Materials for devices

  • Article
    | Open Access

    Resistive switching usually occurs by the formation of conducting filaments in the direction of current flow. Here the authors study an intriguing type of volatile metal-to-insulator resistive switching in (La,Sr)MnO3, which occurs by the formation of an insulating barrier perpendicular to the current.

    • Pavel Salev
    • , Lorenzo Fratino
    •  & Ivan K. Schuller
  • Article
    | Open Access

    TENG suffers from two fundamental limitations: high output impedance and low charge transfer. Herein, these limitations are circumvented by leveraging the opposite-charge-enhancement effect and transistor-like device design, thereby achieving the instantaneous power density over 10 MW/m2 at the low frequency of ~ 1 Hz.

    • Hao Wu
    • , Steven Wang
    •  & Yunlong Zi
  • Article
    | Open Access

    Phase transition brings a plethora of exotic phenomena and intriguing effects such as spin and charge frustration. However, the phase transition order is not always explicit. Here, the authors discover phase transition frustration near a tricritical composition point in ferroelectric Pb(Zr,Ti)O3.

    • Xian-Kui Wei
    • , Sergei Prokhorenko
    •  & Zuo-Guang Ye
  • Article
    | Open Access

    The limit of X-ray detection is an important figure of merit for X-ray detectors, yet the suitability of method adopted from Currie’s 1968 paper and the following international standard is in doubt. Here, the authors propose a statistical model that correlates dark current and photo-current, show how it can be used to determine detection limit.

    • Lei Pan
    • , Shreetu Shrestha
    •  & Lei R. Cao
  • Article
    | Open Access

    Artificial sodium channels open up the way to new separation technologies but remains highly challenging. In this work, the authors report an artificial sodium-selective ionic device, built on porous crown-ether crystals with a sodium ion selectivity against calcium ions exceeding that one of biological ion channel counterparts.

    • Tingyan Ye
    • , Gaolei Hou
    •  & Jun Gao
  • Article
    | Open Access

    The superior density of passive analog memristive devices can potentially enable efficient implementation of very large scale neural networks; however, device to device variability is currently too large to take advantage of this. Here, Kim et al demonstrate an impressive reduction in this variability, with a large passive memristive array.

    • H. Kim
    • , M. R. Mahmoodi
    •  & D. B. Strukov
  • Article
    | Open Access

    Uninterrupted monitoring of pressure and temperature at skin interfaces can help to minimize the potential for pressure injuries in hospitalized or bedridden patients. Here, the authors introduce a soft, skin-mountable sensor that can continuously provide readings via antennas mounted under bedding, and demonstrate the functionality and robustness of the devices on patients.

    • Yong Suk Oh
    • , Jae-Hwan Kim
    •  & John A. Rogers
  • Article
    | Open Access

    Additives have been widely used for passivating defects in perovskite semiconductors, yet the role of additive and their interaction is not clear. Here, the authors reveal an additive-assisted crystal formation in FAPbI3 perovskite by tracking the chemical interaction in the precursor solution and crystallographic evolution using multi-functional additives.

    • Lin Zhu
    • , Hui Cao
    •  & Jianpu Wang
  • Article
    | Open Access

    The miniaturization of biocompatible microsystems that enable self-sufficiency and autarkic operations is ever increasing. Here, the authors demonstrate a robust integratable nano-biosupercapacitor with enhanced performance in complex biological fluids, thus enabling autarkic sensor operation in blood.

    • Yeji Lee
    • , Vineeth Kumar Bandari
    •  & Oliver G. Schmidt
  • Article
    | Open Access

    Unrestricted integration of single-crystal oxide films on Si substrates allows for exploitation of emerging functionality of new materials in mature silicon devices. Here the authors integrate epitaxial oxide films with sharp metal-insulator transition on Si substrates by epitaxial lift-off of a freestanding nanomembrane.

    • Dong Kyu Lee
    • , Yunkyu Park
    •  & Junwoo Son
  • Article
    | Open Access

    Tailoring the crystallization kinetics of materials is important for targeting applications. Here the authors observe a remarkable dependence of crystallization and vitrification kinetics and attribute it to systematic bonding changes for a class of materials between metallic and covalent bonding.

    • Christoph Persch
    • , Maximilian J. Müller
    •  & Matthias Wuttig
  • Article
    | Open Access

    Two-dimensional hybrid perovskites exhibiting Rashba/Dresselhaus spin-splitting can be potentially used for spin-selective transport and spin-orbitronics, yet the structural determinants of spin-splitting are not well-understood. Here, the authors reveal a specific inorganic layer distortion that correlates with bulk spin-splitting in these materials.

    • Manoj K. Jana
    • , Ruyi Song
    •  & David B. Mitzi
  • Article
    | Open Access

    Though shape-changing devices are promising for future haptic displays, existing designs fail to provide smooth surfaces for the user during tactile exploration. Here, the authors utilize flexible auxetic structures to realize shape displays with smooth surfaces and different Gaussian curvatures.

    • Binghao Wang
    • , Wei Huang
    •  & Antonio Facchetti
  • Article
    | Open Access

    Wearable polymer ultraviolet (UV) detectors seriously suffer from slow response time. Here, the authors propose a UV illuminance-mechanical stress-electric signal conversion based on well-defined ionic liquid-containing liquid crystalline polymer and highly elastic polyurethane composite fabrics, to achieve a robust UV monitoring and shielding device with a fast response time of 5 s.

    • Xiaoxiong Zheng
    • , Yining Jia
    •  & Aihua Chen
  • Article
    | Open Access

    Pulsed operation of perovskite light-emitting diodes is of particular importance in display and visible light communication, yet the ionic behaviour under this mode is not well-understood. Here, the authors reveal that the transient electroluminescence intensity increases with increasing pulse width as the result of accumulation of mobile ions at the interfaces.

    • Naresh Kumar Kumawat
    • , Wolfgang Tress
    •  & Feng Gao
  • Article
    | Open Access

    The typical approach to electronics is to integrate sensors, power units, and controlling components on a printed circuit board (PCB). Here, the authors demonstrate a self-powered and fully integrated combination of sensors and controlling components that is woven, rather than integrated onto a PCB, allowing for wearable health monitoring.”

    • Yuxin Yang
    • , Xiaofei Wei
    •  & Xing Fan
  • Article
    | Open Access

    Thermally activated delayed fluorescence organic light-emitting diodes (TADF-OLEDs) rely on high triplet energy interlayers to confine excitons, which results in reduced performance. Here, the authors report high-performance blue TADF-OLEDs with below bandgap electroluminescence.

    • Maria Vasilopoulou
    • , Abd. Rashid bin Mohd Yusoff
    •  & Nicola Gasparini
  • Article
    | Open Access

    Though bound states in the continuum (BICs) in acoustic systems are attractive for acoustic resonators design, acoustic BICs typically show low Q-factor. Here, the authors report a high performance open acoustic resonator that supports symmetry-protected, Friedrich-Wintgen and mirror symmetry-induced BICs.

    • Lujun Huang
    • , Yan Kei Chiang
    •  & Andrey E. Miroshnichenko
  • Article
    | Open Access

    A good way to identify microscopic conduction regimes where current flow deviates from Ohm’s law is still lacking. Here, the authors identify Sondheimer oscillations as a quantitative probe of the length scale of relaxing electron scattering in studying the non-ohmic electron flow of WP2 crystals.

    • Maarten R. van Delft
    • , Yaxian Wang
    •  & Philip J. W. Moll
  • Article
    | Open Access

    Realizing an artificial camouflage device with a high spatial resolution by adapting to the surrounding environment in real-time is a challenging task, mainly associated with device fabrication and integration with sensor and control circuits. To overcome these limitations, the authors utilize thermochromic liquid crystal ink that reacts to the feedback control system of the vertically stacked silver nanowire heater.

    • Hyeonseok Kim
    • , Joonhwa Choi
    •  & Seung Hwan Ko
  • Article
    | Open Access

    Graded bulk-heterojunction organic solar cell with well-defined vertical phase separation has the potential to surpass the classical counterpart, thus the optimisation of this structure is crucial. Here, the authors reveal solvent selection strategies for optimising morphology of the structure, enabling efficient, eco-friendly, and scalable solar cells.

    • Ying Zhang
    • , Kuan Liu
    •  & Gang Li
  • Article
    | Open Access

    Multidentate molecular additives are widely used to passivate perovskite, yet the role of chelate effect is still unclear. Here, the authors investigate a wide range of additives with different coordination number and functional moieties to establish correlation between coordination affinity and perovskite crystallisation dynamics.

    • Yatao Zou
    • , Pengpeng Teng
    •  & Feng Gao
  • Article
    | Open Access

    Though shape-changing devices are promising for future haptic displays, existing designs fail to provide smooth surfaces for the user during tactile exploration. Here, the authors utilize flexible auxetic structures to realize shape displays with smooth surfaces and different Gaussian curvatures.

    • Anthony Steed
    • , Eyal Ofek
    •  & Mar Gonzalez-Franco
  • Article
    | Open Access

    An avalanche photodiode is an opto-electronic amplifier that uses impact ionization to provide enhanced sensitivity at the expense of excess noise. In this manuscript, the authors demonstrate that a small amount of Bismuth (Bi) in Gallium Arsenide (GaAs) avalanche photodiodes significantly reduces this excess noise.

    • Yuchen Liu
    • , Xin Yi
    •  & John P. R. David
  • Article
    | Open Access

    Sensing mechanical signals is an important aspect for a range of applications of E-skins. Here, the authors report on the creation of deforming iontronic sensing structures which can use ionic transport through tissues to create a simple and sensitive E-skin for sensing touch, pulse and motion demonstrating application.

    • Pang Zhu
    • , Huifeng Du
    •  & Chuan Fei Guo
  • Article
    | Open Access

    Ferroelectric liquid crystals (FLCs) have faster optical response times than nematic crystals, but they are also less robust to external shock. Here the authors develop an FLC geometry that reduces the sensitivity to external disruption through self-healing, making them more stable for applications.

    • Peter J. M. Wyatt
    • , James Bailey
    •  & J. Cliff Jones
  • Article
    | Open Access

    Maragoni microswimmers show the advantage of self-propulsion but their development is limited by fabrication techniques. Here, the authors use a photopatterning method which allows for a high throughput production of maragoni microswimmers with multiple functional parts and distinct materials properties.

    • Yeongjae Choi
    • , Cheolheon Park
    •  & Wook Park
  • Article
    | Open Access

    Appropriate triboelectric material selection is vital to for high performance direct current triboelectric nanogenerator (DC-TENG). The authors here provide effective selection rules as guideline to select triboelectric materials for DC-TENG to reduce the trial-and-error cost for DC-TENG’s research.

    • Zhihao Zhao
    • , Linglin Zhou
    •  & Zhong Lin Wang
  • Article
    | Open Access

    Despite advances on fabrication of stretchable interconnects, realizing functional electronics with integrated solid-state technology (SST) remains a challenge. Here, the authors report a reversible Pol-Gel transition method for fabrication of liquid-metal based, chip-integrated, printed stretchable circuits.

    • Pedro Alhais Lopes
    • , Bruno C. Santos
    •  & Mahmoud Tavakoli
  • Article
    | Open Access

    The majority of polar structures emerging naturally in ferroelectrics are topologically trivial. Here, the authors demonstrate reconstruction of topologically trivial strip-like domain architecture into arrays of polar vortex in (PbTiO3)10/(SrTiO3)10 superlattice.

    • Congbing Tan
    • , Yongqi Dong
    •  & Jiangyu Li
  • Article
    | Open Access

    Dielectric elastomer actuators (DEAs) with large electrically actuated strain can be used in non-magnetic motors, but high stiffness, poor strength and slow response currently limit the application of DEAs. Here, the authors optimize the crosslinking network in a polyacrylate elastomer to enable a DEA with high toughness and actuation strain and use the polyacrylate to build a motor which can be driven under low electric field.

    • Li-Juan Yin
    • , Yu Zhao
    •  & Zhi-Min Dang
  • Article
    | Open Access

    For printed electronics to realize its potential as a sustainable ubiquitous technology, eco-friendly solvents that deliver excellent ink performance must be found. Here, the authors report a free online tool that identifies functional green solvents for solution-processed printed electronics.

    • Christian Larsen
    • , Petter Lundberg
    •  & Ludvig Edman
  • Article
    | Open Access

    Electric field induced ion migration is a well-known phenomenon in perovskite, but the consequences are notorious, and thus needs to be prevented. Here, on the other hand, the authors cleverly manipulate this event for realising resistive random-access memory and light-emitting electrochemical cell in one device based on CsPbBr3 quantum dots.

    • Meng-Cheng Yen
    • , Chia-Jung Lee
    •  & Ya-Ju Lee
  • Article
    | Open Access

    Surface of colloidal quantum dot is sensitive to water, and the interaction could potentially alter its chemical environments. Here, Shi et al. investigate how the interaction effects the nanostructures and carrier dynamic in CQDs, and subsequently introduce meniscus-guided coating technique to mitigate CQD fusion triggered by water adsorption.

    • Guozheng Shi
    • , Haibin Wang
    •  & Wanli Ma
  • Article
    | Open Access

    The immobilization of catalysts within the pores of conductive metal-organic frameworks (C-MOFs) via facile and scalable methodologies remains challenging. Here the authors report a microfluidic channel-embedded solution shearing process that enables the high throughput, large-area, single-step preparation of Pt nanocatalyst-embedded C-MOF thin films.

    • Jin-Oh Kim
    • , Won-Tae Koo
    •  & Steve Park
  • Article
    | Open Access

    Control of the phases associated with the metal-insulator transition in VO2 underpins its applications as a phase change material. Here, the authors report phase management by means of oxide inhibitor-assisted growth and present high-performance VO2 actuators based on asymmetric phase transition routes.

    • Run Shi
    • , Yong Chen
    •  & Chun Cheng
  • Article
    | Open Access

    Force sensing using mechanochromic polymers is currently limited to two state systems and does not allow directly correlating the force with the absorption or emission wavelength. Here, the authors present a mechanochromic donor-acceptor torsional spring that undergoes force-induced planarization during uniaxial elongation leading to force dependent red-shifted absorption and emission spectra.

    • Maximilian Raisch
    • , Wafa Maftuhin
    •  & Michael Sommer
  • Article
    | Open Access

    In this manuscript, the authors grow very thin layers of FeAs in a matrix of InAs. The resulting superlattice displays ferromagnetism, with the Curie temperature varying depending on the layer thickness. These results further illustrate the wide array of intriguing ground states of materials with tetrahedral FeAs bonds

    • Le Duc Anh
    • , Taiki Hayakawa
    •  & Masaaki Tanaka
  • Article
    | Open Access

    Despite the impressive demonstrations with silicon and oxide memristors, realizing efficient roots of trust for resource-constrained hardware remains a challenge. Here, the authors exploit switching behavior in one dimensional perovskite memristors to design security primitives for key generation and device authentication.

    • Rohit Abraham John
    • , Nimesh Shah
    •  & Nripan Mathews
  • Article
    | Open Access

    Realizing efficient white organic light-emitting diodes (WOLEDs) with a single thermally-activated delayed fluorescence (TADF) emissive layer remains a challenge. Here, the authors design energy-relaying exciplex hosts with multi-triplet excited states for efficient single-emissive-layer TADF WOLEDs.

    • Chunmiao Han
    • , Ruiming Du
    •  & Wei Huang