Mechanically and Thermally Guided, Honeycomb-like Nanocomposites with Strain-Insensitive High Thermal Conductivity for Stretchable Electronics.

Thermal management materials have become increasingly crucial for stretchable electronic devices and systems. Drastically different from conventional thermally conductive materials, which are applied at static conditions, thermal management materials for stretchable electronics additionally require strain-insensitive thermal conductivity, as they generally undergo cyclic deformation. However, realizing such a property remains challenging mainly because conventional thermally conductive polymer composites generally lack a mechanically guided design. Here, we report a honeycomb-like nanocomposite with a three-dimensional (3D) thermally conductive network fabricated by an arrayed ice-templating technique followed by elastomer infiltration. The hexagonal honeycomb-like structure with thin, compact walls (≈ 40 µm) endows our composite with a high through-plane thermal conductivity (≈ 1.54 W m-1 K-1) at an ultralow boron nitride nanosheet (BNNS) loading (≈ 0.85 vol %), with an enhancement factor of thermal conductivity up to 820% and thermal-insensitive strain up to 200%, which are 2.7 and 2 times higher than those reported in the literature. We report an intelligent strategy for the development of advanced thermal management materials for high-performance stretchable electronics.

Diagnosis and treatment of angiographically unclear coronary lesions.

Although selective coronary angiography is the gold standard diagnostic technique for coronary lesions, this method does not provide all information regarding pathophysiologic mechanisms. We herein describe a patient in their early 60s with a 3-month history of pronounced angina. Coronary angiography revealed a central line of illumination in the proximomedial segment of the right coronary artery, suggesting a chronic coronary dissection/recanalized thrombus, along with positive remodeling and TIMI grade 2 flow. Optical coherence tomography showed a recanalized thrombus and multiple lumens separated by thin septa. Because of the significantly reduced flow and signs of ischemia in the right coronary artery irrigation territory, we decided to perform percutaneous coronary intervention. Post-treatment optical coherence tomography indicated optimal apposition and expansion of the stents with positive remodeling of the blood vessel. We believe that decisions regarding treatment modalities should be guided by the presence or absence of ischemia. Lesions that are causing myocardial ischemia should be revascularized; otherwise, medical treatment can be utilized.

Investigation of the effect and mechanism of nanocellulose on soy protein isolate- konjac glucomannan composite hydrogel system.

To enrich the application of nanocomposite hydrogels, we introduced two types of nanocellulose (CNC, cellulose nanocrystals; CNF, cellulose nanofibers) into the soy protein isolate(SPI)- konjac glucomannan (KGM) composite hydrogel system, respectively. The similarities and differences between the two types of nanocellulose as textural improvers of composite gels were successfully explored, and a model was developed to elaborate their interaction mechanisms. Appropriate levels of CNC (1.0 %) and CNF (0.75 %) prolonged SPI denaturation within the system, exposed more buried functional groups, improved molecular interactions, and strengthened the honeycomb structural skeleton formed by KGM. The addition of CNC resulted in greater gel strength (SKC1 2708.53 g vs. Control 810.35 g), while the addition of CNF improved the elasticity (SKF0.75 1940.24 g vs. Control 405.34 g). This was mainly attributed to the reinforcement of the honeycomb-structured, water binding and trapping, and the synergistic effect of covalent (disulfide bonds) and non-covalent interactions (hydrogen bonds, ionic bonds) within the gel network. However, the balance and interactions between proteins and polysaccharides were disrupted in the composite system with excessive CNF addition (≥0.75 %), which broken the stability of the honeycomb-like structure. We expect this study will draw attention on potential applications of CNC and CNF in protein-polysaccharide binary systems and facilitate the creation of novel, superior, mechanically strength-regulated nanofiber composite gels.

Honeycomb-like structure (HLS) in the left anterior-descending coronary artery-recanalized thrombus demonstrated by intravascular ultrasound (IVUS) in a patient with polycythemia vera and thrombocythemia.

A 71 year old male patient who experienced acute myocardial infarction (AMI) 4 years ago and had a history of polycythemia vera and thrombocythemia was admitted because acute attack of chronic heart failure. Coronary angiography revealed an unusual filling defect in the middle segment of the left anterior descending (LAD) coronary artery and IVUS showed it is a HLS which is different from dissection or woven coronary artery. We review the recent literature of HLS in this article and further investigations are warranted for the optimal management of HLS.

Synthesis of Ni3S2 and MOF-Derived Ni(OH)2 Composite Electrode Materials on Ni Foam for High-Performance Supercapacitors.

Honeycomb-like Ni(OH)2/Ni3S2/Ni foam (NF) was fabricated via a two-step hydrothermal process and subsequent alkalization. Ni3S2 with a honeycombed structure was in-situ synthesized on the NF surface by a hydrothermal process. MOF-derived Ni(OH)2 nanosheets were then successfully grown on the Ni3S2/NF surface by a second hydrothermal process and alkaline treatment, and a large number of nanosheets were interconnected to form a typical honeycomb-like structure with a large specific surface area and porosity. As a binder-free electrode, the prepared honeycomb-like Ni(OH)2/Ni3S2/NF exhibited a high specific capacitance (2207 F·g-1 at 1 A·g-1, 1929.7 F·g-1 at 5 mV·s-1) and a remarkable rate capability and cycling stability, with 62.3% of the initial value (1 A·g-1) retained at 10 A·g-1 and 90.4% of the initial value (first circle at 50 mV·s-1) retained after 5000 cycles. A hybrid supercapacitor (HSC) was assembled with Ni(OH)2/Ni3S2/NF as the positive electrode and activated carbon (AC) as the negative electrode and exhibited an outstanding energy density of 24.5 Wh·kg-1 at the power density of 375 W·kg-1. These encouraging results render the electrode a potential candidate for energy storage.

Embedding of conductive Ag nanoparticles among honeycomb-like NiMn layered double hydroxide nanosheet arrays for ultra-high performance flexible supercapacitors.

Layered double hydroxides are considered promising electrode materials for the preparation of high-energy-density supercapacitors owing to their suitable microstructure and significant electrochemical properties. In this study, honeycomb-like NiMn-layered double-hydroxide (NiMn-LDH) nanosheet arrays with numerous electron/ion channels, a large number of active sites, considerable redox reversibility, and significant electrical conductivity were synthesized by combining Co2(OH)2CO3 nanoneedle arrays with NiMn-LDH nanosheet arrays and Ag nanoparticles on a carbon cloth (CC) substrate through a hydrothermal strategy (CC@Co2CH/NM-LDH-Ag). The fabricated CC@Co2CH/NM-LDH-Ag binder-free electrode exhibited a high specific capacitance of 10,976 mF cm-2 (3092F/g, 1391.4C g-1) at 2 mA cm-2 (1 A/g), and a high capacitance retention of 93.2 % after 10,000 cycles at a current density of 20 mA cm-2. In addition, a solid-state asymmetric supercapacitor (ASC) device assembled using CC@Co2CH/NM-LDH-Ag as the cathode possessed an ultrahigh energy density of 68.85 Wh kg-1 at a power density of 722.6 W kg-1, and two fabricated ASC units in series were able to power a multifunctional display for more than 30 min. Therefore, this study provides a new approach for the design and synthesis of high-performance flexible electrodes.

Spatially Confined Li Growth on Honeycomb-like Lithiophilic Layered Double Hydroxide Nanosheet Arrays toward a Stable Li Metal Anode.

A lithium metal anode (LMA) is appealing due to its high theoretical capacity and low electrochemical potential. Unfortunately, the practical application of LMAs is restricted by the uncontrollable Li dendrite growth and tremendous volume change. Herein, lithiophilic honeycomb-like layered double hydroxide (LDH) nanosheet arrays supported on a flexible carbon cloth (NiMn-LDHs NAs@CC) are synthesized as the Li host to spatially confine the Li deposition, guiding Li growth via a conformal and uniform manner. First, the lithiophilic NiMn-LDHs NAs as nucleation seeds render the CC substance outstanding lithiophilicity and reduce the nucleation barrier. The hierarchical honeycomb-like structure then directs the oriented Li deposition and provides an open channel for fast ion transport. Finally, the CC skeleton offers a high specific surface for decreasing the inhomogeneous distribution of the current density and enough space for alleviating the volume variations, synergistically inhibiting the dendritic Li growth. As a consequence, the NiMn-LDHs NAs@CC symmetric cell exhibits a low overpotential of less than 17 mV at 2 mA cm-2 and a long lifespan of 2100 h at 3 mA cm-2. In addition, when paired with the LiNiCoMnO2 (NCM111) cathode, the NiMn-LDHs NAs@CC@Li full cell presents enhanced cycling stability and rate capability in comparison to the CC@Li full cell, implying the great potential of the NiMn-LDHs NAs@CC in stabilizing the LMA.

N-Doped Honeycomb-like Ag@N-Ti3C2Tx Foam for Electromagnetic Interference Shielding.

To solve the pollution problem of electromagnetic waves, new electromagnetic shielding materials should meet the requirements of being lightweight with high electrical conductivity. In this work, the combination of silver (Ag) nanoparticles and nitrogen doping (N-doping) was expected to tune the electromagnetic and physical properties of Ti3C2Tx MXene, and the Ag@N-Ti3C2Tx composites were fabricated through the hydrothermal reactions. The nitrogen doped (N-doped) Ag@Ti3C2Tx composites showed a hollow structure with a pore size of 5 µm. The influence of N-doped degrees on the electromagnetic interference (EMI) shielding performance was investigated over 8-18 GHz. Therefore, the controlled N-doping composites exhibited reflection-based EMI shielding performance due to the electrical conductivity and the special three-dimensional (3D) honeycomb-like structure. The achieved average EMI shielding values were 52.38 dB at the X-band and 72.72 dB at the Ku-band. Overall, the Ag@N-Ti3C2Tx foam, due to its special 3D honeycomb-like structure, not only meets the characteristics of light weight, but also exhibits ultra-high-efficiency EMI shielding performance, revealing great prospects in the application of electromagnetic wave shielding field.

High-Performance Flexible Piezoresistive Sensor Based on Ti3C2Tx MXene with a Honeycomb-like Structure for Human Activity Monitoring.

Wearable and flexible pressure sensors have sparked great interest due to their unique capacity to conformally attach to the surface of the skin and quantify human activities into recordable electric signals. As a result, more and more research efforts are being devoted to developing high-sensitivity and cost-effective flexible sensors for monitoring an individual's state of activity. Herein, a high-performance flexible piezoresistive sensor was designed and fabricated by combing 2D transition metal carbides, nitrides, and carbonitrides (MXene) with a honeycomb-like structure formed by femtosecond filamentating pulses. The sensing mechanism is attributed to the change of the connecting conductive paths between the top interdigital electrodes and the bottom microstructured films coated with MXene. The obtained sensing device demonstrates high sensitivity of 0.61 kPa-1, relatively short response time, and excellent reliability and stability. Benefiting from the aforementioned extraordinary sensing performance, the sensor can be used with success to monitor tiny physiological signals, detect large deformations during human movement, and distinguish finger gestures, thus demonstrating its broad prospects in physiological analysis systems, health monitoring systems, and human-machine interaction.

Honeycomb-like cork activated carbon with ultra-high adsorption capacity for anionic, cationic and mixed dye: Preparation, performance and mechanism.

Herein, the cork activated carbon (CAC) with excellent adsorption performance for cationic dye, anionic dye, and mixed dye was obtained by a two-step pyrolysis method. The CAC exhibits a fluffy honeycomb structure consisted of porous carbon nanosheets (100-200 nm), ultra-high specific surface area (3402.68 m2/g), and well-developed hierarchical porous structure, which offers a great deal of adsorption sites and transport channels to dye molecules. The adsorption process of all the dyes onto CAC is better described by Langmuir isotherm model and pseudo-2nd-order kinetic model. The CAC shows ultra-high adsorption capacity for methylene blue (1283.99 mg/g), rhodamine B (4067.57 mg/g), methyl orange (2666.2 mg/g), and congo red (8920.61 mg/g), with an extremely low equilibrium adsorption time (∼10 min). Collectively, this study demonstrated the potential of converting waste cork into high value-added adsorbent for the efficient purification of dye wastewater.

Refractory hypertension secondary to renal artery stenosis with a honeycomb-like structure.

BACKGROUND: A honeycomb-like structure (HLS) is a rare abnormality characterized by a braid-like appearance. Angiograph and intravascular examination, including coherence tomography and intravascular ultrasound (IVUS), can further confirm the multiple intraluminal channels or honeycomb structure, which can also be described as looking like 'swiss cheese', a 'spider web' or a 'lotus root'. Previous studies have mostly reported this abnormality in coronary arteries, with a few cases in renal arteries. More information about the characteristics and development of HLS is needed. CASE PRESENTATION: A 69-year-old Han man with resistant hypertension received abdominal enhanced computerised tomography and was revealed to have left renal artery stenosis with the possibility of left renal infarction. Renal artery angiography confirmed a 95% stenosis located in the proximal segment of the left renal artery, and the middle segment was blurred with multi-channel-like blood flow. Further IVUS was performed and identified multiple channels surrounded by fibrous tissue. It was a rare case of HLS in the renal artery secondary to the thrombus, with organisation and recanalisation. Balloon dilatation and stent implantation at the proximal segment of the left renal artery were performed successfully. Blood pressure was well controlled after the procedure. CONCLUSIONS: The IVUS findings are helpful for forming interventional therapeutic strategies for HLS lesions in the renal artery.

Directionally Tailoring Macroporous Honeycomb-Like Structured Carbon Nanofibers toward High-Capacitive Potassium Storage.

Constructing high-capacitive potassium storage materials can avoid the sluggish and unstable bulk diffusion process via a surface-induced process, which is conducive to swift and frequent potassium storage. Herein, we demonstrated the use of macroporous honeycomb-like carbon nanofibers (MHCNFs) as an excellent anode material for high-capacitive potassium storage. The as-made MHCNFs feature abundant well-controlled macropores, an amorphous structure, and a large specific surface area of around 595.9 m2 g-1. These structural characteristics could significantly reduce the transferring distance of electrons/ions, offer abundant active sites, enable high-capacitive contribution, and thus substantially improve the kinetics and structural stability of MHCNFs. Experimental investigation demonstrated that MHCNFs enable ultrahigh potassium storage ability (329.1 mAh g-1 at 100 mA g-1) and competitive rate capability (168.5 mAh g-1 at 5000 mA g-1). More impressively, even when cycled at 1000 mA g-1, the robust structure of MHCNFs can still enable the electrodes a capacity of 252.6 mAh g-1 over repeating 2500 cycles. This work offers a promising strategy that macropore engineering coupled with amorphous structure can make effectively elevated K+ diffusion kinetic performance and promoted K+ adsorption/intercalation storage possible.

Self-Assembly Lightweight Honeycomb-Like Prussian Blue Analogue on Cu Foam for Lithium Metal Anode.

As a next-generation anode material for lithium batteries, Li metal anode suffers from inherent drawbacks such as infinite volume expansion and uneven Li plating/stripping. Herein, we propose a lightweight lithiophilic Prussian blue analogue (PBA) with honeycomb-like structure on Cu foam by self-assembly method to address these issues. The unique honeycomb-like architecture could provide enlarged surface areas and abundant deposition sites for homogenizing Li+ flux during Li plating. Consequently, the elaborate PBA-decorated Cu foam current collector enables long-term (1800 h) reversible plating/stripping behavior and an observably improved Coulombic efficiency (98.3% after 350 cycles). The concept of the direct self-assembly synthesis method on metal foam provides new insights into the design of a lightweight 3-dimensional current collector for Li metal anode.

The Evolution in Electrochemical Performance of Honeycomb-Like Ni(OH)2 Derived from MOF Template with Morphology as a High-Performance Electrode Material for Supercapacitors.

Ni(OH)2 derived from an MOF template was synthesized as an electrode material for supercapacitors. The electrochemical performance of the electrode was adjusted by effectively regulating the morphology of Ni(OH)2. The evolution of electrochemical performance of the electrode with morphology of Ni(OH)2 was highlighted in detail, based on which honeycomb-like Ni(OH)2 was successfully synthesized, and endowed the electrode with outstanding electrochemical performance. For the three-electrode testing system, honeycomb-like Ni(OH)2 exhibited a very high specific capacitance (1865 F·g-1 at 1 A·g-1, 1550 F·g-1 at 5 mV·s-1). Moreover, it also presented an excellent rate capability and cycling stability, due to 59.46 % of the initial value (1 A·g-1) being retained at 10 A·g-1, and 172% of initial value (first circle at 50 mV·s-1) being retained after 20,000 cycles. With respect to the assembled hybrid supercapacitor, honeycomb-like Ni(OH)2 also displayed superior electrochemical performance, with a high energy density (83.9 Wh·kg-1 at a power density of 374.8 W·kg-1). The outstanding electrochemical performance of Ni(OH)2 should be attributed to its unique honeycomb-like structure, with a very high specific surface area, which greatly accelerates the transformation and diffusion of active ions.

Honeycomb-like structure in spontaneous recanalized coronary thrombus demonstrated by serial angiograms: a case report.

BACKGROUND: The honeycomb-like structure (HLS) is a rare cause of myocardial ischaemia characterized by multiple communicating channels divided by thin septa. The aetiology of this specific structure remains speculative. CASE SUMMARY: A 55-year-old man was admitted due to worsening effort angina during the previous 2 months. Diagnostic coronary angiography revealed occlusion of the distal right coronary artery (RCA) with good collateral flow from the left coronary artery. We considered this lesion as a recent total occlusion, and planned a percutaneous coronary intervention (PCI). At the time of PCI, 7 days after admission, an angiogram showed a spontaneous recanalization of the occlusive RCA. Intravascular ultrasound (IVUS) depicted a HLS at the recanalized lesion, including atherosclerotic stenosis. We managed these lesions with drug-eluting stents. DISCUSSION: A recanalized thrombus may manifest as a HLS. In this case, the patient suffered from worsening effort angina during the previous 2 months, we confirmed a spontaneous recanalization of the occluded coronary lesion by serial angiographic images, and observed HLS adjacent to the atherosclerotic attenuated plaque by using high-resolution IVUS. Recanalized organizing thrombus is considered an entity of HLS. However, all previous studies on the HLS in vivo have detected the structure in an already recanalized state. Therefore, the aetiology remained speculative and evidence has been indirect. This present case demonstrates that recanalized atherosclerotic thrombosis might be one of the causes of HLS.

Honeycomb-like structure-tunable chitosan-based porous carbon microspheres for methylene blue efficient removal.

Chitosan (CS) can be used for the preparation of carbon materials with different morphologies due to its excellent properties, but there are no reports on its spherical morphology. In this study, a feasible step-by-step strategy was proposed to fabricate nitrogen-containing chitosan-based porous carbon microspheres (CPCM) in HCl and KOH. The unique spherical morphology and honeycomb-like porous structure of CPCM were accurately regulated. A great quantity of micro/mesopores endowed CPCM an ultra-high specific surface area up to 2463.9 m2 g-1. Moreover, CPCM exhibited an ultra-high maximum adsorption capacity up to 1599.03 mg g-1 for methylene blue (MB), meanwhile the adsorption process was in well agreement with the Langmuir isotherm and pseudo-second-order kinetic models. It was simultaneously a favorable reusable adsorbent with high regenerative capacity. The high dye adsorption properties suggest that chitosan can be a promising candidate for sewage treatment in the form of carbon microspheres.

Significant enhancement of electron transfer from Shewanella oneidensis using a porous N-doped carbon cloth in a bioelectrochemical system.

Modifying the surface of an anode can improve electron transfer, thus enhancing the performance of the associated bioelectrochemical system. In this study, a porous N-doped carbon cloth electrode was obtained via a simple thermal reduction and etching treatment, and then used as the anode in a bioelectrochemical system. The electrode has a high nitrogen-to­carbon (N/C) ratio (~3.9%) and a large electrochemically active surface area (145.4 cm2, about 4.4 times higher than that of the original carbon cloth), which increases the bacterial attachment and provides more active sites for extracellular electron transfer. Electrochemical characterization reveals that the peak anodic current (0.71 mA) of the porous N-doped carbon cloth electrode in riboflavin is 18 times higher than that of the original carbon cloth electrode (0.04 mA), confirming the presence of more electroactive sites for the redox reaction. We also obtained a maximum current density of 0.29 mA/cm2 during operation of a bioelectrochemical system featuring the porous N-doped carbon cloth electrode, which is 14.5 times higher than that of the original carbon cloth electrode. This result demonstrates that the adoption of our new electrode is a viable strategy for boosting the performance of bioelectrochemical systems.

Honeycomb-like structure in the right coronary artery treated with a drug-eluting stent: a case report and literature review.

A honeycomb-like structure (HLS) is a rare entity encountered in catheterization laboratories. The etiology of HLS remains elusive. Moreover, no treatment guideline or consensus for HLS has been proposed. However, with more frequent adoption of intravascular imaging modalities, the number of cases of HLS is rising. We herein present a case of HLS and summarize previous reports in the literature with the aim of providing useful information for interventional cardiologists and promoting further research.