Electrochemical reduction of nitrate to hydroxylamine on gold electrode.

In this study, we explore the efficacy of gold (Au) as a selective electrocatalyst for the reduction of nitrate to hydroxylamine, a valuable nitrogen-based chemical, while also evaluating the by-product formation of ammonia. We systematically optimized various experimental parameters including nitrate concentration, pH, and applied potential. We found that at an applied potential of -0.7 V vs. RHE in 0.1 M HNO3, Au achieves a 230.1 ± 19 µmol NH2OH h-1 cm-2 yield, with a 34.2 ± 2.8% faradaic efficiency. This study underscores the potential of Au as an efficient and selective electrocatalyst for generating value-added nitrogen products through an electrochemical pathway.

Rapid Photothermal-Responsive Soft Hydrogel Actuator Contained Ti3C2Tx MXene and Laponite Clay with Enhanced Mechanical Properties.

Photothermal responsive hydrogels are widely used in bionic soft actuators due to their remote-controlled capabilities and flexibility. However, their weak mechanical properties and limited responsiveness hinder their potential applications. To overcome this, we developed an innovative laponite/MXene/PNIPAm (LxMyPN) nanocomposite hydrogel that is mechanically robust and exhibits excellent photothermally responsive properties based on abundant hydrogen bonds. Notably, laponite clay is used as a co-cross-linking agent to improve the mechanical properties of LxMyPN hydrogel, while MXene nanosheets are added to promote the photothermal responsiveness. The resulting L3M0.4PN nanocomposite hydrogel exhibits enhanced mechanical properties, with a compressive strength of 0.201 MPa, a tensile strength of 90 kPa, and a fracture toughness of 27.25 kJ m-2. In addition, the L3M0.4PN hydrogel displays a deswelling ratio of 73.6% within 60 s and experiences an excellent volume shrinkage of 82.4% under light irradiation. Furthermore, hydrogel actuators with fast response behaviors are constructed and employed as grippers capable of grasping and releasing target objects. Overall, this high-strength and fast-responsive hydrogel actuator is beneficial to paving the way for remote controlled soft robots.

Single-atom catalysts for electrocatalytic nitrate reduction into ammonia.

Ammonia (NH3) is a versatile and important compound with a wide range of uses, which is currently produced through the demanding Haber-Bosch process. Electrocatalytic nitrate reduction into ammonia (NRA) has recently emerged as a sustainable approach for NH3synthesis under ambient conditions. However, the NRA catalysis is a complex multistep electrochemical process with competitive hydrogen evolution reaction that usually results in poor selectivity and low yield rate for NH3synthesis. With maximum atom utilization and well-defined catalytic sites, single atom catalysts (SACs) display high activity, selectivity and stability toward various catalytic reactions. Very recently, a number of SACs have been developed as promising NRA electrocatalysts, but systematical discussion about the key factors that affect their NRA performance is not yet to be summarized to date. This review focuses on the latest breakthroughs of SACs toward NRA catalysis, including catalyst preparation, catalyst characterization and theoretical insights. Moreover, the challenges and opportunities for improving the NRA performance of SACs are discussed, with an aim to achieve further advancement in developing high-performance SACs for efficient NH3synthesis.

Electrochemical Reduction of CO2 into Syngas by N-Modified NiSb Nanowires.

Carbon dioxide reduction reaction (CO2RR) provides a promising method for syngas synthesis. However, it is challenging to balance the CO2RR activity and hydrogen (H2)/carbon monoxide (CO) ratios due to the limited mass transport and inefficient catalytic interface. Herein, we adopt a nitrogen (N)-modification method to synthesize N-modified nickel antimony nanowires (N-NiSb NWs/C), which are efficient for producing syngas with controllable H2/CO ratios. Significantly, the optimized N-NiSb NWs/C, with boosted electrochemical CO2RR activity, have the flexibility to control H2/CO ratios in syngas from nearly 1 to 4 in a wide potential range. The mechanistic discussion shows that the electronic structure of NiSb NWs/C can be optimized by using the synergistic effect between Ni and Sb, as well as the reasonable surface modification, so that a controllable syngas can be obtained. Our design provides an ideal platform for generating syngas with widely controllable H2/CO ratios.

Atomically Dispersed Iridium on Polyimide Support for Acidic Oxygen Evolution.

Designing a high-performing iridium (Ir) single-atom catalyst is desired for acidic water electrolysis, which shows enormous potential given its high catalytic activity toward acidic oxygen evolution reaction (OER) with minimum usage of precious Ir metal. However, it still remains a substantial challenge to stabilize the Ir single atoms during the OER operation without sacrificing the activity. Here, we report a high-performing OER catalyst by immobilizing Ir single atoms on a polyimide support, which exhibits a high mass activity on a carbon paper electrode while simultaneously achieving outstanding stability with negligible decay for 360 h. The resulting electrode (denoted as Ir1-PI@CP) reaches a 49.7-fold improvement in mass activity compared to the counterpart electrode prepared without polyimide support. Both our experimental and theoretical results suggest that, owing to the strong metal-support interactions, the polyimide support can enhance the Ir 5d states of Ir single atoms in Ir1-PI@CP, which can tailor the adsorption energies of intermediates and decrease the thermodynamic barrier at the rate-determining step of the OER, but also facilitate the proton-electron-transfer process and improve the reaction kinetics. This work offers an alternative avenue for developing single-atom catalysts with superior activity and durability toward various catalytic systems and beyond.

Metachronous multifocal carcinoma: A case report.

BACKGROUND: The incidence of multiple primary carcinomas (MPC) varies greatly, ranging from 0.73% to 11.70% in foreign countries, with duo-duplex carcinoma being the most common, trio-duplex carcinoma and above being rare, and simultaneous multigenic carcinoma being even rarer, accounting for 18.4% to 25.3% of the incidence of MPC. However, there is no report regarding patients presenting with simultaneous dual-origin carcinoma of the liver and colon and heterochronous pancreatic cancer. CASE SUMMARY: We report a special case of multifocal carcinoma, in which one patient had a medical condition of primary liver and colon cancer and pancreatic cystadenocarcinoma 2 years after surgery. Through aggressive advanced fluorescent laparoscopic techniques, standardized immunotherapy, targeting, and chemotherapy, a better prognosis and a desirable survival period were achieved for the patient. CONCLUSION: There is a need to clarify the nature of MPC through advanced surgical means to ensure better diagnosis and treatment.

Dynamical Janus Interface Design for Reversible and Fast-Charging Zinc-Iodine Battery under Extreme Operating Conditions.

Aqueous zinc (Zn) iodine (I2) batteries have emerged as viable alternatives to conventional metal-ion batteries. However, undesirable Zn deposition and irreversible iodine conversion during cycling have impeded their progress. To overcome these concerns, we report a dynamical interface design by cation chemistry that improves the reversibility of Zn deposition and four-electron iodine conversion. Due to this design, we demonstrate an excellent Zn-plating/-stripping behavior in Zn||Cu asymmetric cells over 1000 cycles with an average Coulombic efficiency (CE) of 99.95%. Moreover, the Zn||I2 full cells achieve a high-rate capability (217.1 mA h g-1 at 40 A g-1; C rate of 189.5C) at room temperature and enable stable cycling with a CE of more than 99% at -50 °C at a current density of 0.05 A g-1. In situ spectroscopic investigations and simulations reveal that introducing tetraethylammonium cations as ion sieves can dynamically modulate the electrode-electrolyte interface environment, forming the unique water-deficient and chloride ion (Cl-)-rich interface. Such Janus interface accounts for the suppression of side reactions, the prevention of ICl decomposition, and the enrichment of reactants, enhancing the reversibility of Zn-stripping/-plating and four-electron iodine chemistry. This fundamental understanding of the intrinsic interplay between the electrode-electrolyte interface and cations offers a rational standpoint for tuning the reversibility of iodine conversion.

Ultrathin NiO nanosheets anchored to a nitrogen-doped dodecahedral carbon framework for aqueous potassium-ion hybrid capacitors.

Hierarchical porous structures and well-modulated interfacial interactions are essential for the performance of electrode materials. The energy storage performance can be promoted by regulating the diffusion behavior of the electrolyte and constructing a coupled interaction at heterogeneous interfaces. Herein, we have synthesized ultrathin NiO nanosheets anchored to nitrogen-doped hierarchical porous carbon (NiO/N-HPC) and applied it to construct aqueous potassium ion hybrid capacitors (APIHCs). The abundant and interconnected porous architecture promotes electrolyte penetration/diffusion and shortens the ion transport path, thereby accelerating storage reaction kinetics. The nitrogen-doped carbon support can achieve optimized metal oxides-carbon interaction and enhance the adsorption ability for the electrolyte ions, leading to earning higher storage capacity. Consequently, the prepared NiO/N-HPC exhibits a superior capacitance of 126.4 F g-1 at a current density of 0.5 A g-1, and the as-fabricated NiO/N-HPC//N-HPC APIHC achieves an ultra-high capacitance retention of 91.6% over 8000 cycles at a current density of 2 A g-1. Meanwhile, the APIHC device shows an excellent energy density of 21.95 W h kg-1 and a power density of 9000 W kg-1.

Charge Redistribution in High-Entropy Perovskite Oxide Porous Nanotubes Boosts Nitrate Electroreduction to Ammonia.

High-entropy perovskite oxides are promising materials in the field of electrocatalysis due to their advantages such as large spatial composition regulation, entropy effects, and tunable material properties. However, the preparation of high-entropy perovskite oxides with stable and controllable structures still remains challenging. Herein, we fabricated a series of high-entropy perovskite oxide porous nanotubes (PNTs) by electrospinning as efficient electrocatalysts for the nitrate reduction reaction (NO3RR). We further revealed that the different diffusion and decomposition behaviors of metal ions and polymers during the calcination process are the key to the formation of high-entropy perovskite oxide PNTs. Especially, LaSrNiCoMnFeCuO3 PNTs show excellent performance of the NO3RR, achieving the maximum NH3 Faradaic efficiency of almost 100%, yield rate of 1657.5 µg h-1 mgcat.-1, and durable stability after successive cycling, being one of the best electrocatalysts for the NO3RR. The mechanism studies show that the charge redistribution induced by the multisite synergistic effect and abundant unsaturated sites in the high-entropy perovskite oxide PNTs favors the adsorption of NO3- and key intermediates and reduces the catalytic energy barrier, thus further achieving high NO3- conversion efficiency.

Viscoelastic Adhesive, Super-Conformable, and Semi-Flowable Liquid Metal Eutectogels for High-Fidelity Electrophysiological Monitoring.

Integrating gels with human skin through wearables provides unprecedented opportunities for health monitoring technology and artificial intelligence. However, most conductive hydrogels, organogels, and ionogels lack essential environmental stability, biocompatibility, and adhesion for reliable epidermal sensing. In this study, we have developed a liquid metal eutectogel simultaneously possessing superior viscoelasticity, semiflowability, and mechanical rigidity for low interfacial skin impedance, high skin adhesion, and durability. Liquid metal particles (LMPs) are employed to generate free radicals and gallium ions to accelerate the polymerization of acrylic acid monomers in a deep eutectic solvent (DES), obtaining highly viscoelastic polymer networks via physical cross-linking. In particular, graphene oxide (GO) is utilized to encapsulate the LMPs through a sonication-assisted electrostatic assembly to stabilize the LMPs in DES, which also enhances the mechanical toughness and regulates the rheological properties of the eutectogels. Our optimized semi-flowable eutectogel exhibits viscous fluid behavior at low shear rates, facilitating a highly conformable interface with hairy skin. Simultaneously, it demonstrates viscoelastic behavior at high shear rates, allowing for easy peel-off. These distinctive attributes enable the successful applications of on-skin adhesive strain sensing and high-fidelity human electrophysiological (EP) monitoring, showcasing the versatility of these ionically conductive liquid metal eutectogels in advanced personal health monitoring.

High-Entropy Perovskite Oxides as a Family of Electrocatalysts for Efficient and Selective Nitrogen Oxidation.

Electrocatalytic nitrogen oxidation reaction (NOR) can convert nitrogen (N2) into nitrate (NO3-) under ambient conditions, providing an attractive approach for synthesis of NO3-, alternative to the current approach involving the harsh Haber-Bosch and Ostwald oxidation processes that necessitate high temperature, high pressure, and substantial carbon emission. Developing efficient NOR catalysts is a prerequisite, which remains a formidable challenge, owing to the weak activation/dissociation of N2. A variety of NOR electrocatalysts have been developed, but their NOR kinetics are still extremely sluggish, resulting in inferior Faradaic Efficiencies. Here, we report a high-entropy Ru-based perovskite oxide (denoted as Ru-HEP) that can function as a high-performance NOR catalyst and exhibit a high NO3- yield rate of 39.0 µmol mg-1 h-1 with a Faradaic Efficiency of 32.8%. Both our experimental results and theoretical calculations suggest that the high-entropy configuration of Ru-HEP perovskite oxide can markedly enhance the oxygen-vacancy concentration, where the Ru sites and their neighboring oxygen vacancies can serve as unsaturated centers and decrease the overall energy barrier for N2 electrooxidation, thereby leading to promoted NOR kinetics. This work presents an alternative avenue for promoting NOR catalysis on perovskite oxides through the high-entropy engineering strategy.

Human Skin-Mimicking Ionogel-Based Electronic Skin for Intelligent Robotic Sorting.

Creating bionic intelligent robotic systems that emulate human-like skin perception presents a considerable scientific challenge. This study introduces a multifunctional bionic electronic skin (e-skin) made from polyacrylic acid ionogel (PAIG), designed to detect human motion signals and transmit them to robotic systems for recognition and classification. The PAIG is synthesized using a suspension of liquid metal and graphene oxide nanosheets as initiators and cross-linkers. The resulting PAIGs demonstrate excellent mechanical properties, resistance to freezing and drying, and self-healing capabilities. Functionally, the PAIG effectively captures human motion signals through electromechanical sensing. Furthermore, a bionic intelligent sorting robot system is developed by integrating the PAIG-based e-skin with a robotic manipulator. This system leverages its ability to detect frictional electrical signals, enabling precise identification and sorting of materials. The innovations presented in this study hold significant potential for applications in artificial intelligence, rehabilitation training, and intelligent classification systems.

Surface charge modulation boosts electrocatalytic water splitting over iridium catalysts on a polyimide support.

Developing high-performance iridium (Ir)-based catalysts with minimal precious Ir metal is a significant but challenging step towards the acidic oxygen evolution reaction (OER). Here, we report a high-performance OER catalyst with Ir nanoparticles on a polyimide support, where the polyimide support can effectively modulate the electronic structures of the Ir active sites for decreased thermodynamic barriers, but also enrich the local proton concentration near the Ir active sites, enhancing the OER rates.

Altering the CO2 Electroreduction Pathways Towards C1 or C2+ Products via Engineering the Strength of Interfacial Cu-O Bond.

Copper (Cu)-based catalysts have established their unique capability for yielding wide value-added products from CO2. Herein, we demonstrate that the pathways of the electrocatalytic CO2 reduction reaction (CO2RR) can be rationally altered toward C1 or C2+ products by simply optimizing the coordination of Cu with O-containing organic species (squaric acid (H2C4O4) and cyclohexanehexaone (C6O6)). It is revealed that the strength of Cu-O bonds can significantly affect the morphologies and electronic structures of derived Cu catalysts, resulting in the distinct behaviors during CO2RR. Specifically, the C6O6-Cu catalysts made up from organized nanodomains shows a dominant C1 pathway with a total Faradaic efficiency (FE) of 63.7 % at -0.6 V (versus reversible hydrogen electrode, RHE). In comparison, the C4O4-Cu with an about perfect crystalline structure results in uniformly dispersed Cu-atoms, showing a notable FE of 65.8 % for C2+ products with enhanced capability of C-C coupling. The latter system also shows stable operation over at least 10 h with a high current density of 205.1 mA cm-2 at -1.0 VRHE, i.e., is already at the boarder of practical relevance. This study sheds light on the rational design of Cu-based catalysts for directing the CO2RR reaction pathway.

Interfacial Accumulation and Stability Enhancement Effects Triggered by Built-in Electric Field of SnO2/LaOCl Nanofibers Boost Carbon Dioxide Electroreduction.

Constructing a built-in interfacial electric field (BIEF) is an effective approach to enhance the electrocatalysts performance, but it has been rarely demonstrated for electrochemical carbon dioxide reduction reaction (CO2RR) to date. Herein, for the first time, SnO2/LaOCl nanofibers (NFs) with BIEF is created by electrospinning, exhibiting a high Faradaic efficiency (FE) of 100% C1 product (CO and HCOOH) at -0.9--1.1 V versus reversible hydrogen electrode (RHE) and a maximum FEHCOOH of 90.1% at -1.2 VRHE in H-cell, superior to the commercial SnO2 nanoparticles (NPs) and LaOCl NFs. SnO2/LaOCl NFs also exhibit outstanding stability, maintaining negligible activity degradation even after 10 h of electrolysis. Moreover, their current density and FEHCOOH are almost 400 mA cm-2 at -2.31 V and 83.4% in flow-cell. The satisfactory CO2RR performance of SnO2/LaOCl NFs with BIEF can be ascribed to tight interface of coupling SnO2 NPs and LaOCl NFs, which can induce charge redistribution, rich active sites, enhanced CO2 adsorption, as well as optimized Gibbs free energy of *OCHO. The work reveals that the BIEF will trigger interfacial accumulation and stability enhancement effects in promoting CO2RR activity and stability of SnO2-based materials, providing a novel approach to develop stable and efficient CO2RR electrocatalysts.

Thermally Conductive and UV-EMI Shielding Electronic Textiles for Unrestricted and Multifaceted Health Monitoring.

Skin-attachable electronics have garnered considerable research attention in health monitoring and artificial intelligence domains, whereas susceptibility to electromagnetic interference (EMI), heat accumulation issues, and ultraviolet (UV)-induced aging problems pose significant constraints on their potential applications. Here, an ultra-elastic, highly breathable, and thermal-comfortable epidermal sensor with exceptional UV-EMI shielding performance and remarkable thermal conductivity is developed for high-fidelity monitoring of multiple human electrophysiological signals. Via filling the elastomeric microfibers with thermally conductive boron nitride nanoparticles and bridging the insulating fiber interfaces by plating Ag nanoparticles (NPs), an interwoven thermal conducting fiber network (0.72 W m-1 K-1) is constructed benefiting from the seamless thermal interfaces, facilitating unimpeded heat dissipation for comfort skin wearing. More excitingly, the elastomeric fiber substrates simultaneously achieve outstanding UV protection (UPF = 143.1) and EMI shielding (SET > 65, X-band) capabilities owing to the high electrical conductivity and surface plasmon resonance of Ag NPs. Furthermore, an electronic textile prepared by printing liquid metal on the UV-EMI shielding and thermally conductive nonwoven textile is finally utilized as an advanced epidermal sensor, which succeeds in monitoring different electrophysiological signals under vigorous electromagnetic interference. This research paves the way for developing protective and environmentally adaptive epidermal electronics for next-generation health regulation.

Hollow Stair-Stepping Spherical High-Entropy Prussian Blue Analogue for High-Rate Sodium Ion Batteries.

Prussian blue analogues (PBAs) are considered to be one of the most suitable sodium storage materials, especially with the introduction of the high-entropy (HE) concept into their structure to further improve their various abilities. However, severe agglomeration of the HEPBA particles still limits the fast charging capabilities. Here, an HEPBA (Nax(FeMnCoNiCu)[Fe(CN)6]y□1-y·nH2O) with a hollow stair-stepping spherical structure has been prepared through the chemical etching process of the traditional cubic structure of HEPBA. Electrochemical characterization (sodium ion battery), kinetic analysis, and COMSOL Multiphysics simulations reveal that the nature of the high-entropy and the hollow stair-stepping spherical structure can greatly improve the diffusion behavior of Na+ ions. Moreover, the hollow structure effectively mitigates the volume change of HEPBA during SIBs operation, ultimately extending the lifespan. Consequently, the as-prepared HEPBA cathode exhibits excellent rate performance (126.5 and 76.4 mAh g-1 at 0.1 and 4.0 A g-1, respectively) and stable long-term capability (maintaining its 75.6% capacity after 1000 cycles) due to its unique structure. Furthermore, the waste of the etching process can easily be recycled to prepare more HEPBA product. This processing method holds great promise for designing nanostructures of advanced high-entropy Prussian blue analogues for sodium ion batteries.

Enhancement of PLA crystallization, transparency, and strength by adding the long aliphatic chains grafted CNC.

The combination of crystallization, transparency, and strength is still a challenge for broadening the application of polylactic acid (PLA) films, while it is also difficult to balance. In this work, the long aliphatic chains of octadecylamine (ODA) were grafted onto the surface of cellulose nanocrystal (CNC) by tannic acid oxidation self-polymerization and Michael addition/Schiff base reaction between polytannic acid and ODA. Furthermore, the ODA grafted CNC (g-CNC) was used as green reinforcement for the PLA matrix and a series of PLA/g-CNC nanocomposite films were prepared by the casting method. The DSC, WAXD, POM, UV-vis and stretching test were employed to examine the effect of g-CNC on the properties of the as-prepared PLA/g-CNC nanocomposite films. It shows that the g-CNC is effective to improve the melt crystallization rate of PLA from 11 min to 7.3 min. Most importantly, the crystal size of the PLA spherulites was significantly reduced due to the well dispersion in the amorphous PLA matrix, which would effectively improve the transmittance of the PLA films and synchronously realize the combination of crystallization (62 %) and transparency (80.6 %). Moreover, the improved crystallization could also enhance the heat deformation performance of the PLA films since the heat resistance is closely associated with the crystallinity. Besides, the grafted ODA long chains improve the compatibility between CNC and PLA, leading to the reinforcement of PLA matrix, where the tensile strength reaches 65.05 MPa from 44.31 MPa. Compared with the pristine CNC, the addition of g-CNC makes more comprehensive improvement in the properties of the PLA films.

Synergy of Weakly Solvated Electrolyte and LiF-Reinforced Interphase Enables Long-Term Operation of Li-Metal Batteries at Low Temperatures.

Hindered by the high diffusion energy barrier of Li+ in graphite anode layers, the low-temperature application of traditional Li-ion batteries is limited. Lithium metal without intercalation and with excellent specific capacity is expected to support battery operation at low temperatures. However, due to the low conductivity, high freezing point, and strong solvation energy of traditional carbonate electrolytes, the application of lithium-metal batteries at low temperatures remains challenged. In this paper, an all-ester-based ternary solvent electrolyte based on fluorinated carbonate and methyl acetate is developed to improve the cyclic efficiency of the Li-metal anode at subzero temperatures. Methyl acetate, with low viscosity and low freezing point, endows Li+ with efficient transfer in the bulk phase at low temperatures. Fluorinated cosolvent regulates the solvation structure, thereby facilitating Li+ desolvation while forming a LiF-rich solid electrolyte interphase. The electrolyte exhibits good compatibility with the Li-metal anode, as confirmed by the significantly reduced kinetic barrier of Li+ diffusion at the interface. The theoretical calculations suggest that anions occupy the dominant positions within the inner solvation sheath. The in situ/ex situ characterizations provide straightforward evidence of a dendrite-free Li-metal electrode during cycling. As a result, the symmetric Li||Li cell is able to cycle stably for thousands of hours at current densities of 0.5 mA cm-2 and 1 mAh cm-2. When paired with a LiFePO4 cathode, the battery at 0.2 C (1 C = 170 mA g-1) has a capacity retention of 95.4% after 200 cycles at -15 °C and 92.6% after 100 cycles at -20 °C, respectively.

Induced Anionic Functional Group Orientation-Assisted Stable Electrode-Electrolyte Interphases for Highly Reversible Zinc Anodes.

Dendrite growth and other side-reaction problems of zinc anodes in aqueous zinc-ion batteries heavily affect their cycling lifespan and Coulombic efficiency, which can be effectively alleviated by the application of polymer-based functional protection layer on the anode. However, the utilization rate of functional groups is difficult to improve without destroying the polymer chain. Here, a simple and well-established strategy is proposed by controlling the orientation of functional groups (─SO3H) to assist the optimization of zinc anodes. Depending on the electrostatic effect, the surface-enriched ─SO3H groups increase the ionic conductivity and homogenize the Zn2+ flux while inhibiting anionic permeation. This approach avoids the destruction of the polymer backbone by over-sulfonation and amplifies the effect of functional groups. Therefore, the modified sulfonated polyether ether ketone (H-SPEEK) coating-optimized zinc anode is capable of longtime stable zinc plating/stripping, and moreover an enhanced cycling steadiness under high current densities is also detected in a series of Zn batteries with different cathode materials, which achieved by the inclusion of H-SPEEK coating without causing any harmful effects on the electrolyte and cathode. This work provides an easy and efficient approach to further optimize the plating/stripping of cations on metal electrodes, and sheds lights on the scale-up of high-performance aqueous zinc-ion battery technology.