Techniques and instrumentation

  • Article
    | Open Access

    Bioinspired materials require an understanding of how biomaterials achieve the materials properties. Here, the authors report on the load-bearing shell of Discinisca tenuis and explore how hydration changes the dry shell from hard and stiff to soft and flexible within minutes by reorganisation caused by organic matrix swelling.

    • Johannes Ihli
    • , Anna S. Schenk
    •  & Fabio Nudelman
  • Article
    | Open Access

    Free carriers and electrical polarization coexist in ferroelectric metals. Here, the authors use a capacitive method to probe the electronic compressibility of free carriers in a tunable semimetal, extract the polarized contribution, and study the carrier dependence of the ferroelectric state.

    • Sergio C. de la Barrera
    • , Qingrui Cao
    •  & Benjamin M. Hunt
  • 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

    In chocolate production, a complicated tempering process is used to guide the crystallization of cocoa butter towards its most desirable polymorph, which gives the chocolate proper melting behavior, gloss, and snap—hallmarks of good quality chocolate. Here, the authors find that simply adding a specific phospholipid also directs crystallization towards this polymorph, producing chocolate with comparable microstructure and properties to tempered chocolate.

    • Jay Chen
    • , Saeed M. Ghazani
    •  & Alejandro G. Marangoni
  • Article
    | Open Access

    The limited strength of green parts have been a major hurdle in the Binder Jet Additive Manufacturing. Here the authors apply polyethyleneimine binder to print silica sand structures with double the flexural strength of green parts and 8-fold increase in the strength upon reactive infiltration.

    • Dustin B. Gilmer
    • , Lu Han
    •  & Tomonori Saito
  • Article
    | Open Access

    Electron beam lithography (EBL) is renowned to provide fabrication resolution in the deep nanometer scale but their incapability of arbitrary 3D nanofabrication poses a major limitation to the technique. Here, the authors demonstrate a manufacturing technique of functional 3d nanostructures at a resolution of sub-15 nm using voltage-regulated 3d EBL.

    • Nan Qin
    • , Zhi-Gang Qian
    •  & Tiger H. Tao
  • Article
    | Open Access

    Balances for nanoparticles such as resonating fluid-filled cantilevers usually probe only mass through changes in oscillation frequency. Katsikis and Collis et al. tap information from previously ignored rotational motion to simultaneously measure particle mass and volume.

    • Georgios Katsikis
    • , Jesse F. Collis
    •  & Scott R. Manalis
  • Article
    | Open Access

    The morphology of semicrystalline plastics on the 1-100 μm scale, such as spherulites, strongly affect mechanical and other properties of the material but currently only 2D imaging techniques are available. Here, the authors use fluorescence labels and confocal microscopy to visualize the internal structure of neat polymers and composites in 3D and reveal unsuspected morphologies.

    • Shu-Gui Yang
    • , Zhen-Zhen Wei
    •  & Goran Ungar
  • Article
    | Open Access

    The authors introduce an analytical approach for quantitative analysis of 3D atom dynamics during electron microscopy. They image a Co-Mo-S nanocrystal with 1.5 Å resolution, and observe chemical transformations caused by beam-stimulated vibrations.

    • Fu-Rong Chen
    • , Dirk Van Dyck
    •  & Stig Helveg
  • Article
    | Open Access

    Spatiotemporal dynamic of charge carriers is commonly studied with optical or photoconductivity measurements, yet these techniques come with their own limitations. To circumvent these limits, the authors probe the free-carrier diffusion dynamics of microsecond lifetimes via laser-illuminated microwave impedance microscopy.

    • Xuejian Ma
    • , Fei Zhang
    •  & Keji Lai
  • Article
    | Open Access

    Advanced fabrication techniques enable a wide range of quantum devices, such as the realization of a topological qubit. Here, the authors introduce an on-chip fabrication technique based on shadow walls to implement topological qubits in an InSb nanowire without fabrication steps such as lithography and etching.

    • Sebastian Heedt
    • , Marina Quintero-Pérez
    •  & Leo P. Kouwenhoven
  • 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

    The authors demonstrate efficient excitation of nanodiamonds by a focused beam of helium ions, resulting in ionoluminescence. They use this for quantification and correlative localization of single particles within a whole cell at sub-30 nm resolution, and investigate nanodiamond radiosensitisation effects.

    • Zhaohong Mi
    • , Ce-Belle Chen
    •  & Andrew A. Bettiol
  • Article
    | Open Access

    Honeycomb layered oxides are an emerging class of materials with peculiar physicochemical properties. Here, the authors report the synthesis and electrochemical energy storage characterisations of a mixed-alkali honeycomb layered oxide material capable of storing Na and K ions simultaneously.

    • Titus Masese
    • , Yoshinobu Miyazaki
    •  & Tomohiro Saito
  • Article
    | Open Access

    The detailed understanding of the structural variations during cycling in cathodes for Zn-ion aqueous rechargeable batteries is still limited. Here, the authors utilize atomic-column-resolved scanning transmission electron microscopy to elucidate multiphase evolution during hydrated Zn-Ion insertion in vanadium oxide.

    • Pilgyu Byeon
    • , Youngjae Hong
    •  & Sung-Yoon Chung
  • Article
    | Open Access

    Photon upconversion with near-infrared excitation and ultraviolet emission has many applications, but suffers from low quantum efficiency. Here, the authors report a six-photon upconversion process in nanoparticles with heterogeneous core-multishell structure, that regulate the energy transfer pathway.

    • Qianqian Su
    • , Han-Lin Wei
    •  & Dayong Jin
  • Article
    | Open Access

    Structural and morphological control of crystalline nanoparticles is crucial in heterogeneous catalysis. Applying DFT-assisted solid-state NMR spectroscopy, we determine the surface crystal and electronic structure of Ni2P nanoparticles, unveiling NMR nanocrystallography as an emerging tool in facet-engineered nanocatalysts.

    • Wassilios Papawassiliou
    • , José P. Carvalho
    •  & Andrew J. Pell
  • Article
    | Open Access

    Despite the important role of ligands in designing nanoparticles, directly imaging them on the nanoparticle surface remains a challenge. Here, the authors use atom probe tomography to map the spatial distribution of ligands on nanoparticles and reveal that the interplay between halide and cetrimonium ligands decides the oxidation resistance and shape of Pd nanoparticles.

    • Kyuseon Jang
    • , Se-Ho Kim
    •  & Pyuck-Pa Choi
  • Article
    | Open Access

    Adsorption is a fundamentally important process but challenging to quantify, especially at the nanoscale. Here, the authors map the adsorption affinity and cooperativity of various ligands on single gold nanoparticles and discover adsorption crossover behaviors between different facets, leading to a strategy to control particle shape.

    • Rong Ye
    • , Ming Zhao
    •  & Peng Chen
  • 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

    The construction of Z-scheme heterostructures is of great significance for realizing efficient photocatalytic water splitting. Here, the authors report an interfacial chemical bond and internal electric field modulated Z-Scheme Sv-ZnIn2S4/MoSe2 photocatalyst for efficient hydrogen evolution.

    • Xuehua Wang
    • , Xianghu Wang
    •  & Zhenjiang Li
  • Article
    | Open Access

    Nuclear spin polarization and relaxation can be studied using nuclear magnetic resonance (NMR). Here the authors demonstrate a combination of fast-field cycling and optical magnetometry techniques, to realize a NMR sensor that operates in the region of very low frequency and high relaxation rate.

    • Sven Bodenstedt
    • , Morgan W. Mitchell
    •  & Michael C. D. Tayler
  • Article
    | Open Access

    The authors present a microwave imaging system that can operate in continuous transmit-receive mode. Using an array of transmitters, a single receiver and a reconstruction matrix that correlate random time patterns with the captured signal, they demonstrate real-time imaging and tracking through a wall.

    • Fabio C. S. da Silva
    • , Anthony B. Kos
    •  & Archita Hati
  • Article
    | Open Access

    3D real-space analysis of thick nanoparticle crystals is non-trivial. Here, the authors demonstrate the structural analysis of a bulk-like Laves phase by imaging an off-stoichiometric binary mixture of hard-sphere-like nanoparticles in spherical confinement by electron tomography, enabling defect analysis on the single-particle level.

    • Da Wang
    • , Ernest B. van der Wee
    •  & Alfons van Blaaderen
  • Article
    | Open Access

    Charge ordering and superconductivity are known to compete in layered cuprates; however, precise real-space characterization of their interplay has been lacking. Here, the authors address this using atomically-resolved cross-sectional scanning tunnelling microscopy and spectroscopy on cryogenically cleaved YBa2Cu3O6.81.

    • Chun-Chih Hsu
    • , Bo-Chao Huang
    •  & Ya-Ping Chiu
  • Article
    | Open Access

    Quantification of Li ions in local area is key to understand the degradation of Li ion batteries. Here the authors report Li compositional gradient evolution in the cathode after charge-discharge cycles using a complementary study via atom probe tomography and scanning transmission electron microscopy.

    • Byeong-Gyu Chae
    • , Seong Yong Park
    •  & Woo Sung Jeon
  • Article
    | Open Access

    Upscale fabrication of functionalized microparticles is a pending challenge. Here, Kim et al. exploit the rheology of a thixotropic medium to grind sizeable amounts of raw material into well-defined colloidal dispersions, physically stabilized for further production steps.

    • Sang Yup Kim
    • , Shanliangzi Liu
    •  & Rebecca Kramer-Bottiglio
  • Article
    | Open Access

    Particle fusion can improve signal-to-noise ratio in single molecule localization microscopy, but is limited by structural heterogeneity. Here, the authors demonstrate an unsupervised classification method that differentiates structurally different DNA origami structures without prior knowledge.

    • Teun A.P.M. Huijben
    • , Hamidreza Heydarian
    •  & Bernd Rieger
  • Article
    | Open Access

    Imaging through scattering media is possible using a transmission matrix or the memory effect. Here, the authors describe the nature of optical memory effects in structures of arbitrary geometry and use this framework to estimate the transmission matrix of an optical fibre from just one end.

    • Shuhui Li
    • , Simon A. R. Horsley
    •  & David B. Phillips
  • Article
    | Open Access

    Studying the development of silk structure is important for understanding material properties and biomimetics. Here, the authors use ex vivo processing to characterise the stages of silk spinning and identify a consolidation phase where transient water pockets emerge due to multiple factors leading to nanofibril coalescence.

    • Quan Wan
    • , Mei Yang
    •  & Mingying Yang
  • Article
    | Open Access

    Assessing mechanics of nanoporous silicon is challenging, but important for new applications. Here, the authors use non-destructive laser-excited elastic guided waves detected contactless, to study dry and liquid-infused single-crystalline porous silicon, revealing its complex mechanics and significant deviations from bulk silicon.

    • Marc Thelen
    • , Nicolas Bochud
    •  & Patrick Huber
  • Article
    | Open Access

    Studying dynamic processes in mechanobiology has been challenging due to lack of appropriate tools. Here, the authors present an interference-based method, illuminated via two rapidly alternating wavelengths, which enables real-time mapping of nanoscale forces with sub-second mechanical fluctuations.

    • Andrew T. Meek
    • , Nils M. Kronenberg
    •  & Malte C. Gather
  • Article
    | Open Access

    Antiferromagnets (AFM) exhibit faster magnetization dynamics, and have immunity to stray fields, making AFMs attractive for spintronic devices. Here, the authors investigate the behaviour of domain walls in AFMs, and find a new type domain wall, a superposition of two adjacent rotational domains.

    • Jonas Spethmann
    • , Martin Grünebohm
    •  & André Kubetzka
  • Article
    | Open Access

    Tip-enhanced nano-spectroscopy suffers from inconsistent signal and difficulty in polarization-resolved measurement. Here, the authors present adaptive tip-enhanced nano-spectroscopy, which enables the additional signal enhancement and near-field polarization control via dynamic wavefront shaping.

    • Dong Yun Lee
    • , Chulho Park
    •  & Kyoung-Duck Park
  • Article
    | Open Access

    Nanopores have been used for direct observation of RNA structure in native environments but have limited RNA differentiation capabilities. Here, the authors report on the use of Mycobacterium smegmatis porin A nanopores for the trapping and translocation identification of microRNA, siRNA, tRNA and ribosomal RNA.

    • Yuqin Wang
    • , Xiaoyu Guan
    •  & Shuo Huang
  • Article
    | Open Access

    Implementation of digital electronics into fibres can enable real time monitoring of human physiological functions. Loke et al. show how digital functionalities can be incorporated into thin flexible polymeric fibre strands and applied for on-body machine-learning and intelligent textiles.

    • Gabriel Loke
    • , Tural Khudiyev
    •  & Yoel Fink
  • Article
    | Open Access

    Creating predictable, controllable nanoparticles relies on a mechanistic understanding of their synthesis. Here, through integrated in situ liquid microscopy and first-principles calculations, the authors elucidate the atomistic details involved in the formation of colloidal core-shell nanoparticles.

    • Wenpei Gao
    • , Ahmed O. Elnabawy
    •  & Miaofang Chi
  • Article
    | Open Access

    In-situ methods are important for investigating the local structure and function in molecular nanostructures but such investigations often involve laborious labeling methods that can disrupt behavior or are not fast enough to capture stimuli-responsive phenomena. Here, the authors use X-rays resonant with molecular bonds to demonstrate an in-situ nanoprobe that eliminates the need for labels and enables data collection times within seconds.

    • Terry McAfee
    • , Thomas Ferron
    •  & Brian A. Collins