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Abstract Lithium–gas batteries (LGBs) have garnered significant attention due to their impressive high‐energy densities and unique gas conversion capability. Nevertheless, the practical application of LGBs faces substantial challenges, including sluggish gas conversion kinetics inducing in low‐rate performance and high overpotential, along with limited electrochemical reversibility leading to poor cycle life. The imperative task is to develop gas electrodes with remarkable catalytic activity, abundant active sites, and exceptional electrochemical stability. Electrospinning, a versatile and well‐established technique for fabricating fibrous nanomaterials, has been extensively explored in LGB applications. In this work, we emphasize the critical structure–property for ideal gas electrodes and summarize the advancement of employing electrospun nanofibers (NFs) for performance enhancement in LGBs. Beyond elucidating the fundamental principles of LGBs and the electrospinning technique, we focus on the systematic design of electrospun NF‐based gas electrodes regarding optimal structural fabrication, catalyst handling and activation, and catalytic site optimization, as well as considerations for large‐scale implementation. The demonstrated principles and regulations for electrode design are expected to inspire broad applications in catalyst‐based energy applications.

Abstract Bifacial perovskite solar cells have shown great promise for increasing power output by capturing light from both sides. However, the suboptimal optical transmittance of back metal electrodes together with the complex fabrication process associated with front transparent conducting oxides have hindered the development of efficient bifacial PSCs. Here, we present a novel approach for bifacial perovskite devices using single-walled carbon nanotubes as both front and back electrodes. single-walled carbon nanotubes offer high transparency, conductivity, and stability, enabling bifacial PSCs with a bifaciality factor of over 98% and a power generation density of over 36%. We also fabricate flexible, all-carbon-electrode-based devices with a high power-per-weight value of 73.75 W g−1 and excellent mechanical durability. Furthermore, we show that our bifacial devices have a much lower material cost than conventional monofacial PSCs. Our work demonstrates the potential of SWCNT electrodes for efficient, stable, and low-cost bifacial perovskite photovoltaics.

IntroductionThe loose-patch clamp technique was first developed and used in native amphibian skeletal muscle (SkM), offering useful features complementing conventional sharp micro-electrode, gap, or conventional patch voltage clamping. It demonstrated the feedback effects of pharmacological modification of ryanodine receptor (RyR)-mediated Ca2+ release on the Na+ channel (Nav1.4) currents, initiating excitation–contraction coupling in native murine SkM. The effects of the further RyR and Ca2+-ATPase (SERCA) antagonists, dantrolene and cyclopiazonic acid (CPA), additionally implicated background tubular-sarcoplasmic Ca2+ domains in these actions.Materials and methodsWe extend the loose-patch clamp approach to ion current measurements in murine hippocampal brain slice cornu ammonis-1 (CA1) pyramidal neurons. We explored the effects on Na+ currents of pharmacologically manipulating RyR and SERCA-mediated intracellular store Ca2+ release and reuptake. We adopted protocols previously applied to native skeletal muscle. These demonstrated Ca2+-mediated feedback effects on the Na+ channel function.ResultsExperiments applying depolarizing 15 ms duration loose-patch clamp steps to test voltages ranging from −40 to 120 mV positive to the resting membrane potential demonstrated that 0.5 mM caffeine decreased inward current amplitudes, agreeing with the previous SkM findings. It also decreased transient but not prolonged outward current amplitudes. However, 2 mM caffeine affected neither inward nor transient outward but increased prolonged outward currents, in contrast to its increasing inward currents in SkM. Furthermore, similarly and in contrast to previous SkM findings, both dantrolene (10 μM) and CPA (1 μM) pre-administration left both inward and outward currents unchanged. Nevertheless, dantrolene pretreatment still abrogated the effects of subsequent 0.5- and 2-mM caffeine challenges on both inward and outward currents. Finally, CPA abrogated the effects of 0.5 mM caffeine on both inward and outward currents, but with 2 mM caffeine, inward and transient outward currents were unchanged, but sustained outward currents increased.ConclusionWe, thus, extend loose-patch clamping to establish pharmacological properties of murine CA1 pyramidal neurons and their similarities and contrasts with SkM. Here, evoked though not background Ca2+-store release influenced Nav and Kv excitation, consistent with smaller contributions of background store Ca2+ release to resting [Ca2+]. This potential non-canonical mechanism could modulate neuronal membrane excitability or cellular firing rates.

Abstract As implantable medical electronics (IMEs) developed for healthcare monitoring and biomedical therapy are extensively explored and deployed clinically, the demand for non‐invasive implantable biomedical electronics is rapidly surging. Current rigid and bulky implantable microelectronic power sources are prone to immune rejection and incision, or cannot provide enough energy for long‐term use, which greatly limits the development of miniaturized implantable medical devices. Herein, a comprehensive review of the historical development of IMEs and the applicable miniaturized power sources along with their advantages and limitations is given. Despite recent advances in microfabrication techniques, biocompatible materials have facilitated the development of IMEs system toward non‐invasive, ultra‐flexible, bioresorbable, wireless and multifunctional, progress in the development of minimally invasive power sources in implantable systems has remained limited. Here three promising minimally invasive power sources summarized, including energy storage devices (biodegradable primary batteries, rechargeable batteries and supercapacitors), human body energy harvesters (nanogenerators and biofuel cells) and wireless power transfer (far‐field radiofrequency radiation, near‐field wireless power transfer, ultrasonic and photovoltaic power transfer). The energy storage and energy harvesting mechanism, configurational design, material selection, output power and in vivo applications are also discussed. It is expected to give a comprehensive understanding of the minimally invasive power sources driven IMEs system for painless health monitoring and biomedical therapy with long‐term stable functions.

Abstract Organic semiconductors are a promising material candidate for X‐ray detection. However, the low atomic number (Z) of organic semiconductors leads to poor X‐ray absorption thus restricting their performance. Herein, the authors propose a new strategy for achieving high‐sensitivity performance for X‐ray detectors based on organic semiconductors modified with high –Z heteroatoms. X‐ray detectors are fabricated with p‐type organic semiconductors containing selenium heteroatoms (poly(3‐hexyl)selenophene (P3HSe)) in blends with an n‐type fullerene derivative ([6,6]‐Phenyl C71 butyric acid methyl ester (PC70BM). When characterized under 70, 100, 150, and 220 kVp X‐ray radiation, these heteroatom‐containing detectors displayed a superior performance in terms of sensitivity up to 600 ± 11 nC Gy−1 cm−2 with respect to the bismuth oxide (Bi2O3) nanoparticle (NP) sensitized organic detectors. Despite the lower Z of selenium compared to the NPs typically used, the authors identify a more efficient generation of electron‐hole pairs, better charge transfer, and charge transport characteristics in heteroatom‐incorporated detectors that result in this breakthrough detector performance. The authors also demonstrate flexible X‐ray detectors that can be curved to a radius as low as 2 mm with low deviation in X‐ray response under 100 repeated bending cycles while maintaining an industry‐standard ultra‐low dark current of 0.03 ± 0.01 pA mm−2.

Summary: Rapid, reliable, sensitive, portable, and accurate diagnostics are required to control disease outbreaks such as COVID-19 that pose an immense burden on human health and the global economy. Here we developed a loop-mediated isothermal amplification (LAMP)-based electrochemical test for the detection of SARS-CoV-2 that causes COVID-19. The test is based on the oxidation-reduction reaction between pyrophosphates (generated from positive LAMP reaction) and molybdate that is detected by cyclic voltammetry using inexpensive and disposable carbon screen printed electrodes. Our test showed higher sensitivity (detecting as low as 5.29 RNA copies/μL) compared to the conventional fluorescent reverse transcriptase (RT)-LAMP. We validated our tests using human serum and saliva spiked with SARS-CoV-2 RNA and clinical (saliva and nasal-pharyngeal) swab samples demonstrating 100% specificity and 93.33% sensitivity. Our assay provides a rapid, specific, and sensitive test with an electrochemical readout in less than 45 min that could be adapted for point-of-care settings.

Abstract The electrocatalysts are widely applied in lithium–sulfur (Li–S) batteries to selectively accelerate the redox kinetics behavior of Li2S, in which bifunctional active sites are established, thereby improving the electrochemical performance of the battery. Considering that the Li–S battery is a complex closed “black box” system, the internal redox reaction routes and active sites cannot be directly observed and monitored especially due to the distribution of potential active‐site structures and their dynamic reconstruction. Empirical evidence demonstrates that traditional electrochemical test methods and theoretical calculations only probe the net result of multi‐factors on an average and whole scale. Herein, based on the amorphous TiO2‐x@Ni selective bifunctional model catalyst, these limitations are overcome by developing a system that couples the light field and in situ irradiated X‐ray photoelectron spectroscopy to synergistically convert the “black box” battery into a “see‐through” battery for direct observation of the charge transportation, thus revealing that amorphous TiO2‐x and Ni nanoparticle as the oxidation and reduction sites selectively promote the decomposition and nucleation of Li2S, respectively. This work provides a universal method to achieve a deeper mechanistic understanding of bidirectional sulfur electrochemistry.

Abstract Halide perovskite materials have been extensively explored for their unique electrical, optical, magnetic, and catalytic properties. Most notably, solar cells based on perovskite thin films have improved their power conversion efficiency from 3.8% to over 25% during the last 12 years. However, it is still a challenge to develop a perovskite-based ink, suitable for upscaling the fabrication process of high-quality perovskite films with extreme purity, good crystallinity, and complete coverage over the deposition area. This is particularly important if the perovskite films are to be used for the scaled production of optoelectronic devices. Therefore, to make halide perovskites commercially available for various applications, it is vital to develop a reliable and highly robust deposition method, which can then be transferred to industry. Herein, the development of perovskite precursor inks suitable for use at low-temperature and vacuum-free solution-based deposition processes is reported. These inks can be further tailored according to the requirements of the deposition method, i.e., we propose their use with the industrially viable deposition technique called “slot-die coating”. Furthermore, a route for the preparation of low-cost and high-volume manufacturing of perovskite films on both rigid and flexible substrates is suggested in this paper. The presented approach is suitable for the fabrication of any functional layers of perovskites, that can be employed in various scaled applications, and it seeks the potential and the methodology for perovskite film deposition that is scalable to industrial standards.

Electrochemical energy storage (EES) devices are expected to play a critical role in achieving the global target of “carbon neutrality” within the next two decades. Potassium‐ion batteries (KIBs), with the advantages of low cost and high operating voltage, and they could become a major component of the required energy‐material ecosystems. Carbon‐based materials have shown promising properties as anode materials for KIBs. However, the key limitation of carbon anodes lies in the dramatic mechanical stress originating from large volume fluctuation during the (de)potassiation processes, which further results in electrode pulverization and rapid fading of cycling performance. Here, a controllable self‐assembly strategy to synthesize uniform dual‐heteroatom doped mesoporous carbon sphere (DMCS) anodes with unique radial pore channels is reported. This approach features a modified Stöber method combined with the single‐micelle template from the molecule‐level precursor design. The DMCS anodes demonstrate exceptional rate capability and ultrahigh cycling stability with no obvious degradation over 12 000 cycles at 2 A g−1, which is one of the most stable anodes. Furthermore, finite element simulations quantitatively verify the stress‐buffering effect of the DMCS anodes. This work provides a strategy from the perspective of stress evolution regulation for buffering mechanical stress originating from large volume fluctuations in advanced KIBs electrodes.

Abstract The realistic application of lithium–sulfur (Li–S) batteries has been severely hindered by the sluggish conversion kinetics of polysulfides (LiPS) and inhomogeneous deposition of Li2S at high sulfur loading and low electrolyte/sulfur ratio (E/S). Herein, a flexible Li–S battery architecture based on electrocatalyzed cathodes made of interfacial engineered TiC nanofibers and in situ grown vertical graphene are developed. Integrated 1D/2D heterostructured electrocatalysts are realized to enable highly improved Li+ and electron transportation together with significantly enhanced affinity to LiPS, which effectively accelerate the conversion kinetics between sulfur species, and thus induce homogeneous deposition of Li2S in the catalyzed cathodes. Consequently, highly active electro‐electrocatalysts‐based cells exhibit remarkable rate capability at 2C with a high specific capacity of 971 mAh g−1. Even at ultra‐high sulfur loading and low E/S ratio, the battery still delivers a high areal capacity of 9.1 mAh cm−2, with a flexible pouch cell being demonstrated to power a LED array at different bending angles with a high capacity over 100 cycles. This work puts forward a novel pathway for the rational design of effective nanofiber electrocatalysts for cathodes of high‐performance Li–S batteries.

Abstract Vertical graphene (VG), possessing superior chemical, physical, and structural peculiarities, holds great promise as a building block for constructing a high‐energy density lithium‐sulfur (Li‐S) battery. Therefore, it is desirable to develop a new VG growth technique with a novel structure to enable wide applications. Herein, we devise a novel complex permittivity‐dependent plasma confinement‐assisted VG growth technique, via asymmetric growing a VG layer on one side of N‐doped carbon nanofibers for the first time, using a unique lab‐built high flux plasma‐enhanced chemical vapor deposition system, as a bifunctional nanofiber membrane to construct Li‐S batteries with low negative/positive (N/P) and electrolyte/sulfur (E/S) ratios. The unique nanofiber membrane could simultaneously protect the cathode and anode, enabling an excellent electrochemical performance with low N/P and E/S ratios in Li‐S batteries. Such a full cell delivers high gravimetric energy density and volumetric energy density of 340 Wh kg−1 and 547 Wh L−1, respectively, at low N/P (2:1) and E/S (4:1) ratios. Furthermore, a pouch cell achieves a high areal capacity of 7.1 mAh cm−2 at a sulfur loading of 6 mg cm−2. This work put forward a novel pathway for the design of high‐energy density Li‐S batteries.

Understanding the rules of life is one of the most important scientific endeavours and has revolutionised both biology and biotechnology. Remarkable advances in observation techniques allow us to investigate a broad range of complex and dynamic biological processes in which living systems could exploit quantum behaviour to enhance and regulate biological functions. Recent evidence suggests that these non-trivial quantum mechanical effects may play a crucial role in maintaining the non-equilibrium state of biomolecular systems. Quantum biology is the study of such quantum aspects of living systems. In this review, we summarise the latest progress in quantum biology, including the areas of enzyme-catalysed reactions, photosynthesis, spin-dependent reactions, DNA, fluorescent proteins, and ion channels. Many of these results are expected to be fundamental building blocks towards understanding the rules of life.

Abstract Biological effects of electromagnetic fields (EMFs) have previously been identified for cellular proliferation and changes in expression and conduction of diverse types of ion channels. The major effect elicited by EMFs seems to be directed toward Ca2+ homeostasis. This is particularly remarkable since Ca2+ acts as a central modulator in various signaling pathways, including, but not limited to, cell differentiation and survival. Despite this, the mechanisms underlying this modulation have yet to be unraveled. Here, we assessed the effect of EMFs on intracellular [Ca2+], by exposing HEK 293 cells to both radio‐frequency electromagnetic fields (RF‐EMFs) and static magnetic fields (SMFs). We detected a constant and significant increase in [Ca2+] subsequent to exposure to both types of fields. Strikingly, the increase was nulled by administration of 10 μM Thapsigargin, a blocker of sarco/endoplasmic reticulum Ca2+‐ATPases (SERCAs), indicating the involvement of the endoplasmic reticulum (ER) in EMF‐related modulation of Ca2+ homeostasis.

Carbon nanotubes (CNTs) have unique properties with promise to outperform the electrical characteristics of bulk copper, giving rise to its primary driver for use in electronic devices. The challenge still hindering their full exploitation stems from an inability to manufacture them to long lengths, resulting in a requirement to align and entwine them into a yarn or wire. There have been several methods presented in achieving this, however, the common disadvantage has been that they are only applicable to specific types and morphologies of CNTs. In the work reported here, using electrospinning as a universally applicable route for any CNT type, we re-engineer and optimise the various formulation, fabrication and processing steps required to manufacture CNT wires. Through a series of investigations using a materials agnostic approach, we experimentally probe the choice of solvent, surfactant and thermal treatment temperature of the CNT inks, demonstrating the CNT-type optimum using a range of commercially available single- double- and multiwalled CNTs. Finally, this allowed us to develop and probe an electrical conditioning process to further enhance the electrical performance, achieving the highest reported un-doped electrical conductivity of 36,000 S⋅m− 1 for electrospun CNT wires, or a specific conductivity of 0.2×106S·m−1/g·cm−3.

Abstract Lithium–sulfur (Li–S) batteries have been regarded as a promising next‐generation energy storage technology for their ultrahigh theoretical energy density compared with those of the traditional lithium‐ion batteries. However, the practical applications of Li–S batteries are still blocked by notorious problems such as the shuttle effect and the uncontrollable growth of lithium dendrites. Recently, the rapid development of electrospinning technology provides reliable methods in preparing flexible nanofibers materials and is widely applied to Li–S batteries serving as hosts, interlayers, and separators, which are considered as a promising strategy to achieve high energy density flexible Li–S batteries. In this review, a fundamental introduction of electrospinning technology and multifarious electrospinning‐based nanofibers used in flexible Li–S batteries are presented. More importantly, crucial parameters of specific capacity, electrolyte/sulfur (E/S) ratio, sulfur loading, and cathode tap density are emphasized based on the proposed mathematic model, in which the electrospinning‐based nanofibers are used as important components in Li–S batteries to achieve high gravimetric (WG) and volume (WV) energy density of 500 Wh kg−1 and 700 Wh L−1, respectively. These systematic summaries not only provide the principles in nanofiber‐based electrode design but also propose enlightening directions for the commercialized Li–S batteries with high WG and WV.

Abstract Curved X‐ray detectors have the potential to revolutionize diverse sectors due to benefits such as reduced image distortion and vignetting compared to their planar counterparts. While the use of inorganic semiconductors for curved detectors are restricted by their brittle nature, organic–inorganic hybrid semiconductors which incorporated bismuth oxide nanoparticles in an organic bulk heterojunction consisting of poly(3‐hexylthiophene‐2,5‐diyl) (P3HT) and [6,6]‐phenyl C71 butyric acid methyl ester (PC70BM) are considered to be more promising in this regard. However, the influence of the P3HT molecular weight on the mechanical stability of curved, thick X‐ray detectors remains less well understood. Herein, high P3HT molecular weights (>40 kDa) are identified to allow increased intermolecular bonding and chain entanglements, resulting in X‐ray detectors that can be curved to a radius as low as 1.3 mm with low deviation in X‐ray response under 100 repeated bending cycles while maintaining an industry‐standard dark current of

Summary: The endeavors to develop manufacturing methods that can enhance polymer and composite structures in spacecraft have led to much research and innovation over many decades. However, the thermal stability, intrinsic material stress, and anisotropic substrate properties pose significant challenges and inhibit the use of previously proposed solutions under extreme space environment. Here, we overcome these issues by developing a custom-designed, plasma-enhanced cross-linked poly(p-xylylene):diamond-like carbon superlattice material that enables enhanced mechanical coupling with the soft polymeric and composite materials, which in turn can be applied to large 3D engineering structures. The superlattice structure developed forms an integral part with the substrate and results in a space qualifiable carbon-fiber-reinforced polymer featuring 10–20 times greater resistance to cracking without affecting the stiffness of dimensionally stable structures. This innovation paves the way for the next generation of advanced ultra-stable composites for upcoming optical and radar instrument space programs and advanced engineering applications.

New materials and optimized fabrication techniques have led to steady evolution in large area electronics, yet significant advances come only with new approaches to fundamental device design. The multimodal thin‐film transistor introduced here offers broad functionality resulting from separate control of charge injection and transport, essentially using distinct regions of the active material layer for two complementary device functions, and is material agnostic. The initial implementation uses mature processes to focus on the device's fundamental benefits. A tenfold increase in switching speed, linear input–output dependence, and tolerance to process variations enable low‐distortion amplifiers and signal converters with reduced complexity. Floating gate designs eliminate deleterious drain voltage coupling for superior analog memory or computing. This versatile device introduces major new opportunities for thin‐film technologies, including compact circuits for integrated processing at the edge and energy‐efficient analog computation.

Abstract Vertically aligned carbon nanotubes (VACNTs) present an exciting avenue for nanoelectronics due to their predetermined orientation and exceptional transport capabilities along the tube length, with the potential to be employed in a variety of optoelectronic applications. However, growth of VACNTs using conventional chemical vapor deposition (CVD) methods requires elevated temperatures (>720 °C) and therefore, the suitability of commonly used transparent conductive oxide (TCO) glasses, such as fluorine‐doped tin oxide (FTO) and indium‐tin oxide (ITO), as the substrates for nanotube growth are limited by their temperature‐sensitive nature. Here, the successful growth of multi‐walled VACNTs directly onto commonly used TCO glasses, FTO and ITO, using the photo‐thermal chemical vapor deposition (PTCVD) growth method is reported. The benefit of reflection, within the infrared region, of the TCO substrate and the effect of surface roughness on the growth of VACNTs is investigated. The application of VACNTs on ITO in inverted planar perovskite solar cells is investigated, which shows superior charge transfer, larger grain sizes in the perovskite film, and a champion device efficiency approaching 16%.

Photoactive and semiconducting metal-organic frameworks are desirable for electrical and photoelectrical devices, but remain rare. Here Demets and co-workers design a naphthalene diimide and cobalt based MOF with anisotropic electrical semiconductivity and a high responsivity of 2.5 × 105 A W−1.

The data presented in this article is related to the research article entitled “Fabrication of air-stable, large-area, PCDTBT:PC70BM polymer solar cell modules using a custom built slot-die coater” (D.I. Kutsarov, E. New, F. Bausi, A. Zoladek-Lemanczyk, F.A. Castro, S.R.P. Silva, 2016) [1]. The repository name and reference number for the raw data from the abovementioned publication can be found under: https://doi.org/10.15126/surreydata.00813106. In this data in brief article, additional information about the absorption properties of PCDTBT:PC70BM layers deposited from a 12.5 mg/ml and 15 mg/ml photoactive layer dispersion are shown. Additionally, the best and average J-V curves of single cells, fabricated from the 10 and 15 mg/ml dispersions, are presented.