Field-Free Spin-Orbit Torque Magnetization Switching in a Single-Phase Ferromagnetic and Spin Hall Oxide.

Current-induced spin-orbit torque (SOT) offers substantial promise for the development of low-power, nonvolatile magnetic memory. Recently, a single-phase material concurrently exhibiting magnetism and the spin Hall effect has emerged as a scientifically and technologically interesting platform for realizing efficient and compact SOT systems. Here, we demonstrate external-magnetic-field-free switching of perpendicular magnetization in a single-phase ferromagnetic and spin Hall oxide SrRuO3. We delicately altered the local lattices of the top and bottom surface layers of SrRuO3, while retaining a quasi-homogeneous, single-crystalline nature of the SrRuO3 bulk. This leads to unbalanced spin Hall effects between the top and bottom layers, enabling net SOT performance within single-layer ferromagnetic SrRuO3. Notably, our SrRuO3 exhibits the highest SOT efficiency and lowest power consumption among all known single-layer systems under field-free conditions. Our method of artificially manipulating the local atomic structures will pave the way for advances in spin-orbitronics and the exploration of new SOT materials.

Overexpression of transmembrane TNFα in brain endothelial cells induces schizophrenia-relevant behaviors.

Upregulation of genes and coexpression networks related to immune function and inflammation have been repeatedly reported in the brain of individuals with schizophrenia. However, a causal relationship between the abnormal immune/inflammation-related gene expression and schizophrenia has not been determined. We conducted co-expression networks using publicly available RNA-seq data from prefrontal cortex (PFC) and hippocampus (HP) of 64 individuals with schizophrenia and 64 unaffected controls from the SMRI tissue collections. We identified proinflammatory cytokine, transmembrane tumor necrosis factor-α (tmTNFα), as a potential regulator in the module of co-expressed genes that we find related to the immune/inflammation response in endothelial cells (ECs) and/or microglia of the brain of individuals with schizophrenia. The immune/inflammation-related modules associated with schizophrenia and the TNF signaling pathway that regulate the network were replicated in an independent cohort of brain samples from 68 individuals with schizophrenia and 135 unaffected controls. To investigate the association between the overexpression of tmTNFα in brain ECs and schizophrenia-like behaviors, we induced short-term overexpression of the uncleavable form of (uc)-tmTNFα in ECs of mouse brain for 7 weeks. We found schizophrenia-relevant behavioral deficits in these mice, including cognitive impairment, abnormal sensorimotor gating, and sensitization to methamphetamine (METH) induced locomotor activity and METH-induced neurotransmitter levels. These uc-tmTNFα effects were mediated by TNF receptor2 (TNFR2) and induced activation of TNFR2 signaling in astrocytes and neurons. A neuronal module including neurotransmitter signaling pathways was down-regulated in the brain of mice by the short-term overexpression of the gene, while an immune/inflammation-related module was up-regulated in the brain of mice after long-term expression of 22 weeks. Our results indicate that tmTNFα may play a direct role in regulating neurotransmitter signaling pathways that contribute to the clinical features of schizophrenia.

Dielectric-Engineered High-Speed, Low-Power, Highly Reliable Charge Trap Flash-Based Synaptic Device for Neuromorphic Computing beyond Inference.

The coming of the big-data era brought a need for power-efficient computing that cannot be realized in the Von Neumann architecture. Neuromorphic computing which is motivated by the human brain can greatly reduce power consumption through matrix multiplication, and a device that mimics a human synapse plays an important role. However, many synaptic devices suffer from limited linearity and symmetry without using incremental step pulse programming (ISPP). In this work, we demonstrated a charge-trap flash (CTF)-based synaptic transistor using trap-level engineered Al2O3/Ta2O5/Al2O3 gate stack for successful neuromorphic computing. This novel gate stack provided precise control of the conductance with more than 6 bits. We chose the appropriate bias for highly linear and symmetric modulation of conductance and realized it with very short (25 ns) identical pulses at low voltage, resulting in low power consumption and high reliability. Finally, we achieved high learning accuracy in the training of 60000 MNIST images.

Acetylcholine titre regulation by non-neuronal acetylcholinesterase 1 and its putative roles in honey bee physiology.

Similar to other insects, honey bees have two acetylcholinesterases (AChEs), AmAChE1 and AmAChE2. The primary catalytic enzyme for acetylcholine (ACh) hydrolysis in synapses is AmAChE2, which is predominantly expressed in neuronal tissues, whereas AmAChE1 is expressed in both neuronal and non-neuronal tissues, with limited catalytic activity. Unlike constitutively expressed AmAChE2, AmAChE1 expression is induced under stressful conditions such as heat shock and brood rearing suppression, but its role in regulating ACh titre remains unclear. In this paper, to elucidate the role of AmAChE1, the expression of AmAChE1 was suppressed via RNA interference (RNAi) in AmAChE1-induced worker bees. The ACh titre measurement following RNAi revealed that the expression of AmAChE1 downregulated the overall ACh titre in all tissues examined without altering AmAChE2 expression. Transcriptome analysis showed that AmAChE1 knockdown upregulated protein biosynthesis, cell respiration, and thermogenesis in the head. These findings suggest that AmAChE1 is involved in decreasing neuronal activity, enhancing energy conservation, and potentially extending longevity under stressful conditions via ACh titre regulation.

Establishment and application of bioassay- and molecular marker-based methods for monitoring fluvalinate resistance of Varroa mites.

The Varroa mite, Varroa destructor, is an ectoparasite that infests honey bees. The extensive use of acaricides, including fluvalinate, has led to the emergence of resistance in Varroa mite populations worldwide. This study's objective is to monitor fluvalinate resistance in field populations of Varroa mites in Korea through both bioassay-based and molecular marker-based methods. To achieve this, a residual contact vial (RCV) bioassay was established for on-site resistance monitoring. A diagnostic dose of 200 ppm was determined based on the bioassay using a putative susceptible population. In the RCV bioassay, early mortality evaluation was effective for accurately discriminating mites with the knockdown resistance (kdr) genotype, while late evaluation was useful for distinguishing mites with additional resistance factors. The RCV bioassay of 14 field mite populations collected in 2021 indicated potential resistance development in four populations. As an alternative approach, quantitative sequencing was employed to assess the frequency of the L925I/M mutation in the voltage-gated sodium channel (VGSC), associated with fluvalinate kdr trait. While the mutation was absent in 2020 Varroa mite populations, it emerged in 2021, increased in frequency in 2022, and became nearly widespread across the country by 2023. This recent emergence and rapid spread of fluvalinate resistance within a span of three years demonstrate the Varroa mite's significant potential for developing resistance. This situation further underscores the urgent need to replace fluvalinate with alternative acaricides. A few novel VGSC mutations potentially involved in resistance were identified. Potential factors driving the rapid expansion of resistance were further discussed.

Investigation of Ca Insertion into α-MoO3 Nanoparticles for High Capacity Ca-Ion Cathodes.

Calcium-ion batteries (CIBs) are a promising alternative to lithium-ion batteries (LIBs) due to the low redox potential of calcium metal and high abundance of calcium compounds. Due to its layered structure, α-MoO3 is regarded as a promising cathode host lattice. While studies have reported that α-MoO3 can reversibly intercalate Ca ions, limited electrochemical activity has been noted, and its reaction mechanism remains unclear. Here, we re-examine Ca insertion into α-MoO3 nanoparticles with a goal to improve reaction kinetics and clarify the storage mechanism. The α-MoO3 electrodes demonstrated a specific capacity of 165 mA h g-1 centered near 2.7 V vs Ca2+/Ca, stable long-term cycling, and good rate performance at room temperature. This work demonstrates that, under the correct conditions, layered oxides can be a promising host material for CIBs and renews prospects for CIBs.

Atomic-scale mapper for superlattice photodetectors analysis.

In this work, a new Python-based tool for atomic-scale mapping of high-angle annular dark-field (HAADF) and annular bright-field (ABF) scanning transmission electron microscopy (STEM) images using the Z-contrast method is introduced, aimed to help in the analysis of superlattice layers' composition, and in the determination of material of interfaces. The operation principle of the program, as well as specific examples of use, are explained in many details. Good customization flexibility using the user-friendly graphical user interface (GUI), allows the processing of a wide range of images, demonstrating a decent accuracy of coordinates extraction and performance.

High-sensitivity waveguide-integrated bolometer based on free-carrier absorption for Si photonic sensors.

Conventional photon detectors necessarily face critical challenges regarding strong wavelength-selective response and narrow spectral bandwidth, which are undesirable for spectroscopic applications requiring a wide spectral range. With this perspective, herein, we overcome these challenges through a free-carrier absorption-based waveguide-integrated bolometer for infrared spectroscopic sensors on a silicon-on-insulator (SOI) platform featuring a spectrally flat response at near-infrared (NIR) range (1520-1620 nm). An in-depth thermal analysis was conducted with a systematic investigation of geometry dependence on the detectors. We achieved great performances: temperature coefficient of resistance (TCR) of -3.786%/K and sensitivity of -26.75%/mW with a low wavelength dependency, which are record-high values among reported waveguide bolometers so far, to our knowledge. In addition, a clear on-off response with the rise/fall time of 24.2/29.2 µs and a 3-dB roll-off frequency of ∼22 kHz were obtained, sufficient for a wide range of sensing applications. Together with the possibility of expanding an operation range to the mid-infrared (MIR) band, as well as simplicity in the detector architecture, our work here presents a novel strategy for integrated photodetectors covering NIR to MIR at room temperature for the development of the future silicon photonic sensors with ultrawide spectral bandwidth.

Flexoelectricity-Driven Mechanical Switching of Polarization in Metastable Ferroelectrics.

Flexoelectricity-based mechanical switching of ferroelectric polarization has recently emerged as a fascinating alternative to conventional polarization switching using electric fields. Here, we demonstrate hyperefficient mechanical switching of polarization exploiting metastable ferroelectricity that inherently holds a unique mechanical response. We theoretically predict that mechanical forces markedly reduce the coercivity of metastable ferroelectricity, thus greatly bolstering flexoelectricity-driven mechanical polarization switching. As predicted, we experimentally confirm the mechanical polarization switching via an unusually low mechanical force (100 nN) in metastable ferroelectric CaTiO_{3}. Furthermore, the use of low mechanical forces narrows the width of mechanically writable nanodomains to sub-10 nm, suggesting an ultrahigh data storage density of ≥1 Tbit cm^{-2}. This Letter sheds light on the mechanical switching of ferroelectric polarization as a viable key element for next-generation efficient nanoelectronics and nanoelectromechanics.

Selection of stable reference genes for quantitative real-time PCR in the Varroa mite, Varroa destructor.

To investigate the acaricide toxicity and resistance mechanisms in the Varroa mite, it is essential to understand the genetic responses of Varroa mites to acaricides, which are usually evaluated by transcriptional profiling based on quantitative real-time polymerase chain reaction (qPCR). In this study, to select reference genes showing consistent expression patterns regardless of the acaricide treatment or the type of tissue, Varroa mites treated with each of the three representative acaricides (coumaphos, fluvalinate, and amitraz) were processed for transcriptomic analysis, from which eight genes (NADH dehydrogenase [NADHD], glyceraldehyde-3-phosphate dehydrogenase [GAPDH], eukaryotic translation elongation factor 1 α 1 [eEF1A1], eukaryotic translation elongation factor 2 [eEF2], ribosomal protein L5 [RpL5], Actin, tubulin α-1D chain [α-tubulin], and Rab1) were selected as candidates. The transcription profiles of these genes, depending on the treatment of the three acaricides or across different tissues (cuticle, legs, gut/fat bodies, and synganglion), were analyzed using qPCR with four validation programs, BestKeeper, geNorm, NormFinder, and RefFinder. Following acaricide treatment, eEF1A1 and NADHD showed the least variation in their expression levels, whereas the expression levels of α-tubulin and RpL5 were the most stable across different tissue groups. Rab1/GAPDH and Actin/eEF2 showed the least stable expression patterns following acaricide treatments and across different tissues, respectively, requiring precautions for use. When vitellogenin gene expression was analyzed by different reference genes, its expression profiles varied significantly depending on the reference genes, highlighting the importance of proper reference gene use. Thus, it is recommended using eEF1A1 and NADHD as reference genes for the comparison of the effects of acaricide on the whole body, whereas α-tubulin and RpL5 are recommended for investigating the tissue-specific expression profiles of target genes.

Insecticide resistance in pepper greenhouse populations of Aphis gossypii (Hemiptera: Aphididae) in Korea.

The cotton aphid or melon aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is a polyphagous insect pest with a wide host range. Two distinct genetic clusters were found in A. gossypii populations in Korea. To determine whether the division of the genetic clusters was driven by insecticide selection pressure, the frequencies of insecticide resistance-associated mutations on three representative insecticide target genes [i.e., nicotinic acetylcholine receptor gene (nAChR), voltage-gated sodium channel gene (vgsc), and acetylcholinesterase 1 gene (ace-1)] were predicted in A. gossypii populations with known genetic structures. Most populations revealed heterozygosity-resistant alleles for the nAChR R81T and vgsc M918L mutations, but homozygous-resistant alleles for the ace-1 S431F mutation. However, assessment of the three mutation frequencies revealed no apparent correlation between the genetic structures and the resistance profiles. The regression analysis revealed no correlation between the genetic cluster ratios and resistance allele frequencies (R81T, S431F, and M918L). We used three insecticides that are commonly used in greenhouses: imidacloprid (neonicotinoid), acephate (organophosphate), and esfenvalerate (pyrethroid), to test resistance and susceptibility in A. gossypii populations. The bioassay results revealed that the BS_19 (Busan) and JE_19 (Jeongeup) populations were resistant to imidacloprid and acephate, the HS_19 (Honseong) population was resistant to acephate and esfenvalerate, and susceptible lab strains only exhibited resistance to acephate. The bioassay results were correlated with mutation frequency, but no correlation was detected among genetic clusters. These results suggest that the distinct genetic structure observed in the Korean populations of A. gossypii is not likely influenced by insecticide resistance traits, but rather by other factors.

Molecular and kinetic characterization of two acetylcholinesterases with particular focus on the roles of two amino acid substitutions (Y390N and F392W) in Bemisia tabaci.

Two acetylcholinesterases (AChEs) are present in Bemisia tabaci (BtAChE1 and BtAChE2). A conserved AChE mutation conferring organophosphate (OP) resistance (F392W in BtAChE1) is saturated in field populations despite its potential fitness cost, and a highly conserved amino acid residue forming the backdoor of AChE is substituted with a unique amino acid (Y390N in BtAChE1) in B. tabaci. Thus, the roles and relationships of the two amino acid substitutions in the evolutionary adaptation of B. tabaci remain to be elucidated, and little information is available on the catalytic and molecular properties of BtAChE1 and BtAChE2. To determine which AChE is a more relevant target of OPs and carbamates, the molecular and kinetic properties of BtAChE1 and BtAChE2 were investigated. Both BtAChE1 and BtAChE2 were exclusively expressed in head and thorax but not in abdomen, bound to the membrane via GPI anchoring, and present as dimeric forms. Soluble monomeric form was detected only in BtAChE2. The catalytic activity of baculovirus-expressed BtAChE1 was 19.5-fold higher than that of BtAChE2. The inhibition assay revealed that the F392W mutation in BtAChE1 enhanced resistance to OPs. The artificial substitution of N390 (wild form) to Y (putative ancient form) led to reduced catalytic efficiency and increased inhibition by glycoalkaloids, suggesting that the Y390N substitution in BtAChE1 may have been required for Solanaceae host adaptation. BtAChE1 was proven to function as a main catalytic enzyme for ACh hydrolysis, thus being the main target of OPs and carbamates.

Molecular and kinetic properties of three acetylcholinesterases in the Varroa mite, Varroa destructor.

The Varroa mite, Varroa destructor, poses one of the most serious threats to honey bees worldwide. Although coumaphos, an anticholinesterase pesticide, is widely used for varroa mite control, little information is available on the properties of Varroa mite acetylcholinesterases (VdAChEs). In this study, three putative VdAChEs were annotated and named VdAChE1, VdAChE2, and VdAChE3. All VdAChEs possessed most of the functionally important signature domains, suggesting that they are catalytically active. Phylogenetic analysis revealed that VdAChE1 was clustered into a clade containing most arthropod AChE1s, whereas VdAChE2 and VdAChE3 formed a unique clade with other arachnid AChEs. VdAChE1 was determined to be membrane-anchored, but both VdAChE2 and VdAChE3 are soluble, as judged by electrophoresis in conjunction with western blotting. Tissue-specific transcription profiling revealed that VdAChE1 was most predominantly expressed in the synganglion. In contrast, VdAChE2 was most predominantly expressed in the legs and cuticle. VdAChE3 showed negligible expression levels in all the tissues examined. In a kinetic analysis using recombinant VdAChEs, VdAChE1 exhibited the highest catalytic efficiency, followed by VdAChE2 and VdAChE3. Inhibition experiments revealed that VdAChE1 was most sensitive to all tested inhibitors. Taken together, VdAChE1 appears to be the major synaptic enzyme with a more toxicological relevance, whereas VdAChE2 is involved in other noncatalytic functions, including chemical defense against xenobiotics. Current findings contribute to a more detailed understanding of the evolutionary and functional traits of VdAChEs and to the design of novel anticholinesterase varroacides.

Arrayed MoS2 -In0.53 Ga0.47 As van der Waals Heterostructure for High-Speed and Broadband Detection from Visible to Shortwave-Infrared Light.

A high-speed and broadband 5 × 5 photodetector array based on MoS2 /In0.53 Ga0.47 As heterojunction is successfully demonstrated to take full advantage of the type-II band-aligned multilayer MoS2 /In0.53 Ga0.47 As. The fabricated devices exhibit good uniformity in the Raman spectrum and clear rectifying characteristics. The fabricated MoS2 /In0.53 Ga0.47 As photodetectors show good optical performances at a broad wavelength range showing high responsivities corresponding to the detectivity of ≈1010 Jones at -3 V for the incident broadband light from 400 to 1550 nm. A very fast photoresponse is also obtained with a small rise/fall time in the order of microseconds both for visible (638 nm) and shortwave infrared (1310 nm). Finally, the image scanning properties of MoS2 /In0.53 Ga0.47 As devices are demonstrated for visible and infrared light, indicating that the suggested device is one of the promising options for future broadband imager, which can be integrated on the focal plane arrays (FPAs).

Broadband Au/n-GaSb Schottky photodetector array with a spectral range from 300†nm to 1700nm.

A broadband photodetector is becoming increasingly important as a key element for multicolor imaging. We proposed an Au/n-GaSb Schottky photodetector (PD) array with a wide spectral range from ultraviolet (UV) to short-wavelength infrared (SWIR). The PD was formed by deposition of a 5 nm-thick Au layer on the n-type GaSb substrate and subsequent mesa array formation. The fabricated PD array has shown uniform electrical characteristics and good rectifying behaviors. From the photoresponse measurement, the PD has shown uniformly high external quantum efficiency (EQE) over a spectral range of 300 nm to 1700nm. The value of EQE was 35% at 300 nm and exceeded 50% in the IR region. Furthermore, the PD has shown a rapid rise time of 1.44 µs from the transient photoresponse measurement.

Tailoring bolometric properties of a TiOx/Ti/TiOx tri-layer film for integrated optical gas sensors.

In this paper, we systematically investigated tailoring bolometric properties of a proposed heat-sensitive TiOx/Ti/TiOx tri-layer film for a waveguide-based bolometer, which can play a significant role as an on-chip detector operating in the mid-infrared wavelength range for the integrated optical gas sensors on Ge-on-insulator (Ge-OI) platform. As a proof-of-concept, bolometric test devices with a TiOx single-layer and TiOx/Ti/TiOx tri-layer films were fabricated by varying the layer thickness and thermal treatment condition. Comprehensive characterization was examined by the scanning transmission electron microscopy (STEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) analyses in the prepared films to fully understand the microstructure and interfacial properties and the effects of thermal treatment. Quantitative measurements of the temperature- and time-dependent resistance variations were conducted to deduce the minimum detectable change in temperature (ΔTmin) of the prepared films. Furthermore, based on these experimentally obtained results, limit-of-detection (LoD) for the carbon dioxide gas sensing was estimated to demonstrate the feasibility of the proposed waveguide-based bolometer with the TiOx/Ti/TiOx tri-layer film as an on-chip detector on the Ge-OI platform. It was found that the LoD can reach ∼3.25 ppm and/or even lower with the ΔTmin of 11.64 mK in the device with the TiOx/Ti/TiOx (47/6/47 nm) tri-layer film vacuum-annealed at 400 °C for 15 min, which shows great enhancement of ∼7.7 times lower value compared to the best case of TiOx single-layer films. Our theoretical and experimental demonstration for tailoring bolometric properties of a TiOx/Ti/TiOx tri-layer film provides fairly useful insight on how to improve LoD in the integrated optical gas sensor with the bolometer as an on-chip detector.

Comparative advantages of a type-II superlattice barrier over an AlGaSb barrier for enhanced performance of InAs/GaSb LWIR nBn photodetectors.

The barrier layer in InAs/GaSb LWIR nBn detector is usually composed of AlGaSb alloy, which has a non-negligible valence band offset and is sensitive to chemical solutions. In this work, we investigated a type-II superlattice (T2SL) barrier that is homogeneous with the T2SL absorber layer in order to resolve these drawbacks of the AlGaSb barrier. The lattice mismatch of the T2SL barrier was smaller than that of the AlGaSb barrier. At -70mV and 80 K, the dark current density and the noise equivalent temperature difference of the nBn devices with the T2SL barrier were 4.4×10-6A/cm2 and 33 mK, respectively.

Bioinspired Photoresponsive Single Transistor Neuron for a Neuromorphic Visual System.

Realizing a neuromorphic-based artificial visual system with low-cost hardware requires a neuromorphic device that can react to light stimuli. This study introduces a photoresponsive neuron device composed of a single transistor, developed by engineering an artificial neuron that responds to light, just like retinal neurons. Neuron firing is activated primarily by electrical stimuli such as current via a well-known single transistor latch phenomenon. Its firing characteristics, represented by spiking frequency and amplitude, are additionally modulated by optical stimuli such as photons. When light is illuminated onto the neuron transistor, electron-hole pairs are generated, and they allow the neuron transistor to fire at lower firing threshold voltage. Different photoresponsive properties can be modulated by the intensity and wavelength of the light, analogous to the behavior of retinal neurons. The artificial visual system can be miniaturized because a photoresponsive neuronal function is realized without bulky components such as image sensors and extra circuits.

Cannabinoid Receptor Type 1 Regulates Drug Reward Behavior via Glutamate Decarboxylase 67 Transcription.

Interaction of cannabinoid receptor type 1 (CB1) and GABAergic neuronal activity is involved in drug abuse-related behavior. However, its role in drug-dependent Pavlovian conditioning is not well understood. In this study, we aimed to evaluate the effects of a CB1 agonist, JWH-210, on the development of conditioned place preference (CPP)-induced by methamphetamine (METH). Pretreatment with a synthetic cannabinoid, JWH-210 (CB1 agonist), increased METH-induced CPP score and METH-induced dopamine release in acute striatal slices. Interestingly, CB1 was expressed in glutamate decarboxylase 67 (GAD67) positive cells, and overexpression of CB1 increased GAD67 expression, while CB1 knockdown reduced GAD67 expression in vivo and in vitro. GAD67 is known as an enzyme involved in the synthesis of GABA. CB1 knockdown in the mice striatum increased METH-induced CPP. When GAD67 decreased in the mice striatum, mRNA level of CB1 did not change, suggesting that CB1 can regulate GAD67 expression. GAD67 knockdown in the mouse striatum augmented apomorphine (dopamine receptor D2 agonist)-induced climbing behavior and METH-induced CPP score. Moreover, in the human brain, mRNA level of GAD67 was found to be decreased in drug users. Therefore, we suggest that CB1 potentiates METH-induced CPP through inhibitory GABAergic regulation of dopaminergic neuronal activity.

High Volumetric and Gravimetric Capacity Electrodeposited Mesostructured Sb2 O3 Sodium Ion Battery Anodes.

Sodium ion batteries (SIBs) are considered promising alternatives to lithium ion batteries for grid-scale and other energy storage applications because of the broad geographical distribution and low cost of sodium relative to lithium. Here, fabrication and characterization of high gravimetric and volumetric capacity 3D Ni-supported Sb2 O3 anodes for SIBs are presented. The electrodes are prepared by colloidal templating and pulsed electrodeposition followed by heat treatment. The colloidal template is optimized to provide large pore interconnects in the 3D scaffold to enable a high active materials loading and accommodate a large volume expansion during cycling. An electrodeposited loading of 1.1 g cm-3 is chosen to enable a combined high gravimetric and volumetric capacity. At this loading, the electrodes exhibit a specific capacity of ≈445 mA h g-1 and a volumetric capacity of ≈488 mA h cm-3 with a capacity retention of 89% after 200 cycles at 200 mA g-1 . The stable cycling performance can be attributed to the 3D metal scaffold, which supports active materials undergoing large volume changes, and an initial heat treatment appears to improve the adhesion of the Sb2 O3 to the metal scaffold.