Understanding the reactivity of nitrogen oxides (NO x ) at interfaces remains a challenge for environmental monitoring and air quality control. Here, we show that 4-cyano-4'-pentylbiphenyl (5CB) liquid crystals (LCs) supported on coinage metal Au, Ag, and Cu surfaces exhibit NO2-induced orientational changes that provide an optical probe of NO2 adsorption and interfacial interactions on metal surfaces at parts-per-million (ppm) concentrations. Films of Au were prepared by electron-beam deposition and subsequently coated with submonolayer to multilayer films of Ag or Cu via electrochemical deposition. X-ray photoelectron spectroscopy reveals that these Ag and Cu films oxidize under ambient conditions to form oxygen-decorated Ag and Cu2O surface oxides, respectively. By combining polarized light microscopy, polarization-modulation infrared reflection-absorption spectroscopy (PM-IRRAS), and density functional theory (DFT) calculations, we show that 5CB adopts a planar orientation on Au and Cu overlayers on Au (Cu/Au) surfaces, but a perpendicular alignment on Ag overlayers on Au (Ag/Au). Upon exposure to 10 ppm of NO2 balanced in N2 at ambient pressure and temperature, 5CB undergoes substrate-dependent orientational transitions. On Au, a reversible planar-to-perpendicular transition is observed, which DFT calculations attribute to electrostatic stabilization of the perpendicular binding mode of 5CB by adsorbed NO2. On Cu/Au, the same transition in orientation of the LC occurs, but it is irreversible and correlates with the oxidation of Cu2O to CuO by NO2. Over ambient-exposed Ag/Au films, however, 5CB is unresponsive to NO2, retaining a perpendicular alignment before and after exposure. DFT calculations indicate that the presence of the LC modifies surface reaction thermodynamics on Ag/Au, shifting the preferred NO x species formed from N2O4 in the absence of LCs to NO2 in their presence, and that NO2 adsorption does not alter the preferred orientation of 5CB. Taken together, these results demonstrate how substrate-dependent surface composition and oxidation state govern NO2 adsorption and speciation on coinage metal surfaces with and without LC overlayers.

The chemically responsive properties of surface-anchored isothiocyanate-terminated (-NCS) liquid crystal compounds (LCs) have not been investigated before. Therefore, a novel series of terminal alkoxy and fluoroalkoxy tail isothiocyanate liquid crystal compounds was developed that exhibit nematic liquid crystal phase properties near ambient temperature. In order to achieve a low-melting liquid crystal compound, another series of alkoxy isothiocyanate terminal liquid crystal compounds with lateral fluorine substitution was synthesised and analysed. These lateral fluorine-substituted alkoxy isothiocyanate compounds not only lower the melting point but also show improved mesogenic behaviour compared to their non-fluorinated alkoxy isothiocyanate analogues. To investigate their potential application as chemoresponsive sensor materials, the surface anchoring behaviour of NCS-terminated LCs was investigated on metal-salt-decorated surfaces using density functional theory (DFT) calculations and experimental studies. DFT-based analysis, combined with experimental observations, revealed that mesogens bearing an isothiocyanate (-NCS) terminal group exhibit surface interactions that differ from those of mesogens with a nitrile (-CN) terminal group. We use these surface interactions to demonstrate the design of an NCS-terminated LC that responds to ozone gas.

Liquid-liquid phase separation (LLPS) and other forms of condensed phase formation play important roles in many cellular processes. Elucidating the noncovalent interaction networks that underlie condensate formation is a fundamental challenge. Cation-π interactions between Arg and Tyr side chains have been proposed as a driving force for many forms of protein-mediated condensate formation. Efforts to probe this hypothesis with ribosomally generated proteins are constrained by limits on residue incorporation. To transcend these limits, we developed a two-component system comprising a long Arg-rich protein fragment, generated via heterologous expression, and a short anionic Tyr-rich peptide, generated via chemical synthesis. Phase separation occurred when these components were mixed at low concentrations (5 μM each). Global replacements of Tyr with noncanonical residues were conducted to interrogate side chain contributions to condensate formation. The results suggest that cation-π interactions are not essential for phase separation in our system, and that even when cation-π interactions contribute, their role may not be dominant. H-bond donor properties of the Tyr side chain hydroxyl appear to play a significant role, along with Coulombic forces, in driving condensate formation mediated by the anionic Tyr-rich peptide and the Arg-rich protein fragment.

Solid-binding peptides (SBPs) are versatile molecules that can control a range of atomic-scale interfacial processes, but they remain challenging to discover. Current approaches for discovery rely on directed evolution, which samples only a small fraction of possible sequences. Data-driven methods for therapeutic peptides are also not applicable as they rely on crystal structures whereas peptides adopt varied conformations at solid surfaces. To address this challenge, we recently combined biophysical modeling and machine learning to design plastic-binding peptides that were predicted to have strong adsorption enthalpies. Here, we evaluate these designs using steered molecular dynamics and single-molecule force measurements and identify de novo designed peptides that bind strongly to polyethylene. Experimental adhesion forces exceed those previously reported for SBPs, and adsorption free energies from metadynamics simulations support strong binding. Analysis of the designed peptides reveals blocks of non-polar and charged residues, which enables them to adopt conformations that segregate non-polar amino acids to the plastic surfaces (generating hydrophobic interactions) and charged amino acids away from the surfaces. The contact patterns within the non-polar blocks depend on sequence context and polyolefin type. Overall, we validate a general approach for de novo SBP discovery that has broad scientific and engineering applications.

Biological cells are often damaged by interactions with fluid interfaces, yet the cell-scale processes that underlie their destruction have not been fully elucidated. Here we investigate whether interactions of cells at aqueous interfaces of thermotropic liquid crystals (LCs) drive changes in LC ordering, thereby generating spatiotemporal optical signatures that yield insights into the pathways by which single cells are damaged at fluid interfaces and how molecular adsorbates influence those pathways. MCF10A breast epithelial cells were sedimented onto micrometer-thick films of nematic LCs and imaged using optical microscopy. We found that the cells exhibited a lag phase on the interface (lasting seconds to an hour during which no optical response of the LC was evident) that was followed by rapid lateral displacement of the cells and the generation of complex spatiotemporal patterns in the LC. Fingering instabilities evident in the patterned optical response revealed deconstruction of cells and redistribution of cellular components driven by interfacial tension gradients. Pretreatment of the LC interface with amphiphilic adsorbates altered spreading dynamics and domain shapes, suggesting a role for Marangoni stresses in the disassembly pathway and revealing angular spatial patterns consistent with a crossover to capillary fracturing driven by interfacial elasticity. Fluorescence imaging along with control experiments with synthetic vesicles and red blood cells enabled spatiotemporal features of the LC response to epithelial cells to be associated with specific intracellular structures (nucleus, plasma membrane, and cytosol). The duration of the lag phase was also found to be influenced by cell-surface expression levels of the mucin MUC1. Overall, our findings reveal key physical processes that occur when cells interact with fluid interfaces and highlight the potential of LC interfaces to form the basis of single cell-level analyses of biophysical properties.

Many of the physical properties of liquid crystals can be tailored and enhanced by the well- established process of selective fluorination. Amongst the best-known and studied thermotropic liquid crystals are the cyanobiphenyls, which have proven to be an excellent platform for evaluating structural changes that may later be applied to other liquid crystal classes. In this study, building on our previous research, fluorination was carried out at the individual tail sites of alkylcyanobiphenyl using methods including bimolecular nucleophilic substitution reaction (SN2), epoxidation, regioselective epoxide opening, Suzuki reaction, nucleophilic addition reaction, and deoxyfluorination chemistry. All the compounds with fluorination at the individual tail sites of alkylcyanobiphenyl remained mesogenic, with a monotropic nematic phase that supercooled at or below room temperature. Binary mixtures were prepared from these compounds that helped prevent recrystallisation. Additionally, the enantiomers of 4-cyano-4'-pentylbiphenyl (5CB) with fluorination at position three of the tail were synthesised, which were found to have a cholesteric mesophase at room temperature. Chiral high-performance liquid chromatography (HPLC) confirmed the high enantiomeric purity of these compounds. The phase behaviour of the hydroxy intermediates was also explored and is reported in this article. The dipole moments of these synthesised fluorinated alkylcyanobiphenyls were also evaluated and are presented.

Recent studies have reported that the overexpression of MUC1 glycoproteins on cell surfaces changes the morphology of cell plasma membranes and increases the blebbing of vesicles from them, supporting the hypothesis that entropic forces exerted by MUC1 change the spontaneous curvature of cell membranes. However, how MUC1 is incorporated into and influences the size and biophysical properties of plasma-membrane-blebbed vesicles is not understood. Here we report single-vesicle-level characterization of giant plasma membrane vesicles (GPMVs) derived from cells overexpressing MUC1, revealing a 40x variation in MUC1 density between GPMVs from a single preparation and a strong correlation between GPMV size and MUC1 density. By dispersing GPMVs in aqueous liquid crystals (LCs), we show that the elasticity of the LC can be used to strain individual GPMVs into spindle-like shapes, consistent with the straining of fluid-like membranes. To quantify the influence of MUC1 on membrane mechanical properties, we analyze the shapes of strained GPMVs within a theoretical framework that integrates the effects of MUC1 density and GPMV size on strain. We measure the spontaneous curvature of GPMV membranes to be 2-10 mu m-1 and weakly influenced by the 40x variation in MUC1 density, a conclusion we validate by performing independent experiments in which MUC1 is enzymatically removed from GPMVs. Overall, our study advances the understanding of heterogeneity in size and MUC1 density in GPMVs, and establishes single-vesicle-level methods for characterization of mechanical properties within a heterogeneous population of GPMVs. Furthermore, our measurements highlight differences between membrane properties of GPMVs and their parent cells.

Reflection and refraction are ubiquitous phenomena with extensive applications, yet minimizing energy loss and information distortion during these processes remains a significant challenge. This study examines the behavior of structurally stable solitons, known as directrons, in nematic liquid crystals interacting with an interface where the director field orientation changes, despite identical physical properties, external potentials, and boundary anchoring in the two regions. During reflection and refraction, the directrons maintain nearly constant structure and velocity, ensuring energy conservation and information integrity. Microscopic analyses of the director field and macroscopic evaluations of effective potential are employed to elucidate the dependence of reflection and refraction probabilities on the directron's incident angle and the orientation difference across the interface. The findings provide valuable insights into the dynamics of solitary waves in structured liquid crystal systems, offering significant implications for the development of tunable photonic devices, reconfigurable optical systems, and nanoscale material engineering.

Recent studies have revealed that metal adatom clusters exhibit distinct catalytic properties compared to conventionally modeled extended facets. Here, we used periodic density functional theory (DFT) to investigate differences in O2 activation between two-dimensional clusters of Pd atoms supported on Au(111) (adclusters) and embedded within Au(111). We analyzed the barriers for O2* dissociation and desorption on Pd clusters ranging in size from one to nine Pd atoms in a (4 x 4) surface unit cell. Our findings revealed that, while O2* dissociation barriers between adclusters and embedded clusters are similar, adclusters exhibit significantly higher desorption barriers than embedded clusters by between 0.3 and 0.7 eV. This suggests that Au surfaces with Pd adclusters have enhanced selectivities for O2* dissociation over desorption, which may yield faster rates for processes limited by O2 activation. Additionally, we evaluated the stability of Pd-Au surfaces under vacuum and in the presence of O2*, calculating the temperature required for Pd adatom formation from Pd atoms embedded in Au(111). Our predictions show that adatom formation is unlikely as the competing desorption or dissociation of O2* occurs at lower temperatures for all considered cluster sizes. These findings highlight the role of surface roughness in catalytic processes on Pd-Au bimetallic surfaces.

The surface-induced ordering of liquid crystals (LC) has been harnessed to detect a wide range of chemical and biological stimuli. In most sensor designs, the information-rich response of the LC is transduced from an analyte-triggered change in the out-of-plane orientation of the LC. Quantifying the out-of-plane LC orientation, however, is often complicated by simultaneous changes in the in-plane orientation of the LC when using polarized light for transduction. Here we introduce a sensing approach that combines a dichroic dye-doped LC (DDLC) with unpolarized light and a photodiode to achieve precise quantification of analyte-driven changes in the out-of-plane orientations of LCs. We benchmark the performance of the new methodology against polarizer-based approaches using a model amphiphilic analyte in aqueous solution and show that the DDLC provides a substantial reduction in the coefficient of variation (300% to less than 5%), an enhanced analytical sensitivity (0.16 to 3.73 μM-1), and an expanded dynamic range. In addition, when used to sense concentration gradients of analytes, the new approach distinguishes differences as small as 0.03 μM/μm over a dynamic range of 2 μM/μm, significantly outperforming conventional polarizer-based approaches that detect differences of 0.3 μM/μm over a dynamic range of 0.6 μM/μm. Overall, we conclude that the improved sensing performance and simpler implementation (no polarizers) of the DDLC approach, as compared to conventional LC sensors based on crossed-polars, will facilitate the deployment of LC sensors in diverse contexts, including the development of high-throughput screens for chemical formulations.

Liquids comprising two coexisting phases can form a range of stable and metastable states, including wetting films, droplets and threads1-3. Processes that permit rapid and reversible transformations between these morphologies, however, have been difficult to realize because physical properties required for rapid shape change (for example, low interfacial tension or viscosity) provide pathways for relaxation that result in short-lived states. Fully reversible formation of long-lived microdomain states would expand the palette of properties that can be accessed dynamically using biphasic liquids (for example, tunable optical metamaterials). Here we report the discovery of shape-shifting and bistable microdomains of a biphasic liquid system consisting of an isotropic oil and a liquid crystalline oil. The isotropic oil forms stable wetting films ('original' shape) between solid surfaces and an overlying liquid crystal phase, and, when exposed to a transient (<1 s) a.c. electric field at low frequency (10 Hz), transforms into long-lived (>24 h) spherical domains ('temporary' shape) stabilized by topological defects in the liquid crystal1,4,5. Subsequent application of an a.c. electric field of high frequency (1 kHz) triggers solitons to form in the liquid crystal6-8, creating kinetic pathways that lead to remarkably rapid (<3 s) coalescence of the dispersed spherical domains and recovery of the original shape (wetting film)1,8,9. We show rapid and reversible switching between distinct optical states of the biphasic system, with each state persisting without continuous application of the field, thus providing a combination of optical properties long sought in thin liquid films10-17. The fully reversible and long-lived emulsion formation reported here appears promising for materials synthesis, microchemical systems and tunable optical metamaterials (for example, to control visibility and transmittance of light through windows)17-21.

Thrombosis, or pathological blood clot formation, is a dangerous and potentially fatal event that is often associated with implanted medical devices. Thrombi are comprised of platelets, plasma proteins, red blood cells (RBCs) and other molecular and cellular components. Extensive research has been conducted on the dynamics of platelet aggregation and deposition; however, the process of RBC entrapment remains under-explored. In this study, we used a microfluidic device and fluorescence microscopy to concurrently image platelets and RBCs during thrombus formation under flow and biomaterial conditions representative of implanted devices. We designed and applied MATLAB algorithms to track thrombi as they grew over time and interrogated thrombus growth and RBC accumulation trends. To probe the contributions of the unique mechanical properties of RBCs, we characterized the influence of induced RBC stiffness on thrombus forming behavior via imaging. To study the binding effects of known RBC surface antigens, we visualized thrombus formation with inhibition of glycoprotein (GP) IIb/IIIa and integrin-associated protein (IAP) respectively. We found that the accumulation and clustering of RBCs within the thrombi exhibited an inverse relationship with stiffness. Fibrillar structures were also present in these thrombi. Stiff RBCs enhanced platelet aggregate growth in all directions. Inhibition of surface binding proteins GPIIb/IIIa and IAP decreased the stability of thrombi. The results show that RBC deformability impacts entrapment location, fibril growth and spatial distribution. In turn, RBC binding stabilizes and anchors aggregates to surfaces. These findings will inform improved device design and multi-phase models of thrombosis that incorporate RBCs. STATEMENT OF SIGNIFICANCE: Thrombosis, the pathological formation of blood clots, is linked to cardiovascular disease and implanted devices. This study explores the mechanisms by which red blood cells (RBCs) become trapped in clots and their impact on clot properties. Using a microfluidic model, we show that RBC stiffness affects their accumulation and distribution within thrombi, influencing thrombus structure and composition. We also find that RBC surface proteins, such as GPIIb/IIIa and integrin-associated protein, contribute to thrombus stability. These findings will enhance thrombosis models and inform research on the interaction between biomaterials, including blood-contacting devices, and biological systems at the cellular and molecular levels.

Here we address if it is possible to couple changes in liquid crystal (LC) ordering with photocatalytic processes occurring on surfaces to enable the design of photoresponsive materials. We report that ultraviolet (UV) illumination of anatase (101) supporting 4 '-n-pentyl-4-biphenylcarbonitrile (5CB) leads to a change in LC ordering driven by photo-oxidation of 5CB to 4 '-cyano-4-biphenylcarboxylic acid (CBCA), as confirmed by infrared spectroscopy and mass spectrometry. Specifically, we find that a 0.09 monolayer (ML) surface coverage of the product CBCA on anatase (101) is sufficient to trigger the ordering transition of the LC from planar to homeotropic, thus reporting the transformation with high sensitivity. Additionally, we observe that the LC ordering serves as a reporter of the amount of adsorbed water on anatase (101), a key molecular species involved in the photocatalytic transformation of 5CB. We also demonstrate that the LC film alters the local concentration and structure of water adsorbed on titania, as characterized using infrared spectroscopy and electronic structure calculations. Lastly, the competitive adsorption of water and LC on anatase (101) is reported as a nonmonotonic trend in the rate of photocatalytic transformation of LC as a function of RH levels, a phenomenon captured by the rate of change of LC order. In summary, these results demonstrate that LCs couple to photocatalytic transformations on titania, offering designs of photoresponsive LCs, a novel readout of photocatalytic molecular events and the ability to tune interfacial photocatalytic processes.

Microtubules and catalytic motor proteins underlie the microscale actuation of living materials, and they have been used in reconstituted systems to harness chemical energy to drive new states of organization of soft matter (e.g., liquid crystals (LCs)). Such materials, however, are fragile and challenging to translate to technological contexts. Rapid (sub-second) and reversible changes in the orientations of LCs at room temperature using reactions between gaseous hydrogen and oxygen that are catalyzed by Pd/Au surfaces are reported. Surface chemical analysis and computational chemistry studies confirm that dissociative adsorption of H2 on the Pd/Au films reduces preadsorbed O and generates 1 ML of adsorbed H, driving nitrile-containing LCs from a perpendicular to a planar orientation. Subsequent exposure to O2 leads to oxidation of the adsorbed H, reformation of adsorbed O on the Pd/Au surface, and a return of the LC to its initial orientation. The roles of surface composition and reaction kinetics in determining the LC dynamics are described along with a proof-of-concept demonstration of microactuation of beads. These results provide fresh ideas for utilizing chemical energy and catalysis to reversibly actuate functional LCs on the microscale.

Over the past few decades, chemical vapor deposition (CVD) of [2.2]paracyclophanes has captured significant attention as an emergent technology, producing conformal, chemically pure, and pinhole-free coatings for biomedical and industrial applications. Compelling examples range from functional CVD polymers to tailored nanostructures. In this work, the unique functional properties of polymers derived from [2.2]paracyclophanes are connected with emergent applications. Special attention is given to the function-property relationships in the areas of electronic materials, biomaterials, and separation materials. A particular focus is to highlight the versatility of CVD polymerization to process these polymers. Chemical vapor deposition (CVD) is an effective technique to control the chemical, biological, and topographical properties of surfaces. In this perspective, CVD polymerization of [2.2]paracyclophanes is highlighted and emergent applications as electrical components, biological interfaces, and biomimetic nanostructures are discussed. image

Solitons in nematic liquid crystals facilitate the rapid transport and sensing in microfluidic systems. Little is known about the elementary conditions needed to create solitons in nematic materials. In this study, we apply a combination of theory, computational simulations, and experiments to examine the formation and propagation of solitary waves, or "solitons", in nematic liquid crystals under the influence of an alternating current (AC) electric field. We find that these solitary waves exhibit "butterfly"-like or "bullet"-like structures that travel in the direction perpendicular to the applied electric field. Such structures propagate over long distances without losing their initial shape. The theoretical framework adopted here helps identify several key factors leading to the formation of solitons in the absence of electrostatic interactions. These factors include surface irregularities, flexoelectric polarization, unequal elastic constants, and negative anisotropic dielectric permittivity. The results of simulations are shown to be in good agreement with our own experimental observations, serving to establish the validity of the theoretical concepts and ideas advanced in this work.

Liquid crystals (LCs), when interfaced with chemically functionalized surfaces, can amplify a range of chemical and physical transformations into optical outputs. While metal cation-binding sites on surfaces have been shown to provide a basis for the design of chemoresponsive LCs, the cations have been found to dissociate from the surfaces and dissolve slowly into LCs, resulting in time-dependent changes in the properties of LC-solid interfaces (which impacts the reliability of devices incorporating such surfaces). Here, we explore the use of surfaces comprising metal-coordinating polymers to minimize the dissolution of metal cations into LCs and characterize the impact of the interfacial environment created by the coordinating polymer on the ordering and time-dependent properties of LCs. In particular, by combining theoretical (electronic structure calculations) and experimental (polarization-modulation infrared reflection-adsorption spectroscopy) results, we determine that the pyridine groups of a thin film of poly(4-vinylpyridine-co-divinylbenzene) (P(4VP-co-DVB)) coordinate with Ni2+ when Ni(ClO4)2 is deposited onto the film. We provide evidence that the Ni2+-pyridine coordination weakens the binding of Ni2+ with 4'-n-pentyl-4-biphenylcarbonitrile (5CB), a room-temperature nematic LC, as compared to Ni(ClO4)2 supported on glass, although binding is still sufficiently strong to induce a homeotropic (perpendicular) orientation of the LC. Exposure of the 5CB films supported on Ni(ClO4)2-decorated P(4VP-co-DVB) substrates to parts-per-million vapor concentrations of dimethylmethylphosphonate (DMMP) was found to trigger orientational transitions (to planar (parallel) orientations) in the LC films. In contrast, 5CB supported on Ni(ClO4)2-decorated glass surfaces exhibited no response, even though displacement of 5CB by DMMP is predicted by computations to be thermodynamically favored in both cases. We propose that the distinct LC responses measured on glass and the coordinating polymer substrates are governed by the kinetics of displacement of 5CB by DMMP, a proposal that is supported by measurements performed with increasing temperature. Importantly, by using Ni2+ supported on P(4VP-co-DVB), we measured the ordering of 5CB to be stable and long-lived (>7 days), in contrast to unstable LC ordering (<14 h) when using Ni2+ supported on glass under dry conditions and at room temperature. We further demonstrate the stability of Ni(ClO4)2 supported on P(4VP-co-DVB) toward higher temperatures and humidity using E7 as the LC. Overall, these results demonstrate that metal-coordinating polymer films are a promising class of substrates for fabricating robust and long-lived chemoresponsive LCs.

The ability to synthesize shape-controlled polymer particles will benefit a wide range of applications including targeted drug delivery and metamaterials with reconfigurable structures, but existing synthesis approaches are commonly multistep and limited to a narrow size/shape range. Using a novel single-step synthesis technique, a variety of shapes including nanospheres, hemispherical micro-domes, orientation-controlled microgels, microspheres, spheroids, and micro-discs were obtained. The shape-controlled particles were synthesized by polymerizing divinylbenzene (DVB) via initiated chemical vapor deposition (iCVD) in nematic liquid crystals (LC). iCVD continuously and precisely delivered vapor-phase reactants, thus avoiding disruption of the LC structure, a critical limitation in past LC-templated polymerization. That shape controllability was further enabled by leveraging LC as a real-time display of the polymerization conditions and progression, using a custom in-situ long-focal range microscope. Detailed image analysis unraveled key mechanisms in polymer synthesis in LC. Poor solubilization by nematic LC led to the formation of pDVB nanospheres, distinct from microspheres obtained in isotropic solvents. The nanospheres precipitated to the LC-solid interface and further aggregated into microgel clusters with controlled orientation that was guided by the LC molecular alignment. On further polymerization, microgel clusters phase separated to form microspheres, spheroids, and unique disc-shaped particles.

Multidimensional solitons are prevalent in numerous research fields. In orientationally ordered soft matter system, three-dimensional director solitons exemplify the localized distortion of molecular orientation. However, their precise manipulation remains challenging due to unpredictable and uncontrolled generation. Here, we utilize preimposed programmable photopatterning in nematics to control the kinetics of director solitons. This enables both unidirectional and bidirectional generation at specific locations and times, confinement within micron-scaled patterns of diverse shapes, and directed propagation along predefined trajectories. A focused dynamical model provides insight into the origins of these solitons and aligns closely with experimental observations, underscoring the pivotal role of anchoring conditions in soliton manipulation. Our findings pave the way for diverse fundamental research avenues and promising applications, including microcargo transportation and optical information processing.

Shape morphing is vital to locomotion in microscopic organisms but has been challenging to achieve in sub-millimetre robots. By overcoming obstacles associated with miniaturization, we demonstrate microscopic electronically configurable morphing metasheet robots. These metabots expand locally using a kirigami structure spanning five decades in length, from 10 nm electrochemically actuated hinges to 100 μm splaying panels making up the 1 mm robot. The panels are organized into unit cells that can expand and contract by 40