One of the examples is the research of proton transport in transition metal oxides,which dates back to 1971[3]when RuO_(2) was discovered to be capable of storing protons via reversible redox reactions[4].In aqueous electrolytes,the thin film RuO_(2) electrode exhibits a surface pseudocapacitive behavior[5],which could be modified by the structural water in its hydrated form due to the facile Grotthuss hopping mode of protons along the established hydrogen bonds inside the bulk phase[6].Soon later,Goodenough et al.reported the capacitor-like behavior of amorphous MnO_(2)·xH_(2)O electrode in an aqueous KCl electrolyte[7],and further studies on the hydrated MnO_(2) electrodes prepared by sol-gel processes have soon discovered that the intercalation of protons from aqueous electrolytes plays an indispensable role in the charge storage mechanism[8].In recent years,the research interest on rechargeable aqueous batteries has fueled the renaissance of mechanistic study of proton transport in transition metal oxides[9],which can operate as cathodes or anodes via a topotactic insertion mechanism similar to that in Li-ion batteries[10].However,due to the challenges for experimental detection of local chemical environments of the inserted protons,a comprehensive understanding of proton dynamic behavior in these electrodes remains largely lacking.
文摘High-quality antiferromagnetic(AFM)θ-phase manganese nitride(MnN)films were successfully grown on MgO(001)substrates by plasma-assisted molecular beam epitaxy.Structural analysis confirms the high-quality MnN film has a tetragonal distortion with a c/a ratio of~0.98.The film exhibits exceptional stability in both aqueous and ambient conditions,which is a crucial factor for practical applications.Electrical transport reveals its metallic behavior with an upturn at low temperatures,which could be attributed to the Kondo effect originated from nitrogen vacancy-induced magnetic impurities.Room temperature exchange bias has been demonstrated in a MnN/CoFeB heterostructure,verifying the AFM ordering of MnN.Considering its high Néel temperature~650 K,superior stability,and low-cost,this work highlights the epitaxial MnN films as a promising candidate for AFM spintronic applications.
基金Research Project of Shenzhen Science and Technology Innovation Committee(JCYJ20180306170801080)。
文摘Amorphous Ga_(2)O_(3)(a-Ga_(2)O_(3))thin films were prepared on flexible polyimide,rigid quartz glass,and Si substrates via radio frequency magnetron sputtering at room temperature.The effect of oxygen/Ar flow rate ratio on the structure,optical property,surface morphology,and chemical bonding properties of the a-Ga_(2)O_(3) films was investigated.Results show that the average optical transmittance of the a-Ga_(2)O_(3) films is over 80%within the wavelength range of 300-2000 nm.The extracted optical band gap of the a-Ga_(2)O_(3) films is increased from 4.97 eV to 5.13 eV with the increase in O_(2)/Ar flow rate ratio from 0 to 0.25,due to the decrease in concentration of oxygen vacancy defects in the film.Furthermore,the optical refractive index and surface roughness of the a-Ga_(2)O_(3) films are optimized when the O_(2)/Ar flow rate ratio reaches 0.25.X-ray photoelectron spectroscopy analysis also shows that the proportion of oxygen vacancies(VO)and Ga-O chemical bonds in the O 1s peak is gradually decreased with the increase in O_(2)/Ar flow rate ratio from 0 to 0.25,proving that increasing the O_(2)/Ar flow rate ratio during film growth can reduce the concentration of oxygen vacancy defects in a-Ga_(2)O_(3) films.In this case,a-Ga_(2)O_(3) with optimal properties can be obtained.This work provides a research basis for high-performance flexible and rigid deep ultraviolet solar-blind detection devices based on a-Ga_(2)O_(3) films.
基金supported in part by the National Research Foundation of Korea Grant Number:RS-2024-00448809National Research Foundation of Korea Grant Number:RS-2025-00517255+1 种基金National Research Foundation of Korea Grant Number:No.2021M3H4A1A02056037supported by Basic Science Research Program through the National Research Foundation of Korean(NRF)funded by the Ministry of Education(2020R1A6A1A03040516).
文摘The evolution of display backplane technologies has been driven by the relentless pursuit of higher form factor and superior performance coupled with lower power consumption.Current state-of-the-art backplane technologies based on amorphous Si,poly Si,and IGZO,face challenges in meeting the requirements of next-generation displays,including larger dimensions,higher refresh rates,increased pixel density,greater brightness,and reduced power consumption.In this context,2D chalcogenides have emerged as promising candidates for thin-film transistors(TFTs)in display backplanes,offering advantages such as high mobility,low leakage current,mechanical robustness,and transparency.This comprehensive review explores the significance of 2D chalcogenides as materials for TFTs in next-generation display backplanes.We delve into the structural characteristics,electronic properties,and synthesis methods of 2D chalcogenides,emphasizing scalable growth strategies that are relevant to large-area display backplanes.Additionally,we discuss mechanical flexibility and strain engineering,crucial for the development of flexible displays.Performance enhancement strategies for 2D chalcogenide TFTs have been explored encompassing techniques in device engineering and geometry optimization,while considering scaling over a large area.Active-matrix implementation of 2D TFTs in various applications is also explored,benchmarking device performance on a large scale which is a necessary aspect of TFTs used in display backplanes.Furthermore,the latest development on the integration of 2D chalcogenide TFTs with different display technologies,such as OLED,quantum dot,and MicroLED displays has been reviewed in detail.Finally,challenges and opportunities in the field are discussed with a brief insight into emerging trends and research directions.
基金supported by the National Natural Science Foundation of China(No.52472225)the Science and Technology Plan Project of Shenzhen(No.20220808165025003),China。
文摘Visible and near-infrared photodetectors are widely used in intelligent driving,health monitoring,and other fields.However,the application of photodetectors in the near-infrared region is significantly impacted by high dark current,which can greatly reduce their performance and sensitivity,thereby limiting their effectiveness in certain applications.In this work,the introduction of a C60 back interface layer successfully mitigated back interface reactions to decrease the thickness of the Mo(S,Se)_(2)layer,tailoring the back-contact barrier and preventing reverse charge injection,resulting in a kesterite photodetector with an ultralow dark current density of 5.2×10^(-9)mA/cm^(2)and ultra-weak-light detection at levels as low as 25 pW/cm^(2).Besides,under a self-powered operation,it demonstrates outstanding performance,achieving a peak responsivity of 0.68 A/W,a wide response range spanning from 300 to 1600 nm,and an impressive detectivity of 5.27×10^(14)Jones.In addition,it offers exceptionally rapid response times,with rise and decay times of 70 and 650 ns,respectively.This research offers important insights for developing high-performance self-powered near-infrared photodetectors that have high responsivity,rapid response times,and ultralow dark current.
基金the National Natural Science Foundation of China(Nos.U2032101 and 11905306)the National Key Research and Development Project of China(No.2022YFB2402602).
文摘The early stages of crystallization and occurrence of surface wrinkling were investigated using poly(butadiene)-block-poly(ε-caprolactone)with an ordered lamellar structure.Direct evidence has demonstrated that surface wrinkling precedes nucleation and crystal growth.This study examined the relationship between surface wrinkling,nucleation,and the formation of crystalline supramolecular structures using atomic force microscopy(AFM)and X-ray scattering measurements.Surface wrinkling is attributed to curving induced by accumulated stresses,including residual stress from the sample preparation and thermal stress during cooling.These stresses cause large-scale material flow and corresponding changes in the molecular conformations,potentially reducing the nucleation barrier.This hypothesis is supported by the rapid crystal growth observed following the spread of surface wrinkles.Additionally,the surface curving of the polymer thin film creates local minima of the free energy,facilitating nucleation.The nuclei subsequently grow into crystalline supramolecular structures by incorporating polymer molecules from the melt.This mechanism highlights the role of localized structural inhomogeneity in the early stages of crystallization and provides new insights into structure formation processes.
基金supported by the JSPS KAKENHI(Grant Nos.21H05009,22K20474,and 24K00915)the Murata Science Foundation+1 种基金supported by the Commissioned Research(No.JPJ012368C03701)of the National Institute of Information and Communications Technology(NICT),Japansupport from the Hirose Foundation and Iketani Science and Technology Foundation.
文摘Quasi-one-dimensional(quasi-1D)van der Waals(vdWs)materials,such as ZrTe_(5),exhibit unique elec-trical properties and quantum phenomena,making them attractive for advanced electronic applications.However,large-scale growth of ZrTe_(5) thin films presents challenges.We address this by employing sput-tering,a common semiconductor industry technique.The as-deposited ZrTe_(5) film is amorphous,and post-annealing induces a crystallization process akin to transition-metal dichalcogenides.Our study in-vestigates the electrical and optical properties during this amorphous-to-crystalline transition,reveal-ing insights into the underlying mechanism.This work contributes to the fundamental understanding of quasi-1D materials and introduces a scalable fabrication method for ZrTe_(5) which offers the possibility of fabricating unique future electronic and optical devices.
基金National Natural Science Foundation of China,Grant/Award Number:52172058Outstanding Youth Fund of Natural Science Foundation of Inner Mongolia Autonomous Region,Grant/Award Number:2023JQ15+4 种基金Fundamental Research Funds for the Inner Mongolia Normal University,Grant/Award Numbers:2022JBBJ010,2022JBTD008Major Project Cultivation Fund for the Inner Mongolia Normal University,Grant/Award Number:2020ZD01Funds for Reform and Development of Local Universities Supported by The Central Government(Cultivation of First-Class Disciplines in Physics)Postdoctoral Fellowship Program of CPSF,Grant/Award Number:GZB20240101China Postdoctoral Science Foundation,Grant/Award Number:2024M750304.
文摘Transition metal borides(TMBs)are a new class of promising electrocatalysts for hydrogen generation by water splitting.However,the synthesis of robust all-in-one electrodes is challenging for practical applications.Herein,a facile solid-state boronization strategy is reported to synthesize a series of self-supported TMBs thin films(TMB-TFs)with large area and high catalytic activity.Among them,MoB thin film(MoB-TF)exhibits the highest activity toward electrocatalytic hydrogen evolution reaction(HER),displaying a low overpotential(η10=191 and 219 mV at 10 mA cm^(−2))and a small Tafel slope(60.25 and 61.91 mV dec^(−1))in 0.5M H_(2)SO_(4)and 1.0M KOH,respectively.Moreover,it outperforms the commercial Pt/C at the high current density region,demonstrating potential applications in industrially electrochemical water splitting.Theoretical study reveals that both surfaces terminated by TM and B atoms can serve as the active sites and the H*binding strength of TMBs is correlated with the p band center of B atoms.This work provides a new pathway for the potential application of TMBs in largescale hydrogen production.
文摘The article entitled with OptoGPT:A foundation model for inverse design in optical multilayer thin film structures1,with doi:10.29026/oea.2024.240062,published in No.7,Vol.7,2024 of Opto-Electronic Advances,has attracted attention from many researchers.As a result,the authors received many requests on the possibility sharing their code,model,and dataset in the mentioned work.To facilitate the needs of the research community,the authors decide to make the code,model,and datasets of OptoGPT public,enabling broader utilization and further development of enhanced models.
基金supported by the Natural Science Foundation of Shandong Province(No.ZR2023ME001),China Postdoctoral Science Foundation(No.2023M732609)the Doctoral Research Initiation Fund of Weifang University(No.2023BS01).
文摘Flexible thermoelectric thin films offer a promising avenue for the development of portable and sustainable flexible power supplies.However,a lack of thin films with excellent performance restricts their application in flexible thermoelectric devices.In this study,high-performance BiSbTe films are successfully prepared using a combination of magnetron sputtering and thermal diffusion.By optimizing carrier concentration to~4.47×10^(19)cm^(−3)and simultaneously realizing high carrier mobility of>120 cm^(2)·V^(−1)·s^(−1),an impressive room-temperature power factor of 24.13μW·cm^(−1)·K^(−2)is achieved in a Bi_(0.4)Sb_(1.6)Te_(3)thin film.The flexible Bi_(0.4)Sb_(1.6)Te_(3)thin film also demonstrates excellent bending resistance and stability(ΔR/R_(0)<5%,ΔS/S_(0)<5%,andΔS^(2)σ/S_(0)^(2)σ_(0)<10%)after 1000 bending cycles at a minimum bending radius of 6 mm.A flexible thin-film thermoelectric device assembled with p-type Bi_(0.4)Sb_(1.6)Te_(3)legs achieves a remarkable power output of~82.15 nW and a power density of~547.68μW·cm^(−2)under a temperature difference of 20 K.
基金the Russian Science Foundation Project No.22-79-10286,https://rscf.ru/project/22-7910286/(synthesis of perovskites, PeLEC fabrication)the Russian Science Foundation Project No.23-79-01151 for NW/PDMS membrane fabrication and PeLEC characterization+1 种基金the Ministry of Science and Higher Education of the Russian Federation (Project. FZSR-2020-0007 within the framework of state task no. 075-03-2020-097/1) for the support of SWCNT synthesisthe Ministry of Science and Higher Education of the Russian Federation (Project FSRM-2022-0007) for NW fabrication
文摘The emergence of cesium lead halide perovskite materials stable at air opened new prospects for the optoelectronic industry.In this work we present an approach to fabricating a flexible green perovskite light-emitting electrochemical cell(PeLEC)with a CsPbBr_(3)perovskite active layer using a highly-ordered silicon nanowire(Si NW)array as a distributed electrode integrated within a thin polydimethylsiloxane film(PDMS).Numerical simulations reveal that Si NWs-based distributed electrode aids the improvement of carrier injection into the perovskite layer with an increased thickness and,therefore,the enhancement of light-emitting performance.The X-ray diffraction study shows that the perovskite layer synthesized on the PDMS membrane with Si NWs has a similar crystal structure to the ones synthesized on planar Si wafers.We perform a comparative analysis of the light-emitting devices’properties fabricated on rigid silicon substrates and flexible Si NW-based membranes released from substrates.Due to possible potential barriers in a flexible PeLEC between the bottom electrode(made of a network of single-walled carbon nanotube film)and Si NWs,the electroluminescence performance and Ⅰ-V properties of flexible devices deteriorated compared to rigid devices.The developed PeLECs pave the way for further development of inorganic flexible uniformly light-emitting devices with improved properties.
基金supported by the National Natural Science Foundation of China(Nos.12072209,U21A20430,12192211,12472155)the S&T Program of Hebei(225676162GH).
文摘We study the axisymmetric frictionless indentation problem of a piezoelectric semiconductor(PSC)thin film perfectly bonded to a semi-infinite isotropic elastic substrate by a rigid and insulating spherical indenter.The Hankel integral transformation is first employed to derive the general solutions for the governing differential equations of the PSC film and elastic substrate.Then,using the boundary and interface conditions,the complicated indentation problem is reduced to numerically solve a Fredholm integral equation of the second kind.Numerical results are given to demonstrate the effects of semiconducting property,film thickness as well as Young’s modulus and Poisson’s ratio of the substrate on the indentation responses.The obtained findings will contribute to the establishment of indentation experiments for PSC film/substrate systems.
基金Funded by the Project of Guangxi Science and Technology(No.ZY24212061)the Project of Guangxi Science and Technology Major Program(No.AA24263054)the Project of Beihai Science and Technology(No.202379002)。
文摘We investigated the influence of PEG on the surface morphology,photocatalytic performance,photovoltaic conversion efficiency(PCE),and performance in complex environments of TiO_(2)-PEG composite films.The PEG content was varied to further optimize the comprehensive performance of the composite films.Using titanium isopropoxide as the main raw material,TiO_(2)-PEG sol was prepared via sol-gel method and coated on the surface of photovoltaic(PV)glass by spin coating.The surface morphology and crystalline phase of the TiO_(2)-PEG film were analyzed,and the effects of the TiO_(2)-PEG film on the photocatalytic performance,PCE,contact angle,and performance in complex environments of PV glass were studied.The experimental results show that under the specified experimental conditions,when 4 g PEG10000 is added,the comprehensive performance of the coated PV glass reaches its optimum,with an average transmittance of 91.73%at 550 nm.Using methylene blue(MB)dye degradation experiments,the degradation rate after 2 hours of xenon lamp irradiation reaches 98.15%.The photovoltaic conversion efficiency of the composite film reaches 16.33%,and the contact angle is 3.28°,indicating a superhydrophilic state.It is demonstrated that the appropriate amount of PEG can enhance the transmittance,self-cleaning performance,and photovoltaic conversion efficiency of coated PV glass.
基金supported by the National Natural Science Foundation of China(Nos.22205121,22494633,22401281)CAS President's International Fellowship for Visiting Scientists(No.2024VBC0002)+2 种基金the research fund of State Key Laboratory of Mesoscience and Engineering(Nos.MESO-23-A07,MESO-23-T02,MESO-24-A01)First-class Discipline Construction Project(Chemistry)in Higher Education Institutions of Ningxia(Ningxia Normal University)Engineering Research Center of Liupanshan(No.HGZD22-27).
文摘The sulfur-fumigation process not only induces the chemical transformation of Lycium barbarum(Lb,a widely used traditional Chinese medicine)but also severely influences human health.Given the existing challenges like the complex and time-consuming operation,as well as the high technical demands of the current detection methods for sulfur-fumed Lycium barbarum(SF-Lb),this paper employs a simple chemiresistor to carry out discrimination research between Lb and SF-Lb which have significant differences in volatolomics.The sensor is constructed by a conductive metal-organic framework(cMOF)thin film,Cu_(3)(HHTP)_(2),due to its abundant active sites,excellent electron transfer performance as well as the capacity to detect specific groups of volatile organic compounds(VOCs).Consequently,the response values of Cu_(3)(HHTP)_(2)-based sensor to 0.5 g SF-Lb(151.74%)are significantly higher than those to normal Lb(80.07%),identifying SF-Lb simply and rapidly with an accuracy of~100%.Our work investigates volatolomics of SF-Lb and establishes a new rapid discrimination method for sulfur-fumed traditional Chinese herbs.
基金supported by National Natural Science Foundation of National Key Research and Development Program of China(2020YFB2009002).
文摘The unidirectional flow of lymphatic fluid depends significantly on the valve structure within the lymphatic system,thus impacting tumor cell metastasis via the lymphatic system.However,existing microdevices for studying tumor lymphatic metastasis have overlooked the impact of open-close valve structures on the lymphatic flow field.This paper presents a novel biomimetic lymphatic valve structure,which innovatively incorporates the thin-shell theory into the modeling of lymphatic-mimicking structures.Through finite element simulations,we have systematically analyzed the influence of valve thickness and elasticity on its deformation characteristics.Materials closely matching the actual properties of biological tissues are synthesized.And the soft-etching technique was used to fabricate lymphomimetic microchannels,which were then tested to evaluate their capability in intercepting unidirectional flow.The results showed that the lymphomimetic valve structure had no observable leaks and effectively intercepted unidirectional flow.Our study not only elucidates the mechanism of lymphatic circulation but also presents a dependable biomimetic model that could facilitate additional biological investigations and phenotypic drug screening.
基金The financial support of the Research Council of Damghan University with grant number 856207。
文摘Bismuth ferrite perovskite materials have recently attracted great attention because of their unique properties.In this study,Bi_(1-x)RE_(x)FeO_(3)(RE=La,Ce,Pr,Nd,Sm;x=0,0.05,0.1)thin films were deposited on glass substrates via low-temperature sol-gel assisted spin coating procedure.It is found that in the presence of light rare-earth ions as the substitutions,the structural,morphological,and optical properties of the thin films are changed in the prepared thin films.We find that the thin films have rhombohedral structures,and from field emission scanning electron microscopy(FESEM)images,it is observed that the substitution of light rare-earth ions for Bi^(3+)affects the surface morphology and grain size of the BiFeO_(3)(BFO)thin film.Moreover,the optical properties of prepared films were investigated via UV-visible spectroscopy.For all samples,the bandgap energy values are between 1.22 and 1.65 eV.Also,the refractive index and extinction coefficient of samples are about 1.14-1.41 and 0.1-0.6,respectively.Photocatalytic properties of the samples were investigated by measuring the degradation of methylene blue(MB)dye under irradiation of sunlight.We find that the light rare-earth substituted BFO thin films have better photocatalytic activity compared to pure BiFeO_(3) thin film,the reason can be described as the band gap varied between 1.20 and 1.65 eV for different rare earth ions which directly influences the photocatalytic properties of the investigated samples.It is observed that the prepared thin films can remove between 37.18%and 69.14%of dye after 180 min of irradiation.This study confirms that prepared thin films are a suitable candidate for photocatalytic applications.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 51901163 and 12104171)the Fundamental Research Funds for the Central Universities (Grant No. 2021XXJS025)the Natural Science Foundation of Hubei Province (Grants No. 2024AFB888)。
文摘Electronics over flexible substrates offer advantages of flexibility, portability and low cost, and promising applications in the areas of energy, information, defense science and medical service. In recent years, tremendous progress has been witnessed in the development of flexible wearable devices that can be potentially massively deployed. Of particular interest are intelligent wearable devices, such as sensors and storage cells, which can be integrated by flexible magnetoelectronic devices based on magnetic thin films. To examine this further, the magnetic properties of FeNi thin films with different thicknesses grown on flexible graphene substrate are investigated at room temperature. The coercivity increases with increasing thicknesses of FeNi thin film, which can be attributed to the increase of grain size and decrease of surface roughness. Moreover, the thickness modulated magnetic property shows a magnetic anisotropy shift increase with varying thicknesses of FeNi thin film by using measurements based on ferromagnetic resonance, which further enhances the resonance frequency. In addition, the resonance peak is quite stable after bending it for ten cycles. The result is promising for the future design of flexible magnetoelectronic devices.
