Pressureless Welding of Temperature-Invariant Multifunctionality Body Based on Hydroxyl-Functionalized Boron Nitride Nanosheets and Bifunctional Monoethanolamine Cross-linker.

Bulk hexagonal boron nitride (h-BN) ceramics with structural integrity, high-temperature resistance and low expansion rate are expected for multifunctional applications in extreme conditions. However, due to its sluggish self-diffusion and intrinsic inertness, it remains a great challenge to overcome high-energy barrier for h-BN powder sintering. Herein, a cross-linking and pressureless-welding strategy is reported to produce bulk boron nitride nanosheets (BNNSs) ceramics with well-crystalized and dense B-N covalent-welding frameworks. The essence of this synthesis strategy lies in the construction of >B─O─H2C─H2C─H2N:→B< bond bridge connection structure among hydroxyl functionalized BNNSs (BNNSs-OH) using bifunctional monoethanolamine (MEA) as cross-linker through esterification and intermolecular-coordination reactions. The prepared BNNSs-interlaced ceramics have densities not less than 1.2 g cm-3, and exhibit exceptional mechanical robustness and resiliency, excellent thermomechanical stability, ultra-low linear thermal expansion coefficient of 0.06 ppm °C-1, and high thermal diffusion coefficient of 4.76 mm2 s-1 at 25 °C and 3.72 mm2 s-1 at 450 °C. This research not only reduces the free energy barrier from h-BN particles to bulk ceramics through facile multi-step physicochemical reaction, but also stimulates further exploration of multifunctional applications for bulk h-BN ceramics over a wide temperature range.

Engineering O-O Species in Boron Nitrous Nanotubes Increases Olefins for Propane Oxidative Dehydrogenation.

Boron nitride (BN) has been widely studied as an efficient catalyst for oxidative propane dehydrogenation (OPDH). Oxygen-containing boron species (e.g., BO·, B(OH)xO3-x) are generally considered as the active centers in BN for OPDH. Here, we show an effective progressive substitution strategy toward the development of boron-oxygen-nitrogen nanotubes (BONNTs) enriched with O-O species as a highly active, selective, and stable catalyst for OPDH. At 525 °C, an olefin yield of 48.6% is achieved over BONNTs with a propane conversion of 64.4%, 2.8 times that of boron nitrogen nanotubes (BNNTs). Even after reaction for 150 h (475 °C), BONNTs exhibit good olefin yield. Both the B(OH)xO3-x and O-O species that coexist in the BONNT catalyst are demonstrated as active centers, which differs from the B(OH)xO3-x one in BNNTs. Based on catalytic results, propane and oxygen alternate treatment experiments, and theoretical calculations, the O-O center is more favorable for producing both propylene (C3=) and ethylene (C2=), which experiences a dehydration pathway and two possible reaction paths with a lower energy barrier to yield olefins, while B(OH)xO3-x is mainly responsible for producing few C3=.

Enhanced Adsorption of Polysulfides on Carbon Nanotubes/Boron Nitride Fibers for High-Performance Lithium-Sulfur Batteries.

Lithium-sulfur (Li-S) batteries are one of the most promising high-energy-density storage systems. However, serious capacity attenuation and poor cycling stability induced by the shuttle effect of polysulfide intermediates can impede the practical application of Li-S batteries. Herein we report a novel sulfur cathode by intertwining multi-walled carbon nanotubes (CNTs) and porous boron nitride fibers (BNFs) for the subsequent loading of sulfur. This structural design enables trapping of active sulfur and serves to localize the soluble polysulfide within the cathode region, leading to low active material loss. Compared with CNTs/S, CNTs/BNFs/S cathodes deliver a high initial capacity of 1222 mAh g-1 at 0.1 C. Upon increasing the current density to 4 C, the cell retained a capacity of 482 mAh g-1 after 500 cycles with a capacity decay of only 0.044 % per cycle. The design of CNTs/BNFs/S gives new insight on how to optimize cathodes for Li-S batteries.

Synthesis of Perovskite CsPbBr3 Quantum Dots/Porous Boron Nitride Nanofiber Composites with Improved Stability and Their Reversible Optical Response to Ammonia.

All-inorganic CsPbX3 (X = Cl, Br, I) perovskite quantum dots (QDs) have great potential for various applications due to their excellent photoluminescence properties. However, poor stability under long-term storage hinders their applications. Herein we report the utilization of porous boron nitride nanofibers (BNNFs) as a promising carrier for anchoring of CsPbBr3 QDs. Due to the good dispersion and immobilization of CsPbBr3 QDs, the resulting CsPbBr3/BNNF composites show excellent photostability and superior long-term storage stability in an air environment. Moreover, the CsPbBr3/BNNF composites exhibit an interesting ammonia-responsive behavior: i.e., a distinct decrease in photoluminescence intensity upon exposure to ammonia gas and the subsequent photoluminescence recovery after post-treatment in nitrogen gas. Even after treatment with ammonia gas for 3 h, the composites can still be recovered under nitrogen gas treatment. The fast response, reversibility, and stability of CsPbBr3/BNNF composites in the presence of ammonia gas could inspire a broader range of applications.

Distinct Dasatinib-Induced Mechanisms of Apoptotic Response and Exosome Release in Imatinib-Resistant Human Chronic Myeloid Leukemia Cells.

Although dasatinib is effective in most imatinib mesylate (IMT)-resistant chronic myeloid leukemia (CML) patients, the underlying mechanism of its effectiveness in eliminating imatinib-resistant cells is only partially understood. This study investigated the effects of dasatinib on signaling mechanisms driving-resistance in imatinib-resistant CML cell line K562 (K562R(IMT)). Compared with K562 control cells, exsomal release, the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/ mammalian target of rapamycin (mTOR) signaling and autophagic activity were increased significantly in K562R(IMT) cells and mTOR-independent beclin-1/Vps34 signaling was shown to be involved in exosomal release in these cells. We found that Notch1 activation-mediated reduction of phosphatase and tensin homolog (PTEN) was responsible for the increased Akt/mTOR activities in K562R(IMT) cells and treatment with Notch1 γ-secretase inhibitor prevented activation of Akt/mTOR. In addition, suppression of mTOR activity by rapamycin decreased the level of activity of p70S6K, induced upregulation of p53 and caspase 3, and led to increase of apoptosis in K562R(IMT) cells. Inhibition of autophagy by spautin-1 or beclin-1 knockdown decreased exosomal release, but did not affect apoptosis in K562R(IMT) cells. In summary, in K562R(IMT) cells dasatinib promoted apoptosis through downregulation of Akt/mTOR activities, while preventing exosomal release and inhibiting autophagy by downregulating expression of beclin-1 and Vps34. Our findings reveal distinct dasatinib-induced mechanisms of apoptotic response and exosomal release in imatinib-resistant CML cells.

Photochemical Synthesis of Ultrafine Cubic Boron Nitride Nanoparticles under Ambient Conditions.

Cubic boron nitride (c-BN) is a super-hard material whose hardness increases dramatically with decreasing size. However, c-BN nanoparticles (NPs) with sizes less than 10 nm have never been obtained. Herein we report a simple strategy towards the synthesis of ultrafine c-BN NPs with an average size of 3.5 nm. The method, under ambient conditions, exploits a laser-induced photochemical effect and employs dioxane solution of ammonia borane (AB) as a liquid target. Meanwhile, total dehydrogenation of AB is realized by laser irradiation. Therefore, this approach shows great potential for the preparation of super-hard NPs as well as controllable dehydrogenation.

Boron carbon nitride as efficient oxygen reduction reaction support.

The electrocatalytic oxygen reduction reaction (ORR) is crucial for energy conversion systems such as fuel cells and metal-air batteries. Boron carbon nitrogen (BCN) is a novel functional material with a high specific surface area, excellent corrosion resistance, and outstanding electrochemical stability. These properties make BCN an effective ORR catalyst and a promising support for metal catalysts. This study leveraged the strong interaction between BCN and metals to anchor platinum nanoparticles (Pt NPs) onto the BCN surface (Pt/BCN), significantly enhancing the durability of traditional Pt/C catalysts in ORR. The half-wave potential of Pt/BCN is 0.927 V, higher than Pt/XC-72R (0.857 V) and commercial Pt/C (0.879 V). Notably, after 10,000 durability test cycles, the mass activity (MA) of Pt/XC-72R and commercial Pt/C decreased by 67 % and 75 %, respectively. Even after 50,000 cycles, Pt/BCN exhibited only a 54 % decrease in MA. Experimental data and density functional theory calculations confirmed increased electron transfer from Pt to the BCN support, indicating a strong electronic metal-support interaction (EMSI) between Pt and BCN. This strong EMSI effectively anchored the Pt NPs, preventing migration and aggregation during the ORR process. Consequently, our research introduces a novel electrocatalyst support material with significant potential for ORR and broader applications.

Electronic Structure Modification of MnO2 Nanosheet Arrays with Enhanced Water Oxidation Activity and Stability by Nitrogen Plasma.

The strategic design of catalysts for the oxygen evolution reaction (OER) is crucial in tackling the substantial energy demands associated with hydrogen production in electrolytic water splitting. Despite extensive research on birnessite (δ-MnO2) manganese oxides to enhance catalytic activity by modulating Mn3+ species, the ongoing challenge is to simultaneously stabilize Mn3+ while improving overall activity. Herein, oxygen (O) vacancies and nitrogen (N) doping have been simultaneously introduced into the MnO2 through a simple nitrogen plasma approach, resulting in efficient OER performance. The optimized N-MnO2v electrocatalyst exhibits outstanding OER activity in alkaline electrolyte, reducing the overpotential by nearly 160 mV compared to pure pristine MnO2 (from 476 to 312 mV) at 10 mA cm-2, and a small Tafel slope of 89 mV dec-1. Moreover, it demonstrates excellent durability over a 122 h stability test. The introduction of O vacancies and incorporation of N not only fine-tune the electronic structure of MnO2, increasing the Mn3+ content to enhance overall activity, but also play a crucial role in stabilizing Mn3+, thereby leading to exceptional stability over time. Subsequently, density functional theory calculations validate the optimized electronic structure of MnO2 achieved through the two engineering methods, effectively lowering the intermediate adsorption free energy barrier. Our synergistic approach, utilizing nitrogen plasma treatment, opens a pathway to concurrently enhance the activity and stability of OER electrocatalysts, applicable not only to Mn-based but also to other transition metal oxides.

Measurement of 224Ra in water via pulsed ionization chamber (PIC) radon detector.

224Ra (t1/2 = 3.6 d) has been widely used as a tracer in environmental water research. Here, we present a new method for measuring 224Ra in natural waters using a pulsed ionization chamber (PIC)-based radon detector. This method is based on the measurement of the 224Ra daughter isotope 220Rn (thoron) after reaching secular equilibrium within 7 min. Radium isotopes are concentrated on ''Mn-fibers'' before measurement of 220Rn, which can be distinguished from 222Rn by the difference in their half-lives. The measurement efficiency of the method is 0.20 ± 0.01 cps/Bq at an optimum airflow rate of 1.0 L/min and a water/Mn-fiber weight ratio of 1.0. Results from natural water samples obtained by this method agree well with analysis via RaDeCC, an established technique for 224Ra assessments. Since the PIC system is lighter compared to RaDeCC, easier to operate, and does not require the usage of helium carrier gas and desiccant, this method is recommended for in-situ 224Ra measurement in long-term fieldwork with limited logistical support.

Porous boron nitride with a high surface area: hydrogen storage and water treatment.

We report on the synthesis of high-quality microporous/mesoporous BN material via a facile two-step approach. An extremely high surface area of 1687 m(2) g(-1) and a large pore volume of 0.99 cm(3) g(-1) have been observed in the synthesized BN porous whiskers. The formation of the porous structure was attributed to the group elimination of organic species in a BN precursor, melamine diborate molecular crystal. This elimination method maintained the ordered pore structure and numerous structural defects. The features including high surface area, pore volume and structural defects make the BN whiskers highly suitable for hydrogen storage and wastewater treatment applications. We demonstrate excellent hydrogen uptake capacity of the BN whiskers with high weight adsorption up to 5.6% at room temperature and at the relatively low pressure of 3 MPa. Furthermore, the BN whiskers also exhibit excellent adsorption capacity of methyl orange and copper ions, with the maximum removal capacity of 298.3 and 373 mg g(-1) at 298 K, respectively.

Heparin-induced thrombocytopenia in Chinese patients: 240 patients study in one center.

BACKGROUND: The study was conducted in order to analyze the incidence of heparin-induced thrombocytopenia (HIT) and heparin-induced thrombocytopenia and thrombosis syndrome (HITTS) in 240 patients from the Department of Vascular Surgery in China, to evaluate the current laboratory detection technique, and to explore the feasibility for the technique to be developed in China. METHODS: 240 patients receiving unfractionated heparin (UFH) were studied in one center. Before and after the UFH treatment, platelet count, HIT-antibody ELISA test, and heparin-induced platelet aggregation (HIPA) were tested. RESULTS: Among 240 patients, HIT was diagnosed in 36 cases. The incidence was 15%. HITTS occurred in 6 cases (2.5%). The median time of thrombocytopenia was the 8th day. Platelet counts recovered to normal level in 3 - 6 days after heparin withdrawal CONCLUSIONS: The incidence of HIT is higher; however, the incidence of HITTS is lower. Monitoring platelet count, which is simple and easy to do and available in hospitals at different levels (township hospital included), is a reliable method to diagnose HIT early. The HIT-antibody ELISA test could be introduced in specific hospitals to prescreen HIT. In view of the higher sensitivity and specificity of HIPA, it can be used in larger diagnostic centers in all the big cities of China.

Condensation-assembly synthesis of three-dimensionally porous boron nitride for effective oil removal.

A template-free pyrolysis route has been developed using condensation-assembly precursors made of trimethoxyboroxane (TMB) and melamine (M) to cater the requirements of an industrial real-world environment. The precursors contain abundant B-N bonds and exhibit a high level of interconnectivity, resulting in 3D-PBN with enhanced mechanical properties and the ability to be easily customized in terms of shape. Moreover, 3D-PBN demonstrates rapid adsorption kinetics and excellent reusability, efficiently removing up to 270% of its own weight of fuel within 30 s and being readily regenerated through simple calcination. Even after undergoing 50 cycles, the mechanical properties remain at a remarkable 80%, while the adsorption performance exceed 95%. Furthermore, a comprehensive analysis of thermal behavior from precursor to 3D-PBN has been conducted, leading to the proposal of a molecular-scale evolution process comprising four major steps. This understanding enables us to control the phase reaction and regulate the composition of the products, which is crucial for determining the characteristics of the final product.

Effects of intrathecally administered interferon α on chronic constriction injury model rats' mechanical pain threshold and G protein expression in the spinal cord.

INTRODUCTION: The aim of the study was to explore the analgesic mechanism of effects of intrathecally administered interferon a (IFN-a) on chronic constriction injury (CCI) model rats. MATERIAL AND METHODS: 24 rats were divided into 6 groups, with 4 rats in each group, including the negative control group (Group N, no operation or treatment), the sham operation group (Group S, only the left sciatic nerve of the rats was exposed without ligation, 0.9% NaCl was intrathecally administered), and four experimental groups (CCI model was established first and then different drugs were intrathecally administered respectively), including 0.9% NaCl (Group C), IFN-a (Group CI), morphine (Group CM), and IFN-a combined with morphine (Group CIM). The mRNA levels of G proteins in both the spinal cord and dorsal root ganglia (DRG), as well as the content of amino acid and chemokine (C-X-C motif) ligand 6 (CXCL-6) in the cerebrospinal fluid were measured and analysed in each group. RESULTS: Intrathecal administration of IFN-a increased the mechanical pain threshold in CCI rats (33.32 ±1.36 vs. 21.08 ±1.59, p < 0.001), achieving the effect comparable to that of morphine (33.32 ±1.36 vs. 32.44 ±3.18, p > 0.05), increased the mRNA expression level of Gi protein (0.62 ±0.04 vs. 0.49 ±0.05, p = 0.006), and decreased the mRNA expression level of Gs protein in the spinal cord (1.80 ±0.16 vs. 2.06 ±0.15, p = 0.035) and DRG (2.11 ±0.10 vs. 2.79 ±0.13, p < 0.001). The intrathecal administration of both IFN-a and morphine can reduce the glutamate content in the cerebrospinal fluid (261.55 ±38.12 vs. 347.70 ±40.69, p = 0.012), but without any statistically significant difference in the content of CXCL-6 across all groups ( p > 0.05). CONCLUSIONS: Intrathecal injection of IFN-a improved the mechanical pain threshold in CCI rats, so we inferred that intrathecal administration of IFN-a had analgesic effects on neuropathic pain, possibly related to the activation of G-proteincoupled µ receptors in the spinal cord and the inhibition of glutamate release.

Highly Multifunctional Performances of Boron Nitride Nanosheets/Polydimethylsiloxane Composite Foams.

Although this kind of hexagonal boron nitride (h-BN)-filled polydimethylsiloxane (PDMS) multifunctional composite foam has been greatly expected, its development is still relatively slow as a result of the limitation of synthetic challenge. In this work, a new foaming process of BNNSs-PDMS, alcohol, and water three-phase emulsion system is employed to synthesize a series of high-quality BNNSs/PDMS composite foams (BSFs) filled with highly functional and uniformly distributed BNNSs. As a result of well-bonded interfaces between the BNNSs and PDMS, enhanced multiple functions of BSFs appeared. The BSFs can show complete resilience at a compressive strain of 90% and only 3.99% irreversible deformation after 100,000 compressing-releasing hyperelastic cycles at a strain of 60%. On the basis of their outstanding shape-memory properties, the maximum voltage value of compression-driven piezo-triboelectric (CDPT) responses of the BSFs is up to ∼20 V. Depending on the remarkable super-elastic and CDPT performances, the BSFs can be used for sensitive sensing of temperature difference and electromechanical responses. Also, in the range of 12-40 GHz, the BSF materials display ultralow dielectric constants between 1.1 and 1.4 with proper dielectric loss tangent values of <0.3 and exhibit an enhanced and broadened sound adsorption capacity ranging from 500 to 6500 Hz. Although BSFs have high porosities of >65%, their thermal conductivities can still reach up to 0.407 ± 0.039 W m-1 K-1. Moreover, the BSF materials display favorable thermal stability, obviously reduced coefficient of thermal expansion, and good flame retardancy. All of these properties render the BSFs as a new category of excellent multifunctional material.

Boron Nitride Microspheres via Pyrolysis of Polymerized Precursors.

Microspheric BN materials have high application potential because they have better fluidity and dispersion ability to endow hexagonal boron nitride (h-BN) ceramics and h-BN/polymer composites with highly desired performance. In this work, a novel synthetic route to the BN microspheres has been developed by means of a controllable pyrolysis of polymerized spherical precursors. The precursor formation mechanism is proposed to be the F-127-induced self-assembling polymerization of a boric acid-melamine-formaldehyde (MF) colloid. It is found that ammonia-annealing of an air-pyrolysis (700 °C) intermediate causes higher BN phase transformation within final BN microspheres with more uniform diameter distribution compared to those of direct ammonia-pyrolysis of spherical precursors at the same temperatures of 1100 and 1500 °C. After ammonia-annealing and ammonia-pyrolyzed treatment at 1100 and 1500 °C, the obtained BN microspheres have a low specific surface area (SSA) property, but replacing part of melamine with dicyandiamide could increase their SSAs to more than 1000 m2/g. We believe that this new microspherical BN preparation with more facile and controllable operation would be well suited for industrialization.

Boron nitride nanosheets wrapped by reduced graphene oxide for promoting polysulfides adsorption in lithium-sulfur batteries.

The polysulfides shuttling and slow redox kinetics of sulfur-based cathodes have severely hindered the commercialization of lithium-sulfur (Li-S) batteries. Herein, distinctive three-dimensional microspheres composed of boron nitride (BN) nanosheets and reduced graphene oxide (rGO) were applied to act as efficient sulfur cathode hosts for the first time using in a spray-drying process. Using this construction, the robust microsphere structure could shorten ion diffusion pathways and supply sufficient spaces to alleviate the volumetric expansion of sulfur during lithiation. Besides, the synergistic effect between BN and rGO significantly enhanced polysulfides adsorption capability and accelerated their conversion, verified by the density functional theory (DFT) calculations and adsorption experiments. Consequently, the S-BN@rGO cathode could manifest the high initial capacity (1137 mAh g-1 at 0.2 C) and remarkable cycling/stability performance (572 mAh g-1 at 1 C after 500 cycles). These results shed light on a design concept of high-performance sulfur cathode host materials.

Enhanced Performance of Li-S Batteries due to Synergistic Adsorption and Catalysis Activity within a Separation Coating Made of Hybridized BNNSs/N-Doping Porous Carbon Fibers.

Lithium-sulfur (Li-S) batteries with high theoretical energy density are considered as the most promising devices for rechargeable energy-storage systems. However, their actual applications are rather limited by the shuttle effect of lithium polysulfides (LiPSs) and the sluggish redox kinetics. Here, the boron nitride nanosheets are homodispersedly embedded into N-doping porous carbon fibers (BNNSs/CHFs) by an electrospinning technique and a subsequent in situ pyrolysis process. The hybridized BNNSs/CHFs can be smartly designed as a multifunctional separation coating onto the commercial PP membrane to enhance the electrochemical performance of Li-S batteries. As a result, the Li-S batteries with extra BNNSs/CHF modification deliver a highly reversible discharge capacity of 830.4 mA h g-1 at a current density of 1 C. Even under 4 C, the discharge specific capacity can reach up to 609.9 mA h g-1 and maintain at 553.9 mA h g-1 after 500 cycles, showing a low capacity decay of 0.01836% per cycle. It is considered that the excellent performance is attributed to the synergistic effect of adsorption and catalysis of the BNNSs/CHF coating used. First, this coating can efficiently reduce the charge transfer resistance and enhance Li-ion diffusion, due to increased catalytic activity from strong electronic interactions between BNNSs and N-doping CHFs. Second, the combination of polar BNNSs and abundant pore structures within the hybridized BNNSs/CHF networks can highly facilitate an adsorption for LiPSs. Here, we believed that this work would provide a promising strategy to increase the Li-S batteries' performance by introducing hybridized BNNSs/N-doping carbon networks, which could efficiently suppress the LiPSs' shuttle effect and improve the electrochemical kinetics of Li-S batteries.

Highly Multifunctional and Thermoconductive Performances of Densely Filled Boron Nitride Nanosheets/Epoxy Resin Bulk Composites.

In the development of hexagonal boron nitride (h-BN)-based polymeric composites with high thermal conductivity, it is always challenging to achieve a dense filling of h-BN fillers to form a desired high-density thermal transfer network. Here, a series of boron nitride nanosheets (BNNSs)/epoxy resin (EP) bulk composites filled with ultrahigh BNNSs content (65-95 wt %) is successfully constructed through a well-designed mechanical-balling prereaction combined with a general pressure molding method. By means of this method, the highly filled BNNSs fillers are uniformly dispersed and strongly bonded with EP within the composites. As a result, the densely BNNSs-filled composites can exhibit multiple performances. They have excellent mechanical properties, and their maximum compression strength is 30-97 MPa. For a BNNSs/EP composite with filling ultrahigh BNNSs fraction up to 90 wt %, its highly in-plane thermal conductivities (TC) are 6.7 ± 0.1 W m-1 K-1 (at 25 °C) to 8.7 ± 0.2 W m-1 K-1 (200 °C), respectively. In addition, the minimum coefficient of thermal expansion of BNNSs/EP composites is 4.5 ± 1.3 ppm/°C (only ∼4% of that of the neat EP), while their dielectric constants are basically located between 3-4 along with their dielectric loss tangent values exceptionally <0.3 in the ultrahigh frequency range of 12-40 GHz. Additionally, these BNNSs/EP composites exhibit remarkable cycle stability in heat transfer during heating and cooling processes because of their structural robustness. Thus, this type of densely BNNSs-filled BNNSs/EP composite would have great potential for further practical thermal management fields.

Heterostructured Electrocatalysts for Hydrogen Evolution Reaction Under Alkaline Conditions.

The hydrogen evolution reaction (HER) is a half-cell reaction in water electrolysis for producing hydrogen gas. In industrial water electrolysis, the HER is often conducted in alkaline media to achieve higher stability of the electrode materials. However, the kinetics of the HER in alkaline medium is slow relative to that in acid because of the low concentration of protons in the former. Under the latter conditions, the entire HER process will require additional effort to obtain protons by water dissociation near or on the catalyst surface. Heterostructured catalysts, with fascinating synergistic effects derived from their heterogeneous interfaces, can provide multiple functional sites for the overall reaction process. At present, the activity of the most active known heterostructured catalysts surpasses (platinum-based heterostructures) or approaches (noble-metal-free heterostructures) that of the commercial Pt/C catalyst under alkaline conditions, demonstrating an infusive potential to break through the bottlenecks. This review summarizes the most representative and recent heterostructured HER catalysts for alkaline medium. The basics and principles of the HER under alkaline conditions are first introduced, followed by a discussion of the latest advances in heterostructured catalysts with/without noble-metal-based heterostructures. Special focus is placed on approaches for enhancing the reaction rate by accelerating the Volmer step. This review aims to provide an overview of the current developments in alkaline HER catalysts, as well as the design principles for the future development of heterostructured nano- or micro-sized electrocatalysts.