Mesoporous Hollow Research Articles

Efficient Co-Delivery of Metformin and Ammonia Borane via a Hollow Mesoporous Polydopamine Nanogenerator for Enhanced Chemo-Photothermal Therapy against Melanoma.

Melanoma, a highly aggressive skin cancer, poses significant challenges due to its rapid metastases and high mortality rates. While metformin (Met), a first-line medication for type 2 diabetes, has shown promise in inhibiting tumor growth and metastases, its clinical efficacy in cancer therapy is limited by low bioavailability, short half-life, and gastrointestinal adverse reactions associated with oral administration. In this study, we developed a hollow mesoporous polydopamine nanocomposite (HMPDA-PEG@Met@AB) coloaded with Met and ammonia borane (AB), designed to enable a combined gas-assisted, photothermal, and chemotherapeutic approach for melanoma treatment. This system releases Met and H2 in response to the acidic tumor microenvironment both in vitro and in vivo. The released H2 facilitates nanocomposites escape from lysosomes and inhibits heat shock protein expression in B16-F10 cells. Concurrently, Met and H2 disrupt the mitochondrial respiratory chain, reduce mitochondrial membrane potential, and inhibit ATP synthesis, ultimately activating AMPK signaling and suppressing mTOR activity. The system also elevates reactive oxygen species (ROS) levels, leading to tumor cell apoptosis. Under 808 nm near-infrared irradiation, the photothermal effect of HMPDA enhances Met release, further inhibiting tumor growth. In vivo experiments demonstrated efficient Met delivery, achieving therapeutic levels that activated AMPK in tumors without inducing hypoglycemia. These findings suggest that this drug delivery system holds significant clinical potential for melanoma treatment.

Oral Akkermansia muciniphila Biomimetic Nanotherapeutics for Ulcerative Colitis Targeted Treatment by Repairing Intestinal Epithelial Barrier and Restoring Redox Homeostasis.

The structural disruption of intestinal barrier and excessive reactive oxygen/nitrogen species (RONS) generation are two intertwined factors that drive the occurrence and development of ulcerative colitis (UC). Synchronously restoring the intestinal barrier and mitigating excess RONS is a promising strategy for UC management, but its treatment outcomes are still hindered by low drug accumulation and retention in colonic lesions. Inspired by intestine colonizing bacterium, we developed a mucoadhesive probiotic Akkermansia muciniphila-mimic entinostat-loaded hollow mesopores prussian blue (HMPB) nanotherapeutic (AM@HMPB@E) for UC-targeted therapy via repairing intestinal barrier and scavenging RONS. After oral administration, the negatively charged AM@HMPB@E specifically bind to the positively charged inflamed colon lesions via electrostatic interactions and Akkermansia muciniphila membrane-mediated bioadhesion mechanism. Subsequently, the superoxide dismutase (SOD)-, and catalase (CAT)-like HMPB eliminated RONS, thereby alleviating RONS-mediated inflammation and intestinal epithelial damage. Meanwhile, the UC-site locally released entinostat could repair the damaged intestinal epithelial barrier by inhibiting intestinal endothelial cell apoptosis and up-regulating the expression of tight junctions. Both in vitro and in vivo results shown that AM@HMPB@E not only exhibited an exceptional retention in the colitis site but also demonstrated superior therapeutic efficacy compared to the first-line drug sulfasalazine, as evidenced by the longer colon, less rectal bleeding and body weight loss. Collectively, our findings highlight the clinical application prospects of this synchronous nanotherapeutic strategy for UC treatment, offering a paradigm for the rational design of oral nanomedicine.

Preparation of Hollow Mesoporous Silica Microspheres Using Polystyrene Microspheres as Templates

Preparation of Hollow Mesoporous Silica Microspheres Using Polystyrene Microspheres as Templates

Heterogeneous Double-layer Mesoporous Hollow Spheres SnSe2@N, Se-C as Anode for Enhanced Energy Storage Performance of Lithium/Sodium Ion Batteries

Heterogeneous Double-layer Mesoporous Hollow Spheres SnSe2@N, Se-C as Anode for Enhanced Energy Storage Performance of Lithium/Sodium Ion Batteries

Enhanced Photothermal/Immunotherapy under NIR Irradiation Based on Hollow Mesoporous Responsive Nanomotor.

In this research, a hollow mesoporous responsive nanomotor was proposed for enhanced photothermal/immunotherapy under near infrared (NIR) irradiation. HA-HMCuS/AS as the nanomotor composed of hollow mesoporous copper sulfide (HMCuS) loaded with artesunate (AS) and hyaluronic acid (HA) was utilized to induce the polarization of tumor-associated macrophages. At the beginning, ResNet18 deep learning model was utilized to predict the Brunauer-Emmett-Teller (BET) surface area of HMCuS based on the morphology data set which was obtained from our conventional research. And then, we predicted that the as-synthesized HMCuS has a large surface area, which is beneficial for drug loading. Then, upon near-infrared light irradiation, HA-HMCuS/AS exhibited significant cytotoxicity against breast cancer cells and induced tumor thermal ablation. Additionally, HA-HMCuS/AS was found to inhibit the expression of TREM2 at the tumor site, promoting the transition of M2-type macrophages to M1-type macrophages in tumor tissue and enhancing the inflammatory response at the tumor site. In addition, photothermal therapy enabled tumor cells to release tumor-associated antigen and injury-related molecular patterns, promote the maturation and metastasis of dendritic cells, and further activate the body's specific antitumor immune response. By combining photothermal therapy with immunotherapy, the HA-HMCuS nanomotor demonstrated even more robust tumor ablation and suppression effects.

Pt2Gd Alloy Nanoparticles from Organometallic Pt and Gd Complexes and Hollow Mesoporous Carbon Spheres: Enhanced Oxygen Reduction Reaction Activity and Durability.

Pt2Gd alloy nanoparticles supported in hollow mesoporous carbon spheres (HMCS; Pt2Gd/HMCS) were successfully prepared by the thermal reduction of organometallic Pt and Gd complexes without oxygen atoms supported in the pores of HMCS. The structures of Pt2Gd alloy nanoparticles were fully characterized by TEM, HAADF-STEM-EDS, XRD, XAFS, and XPS, suggesting the formation of uniform Pt2Gd alloy nanoparticles with an average particle size of 5.9 nm. Pt2Gd/HMCS showed superior oxygen reduction reaction activity (2.4 times higher mass-specific activity to Pt nanoparticles on HMCS (Pt/HMCS)) and remarkable durability even after the 100,000 cycles of accelerated degradation tests compared to Pt/HMCS and a commercial Pt/C catalyst. The structure of the Pt2Gd alloy nanoparticles after initial aging and the durability tests suggested that the Pt2Gd core-Pt shell structure with a particle size similar to the pore size of HMCS was stably formed inside the porous structure of HMCS and maintained under the oxygen-reduction working conditions.

Nitric Oxide-Releasing Mesoporous Hollow Cerium Oxide Nanozyme-Based Hydrogel Synergizes with Neural Stem Cell for Spinal Cord Injury Repair.

Neural stem cell (NSCs) transplantation is a promising therapeutic strategy for spinal cord injury (SCI), but its efficacy is greatly limited by the local inhibitory microenvironment. In this study, based on l-arginine (l-Arg)-loaded mesoporous hollow cerium oxide (AhCeO2) nanospheres, we constructed an injectable composite hydrogel (AhCeO2-Gel) with microenvironment modulation capability. AhCeO2-Gel protected NSCs from oxidative damage by eliminating excess reactive oxygen species while continuously delivering Nitric Oxide to the lesion of SCI in a pathological microenvironment, the latter of which effectively promoted the neural differentiation of NSCs. The process was confirmed to be closely related to the up-regulation of the cAMP-PKA pathway after NO-induced calcium ion influx. In addition, AhCeO2-Gel significantly promoted the polarization of microglia toward the M2 subtype as well as enhanced the regeneration of spinal nerves and myelinated axons. The prepared bioactive hydrogel system also efficiently facilitated the integration of transplanted NSCs with host neural circuits, replenished damaged neurons, alleviated neuroinflammation, and inhibited glial scar formation, thus significantly accelerating the recovery of motor function in SCI rats. Therefore, AhCeO2-Gel synergized with NSCs transplantation has great potential as an integrated therapeutic strategy to treat SCI by comprehensively reversing the inhibitory microenvironment.

Cobalt nanoparticles decorated hollow N-doped carbon nanospindles enable high-performance lithium-oxygen batteries.

Despite the ultrahigh theoretical energy density and cost-effectiveness, aprotic lithium-oxygen (Li-O2) batteries suffer from slow oxygen redox kinetics at cathodes and large voltage hysteresis. Here, we well-design ultrafine Co nanoparticles supported by N-doped mesoporous hollow carbon nanospindles (Co@HCNs) to serve as efficient electrocatalysts for Li-O2 battery. Benefiting from strong metal-support interactions, the obtained Co@HCNs manifest high affinity for the LiO2 intermediate, promoting formation of ultrathin nanosheet-like Li2O2 with low-impedance contact interface on the Co@HCNs cathode surface, which facilitates the reversible decomposition upon charging. The mesoporous hollow nanospindles can provide abundant electron/ions transport channels to synergistically accelerate the formation and decomposition of discharge products. The Li-O2 battery based on Co@HCNs displays remarkably reduced discharge/charge polarization of 0.92V, impressive rate performance, and stable operation for 250 cycles. This work will provide a new avenue to design advanced oxygen electrocatalysts for high-performance Li-O2 battery.

Nanotechnology-Driven Delivery of Caffeine Using Ultradeformable Liposomes-Coated Hollow Mesoporous Silica Nanoparticles for Enhanced Follicular Delivery and Treatment of Androgenetic Alopecia.

Androgenetic alopecia (AGA) is caused by the impact of dihydrotestosterone (DHT) on hair follicles, leading to progressive hair loss in men and women. In this study, we developed caffeine-loaded hollow mesoporous silica nanoparticles coated with ultradeformable liposomes (ULp-Caf@HMSNs) to enhance caffeine delivery to hair follicles. Caffeine, known to inhibit DHT formation, faces challenges in skin penetration due to its hydrophilic nature. We investigated caffeine encapsulated in liposomes, hollow mesoporous silica nanoparticles (HMSNs), and ultradeformable liposome-coated HMSNs to optimize drug delivery and release. For ultradeformable liposomes (ULs), the amount of polysorbate 20 and polysorbate 80 was varied. TEM images confirmed the mesoporous shell and hollow core structure of HMSNs, with a shell thickness of 25-35 nm and a hollow space of 80-100 nm. SEM and TEM analysis showed particle sizes ranging from 140-160 nm. Thermal stability tests showed that HMSNs coated with ULs exhibited a Td10 value of 325 °C and 70% residue ash, indicating good thermal stability. Caffeine release experiments indicated that the highest release occurred in caffeine-loaded HMSNs without a liposome coating. In contrast, systems incorporating ULp-Caf@HMSNs exhibited slower release rates, attributable to the dual encapsulation mechanism. Confocal laser scanning microscopy revealed that ULs-coated particles penetrated deeper into the skin than non-liposome particles. MTT assays confirmed the non-cytotoxicity of all HMSN concentrations to human follicle dermal papilla cells (HFDPCs). ULp-Caf@HMSNs promoted better cell viability than pure caffeine or caffeine-loaded HMSNs, highlighting enhanced biocompatibility without increased toxicity. Additionally, ULp-Caf@HMSNs effectively reduced ROS levels in DHT-damaged HFDPCs, suggesting they are promising alternatives to minoxidil for promoting hair follicle growth and reducing hair loss without increasing oxidative stress. This system shows promise for treating AGA.

Gelation embolism agents suppress clinical TACE-incited pro-metastatic microenvironment against hepatocellular carcinoma progression

Current embolic agents in transcatheter arterial chemoembolization (TACE) of hepatocellular carcinoma (HCC) encounter instability and easy leakage, discounting TACE efficacy with residual HCC. Moreover, clinical TACE aggravates hypoxia and pro-metastatic microenvironments, rendering patients with HCC poor prognosis. Herein, we developed Zein-based embolic agents that harness water-insoluble but ethanol-soluble Zein to encompass doxorubicin (DOX)-loaded mesoporous hollow MnO2 (HMnO2). The conditions and capacity of HMnO2 to generate reactive oxygen species (ROS) were assayed. Mechanical examinations of Zein-HMnO2@DOX were performed to evaluate its potential as the embolic agent. Invitro experiments were carried out to evaluate the effect of Zein-HMnO2@DOX on HCC. The subcutaneous HCC mouse model and rabbit VX2 HCC model were established to investigate its anti-tumor and anti-metastasis efficacy and explore its potential anti-tumor mechanism. The high adhesion and crosslinking of Zein with HMnO2@DOX impart Zein-HMnO2@DOX with strong mechanical strength to resist deformation and wash-off. Zein gelation and HMnO2 decomposition in response to water and acidic tumor microenvironment, respectively, enable continuous DOX release and Fenton-like reaction for reactive oxygen species (ROS) production and O2 release to execute ROS-enhanced TACE. Consequently, Zein-based embolic agents outperform clinically-used lipiodol to significantly inhibit orthotopic HCC growth. More significantly, O2 release down-regulates hypoxia inducible factor (HIF-1α), vascular endothelial growth factor (VEGF) and glucose transporter protein 1 (GLUT1), which thereby re-programmes TACE-aggravated hypoxic and pro-metastatic microenvironments to repress HCC metastasis towards lung. Mechanistic explorations uncover that such Zein-based TACE agents disrupt oxidative stress, angiogenesis and glycometabolism pathways to inhibit HCC progression. This innovative work not only provides a new TACE agent for HCC, but also establishes a new strategy to ameliorate TACE-aggravated hypoxia and metastasis motivation against clinically-common HCC metastasis after TACE operation. Excellent Young Science Fund for National Natural Science Foundation of China (82022033); National Natural Science Foundation of China (Grant No. 82373086, 82102761); Major scientific and technological innovation project of Wenzhou Science and Technology Bureau (Grant No. ZY2021009); Shanghai Young Top-Notch Talent.

Confining Pt Nanoparticles in Layered Double Hydroxide Derived Hollow Mesoporous MgAl‐Oxide Nanospheres for Boosting Selective Transfer Hydrogenation

AbstractCatalytic transfer hydrogenation (CTH) is a safe and effective strategy for producing unsaturated alcohols (UOLs) from biomass‐derived α,β‐unsaturated aldehydes/ketones. Accordingly, the design of CTH catalysts that possess both extreme activity and superior selectivity is highly desirable. Herein, we develop a highly efficient Pt@hMgAl catalyst with Pt nanoparticles (NPs) confined in the layered double hydroxide derived hollow MgAl‐oxide nanospheres (hMgAl), which shows an enhanced catalytic performance in CTH of furfural (FFR) to furfuryl alcohol (FOL) compared to the hMgAl catalyst without Pt NPs inside. It is found that the reaction rate over the Pt@hMgAl (12.8 mmol gcat−1 h−1) is ~26 times higher than that over the hMgAl (0.5 mmol gcat−1 h−1). The excellent catalytic performance of Pt@hMgAl originates from the synergy between Pt‐(Mg−O−Al) interfacial sites, where the acid‐base site of Mg−O−Al activates the C=O bond of FFR, while the nearby Pt site facilitates the dehydrogenation of 2‐propanol. Moreover, the reaction rate over the Pt@hMgAl can further increase to 21.8 mmol gcat−1 h−1 after introducing H2 into the reaction system, where the FOL selectivity is still higher than 99 % due to the synergy of Pt‐(Mg−O−Al) interfacial sites. This work provides a straightforward approach to construct a hollow‐structured catalyst with abundant metal/oxide interfaces, which could significantly enhance the CTH efficiency for α,β‐unsaturated alcohols production.

Improved Energy Storage Performance of N-Doped Hollow Mesoporous Carbon Spheres as Substrate for MoS2

Improved Energy Storage Performance of N-Doped Hollow Mesoporous Carbon Spheres as Substrate for MoS2

Oxidation of Toluene over the Pt-Embedded Mesoporous CeO2 Hollow Nanospheres with Advanced Catalytic Performances.

In this study, the novel Pt-embedded mesoporous CeO2 hollow nanospheres (Pt-MS-CeO2-H) with varying Pt contents (0.5-3.0 wt %) were facilely prepared. The Pt nanoparticles were one-pot embedded within the mesoporous shell of Pt-MS-CeO2-H and assisted with the reduction Ostwald ripening process. The traditional preparation methods often face challenges, such as the uneven distribution or aggregation of nanoparticles, as well as difficulty in maintaining high catalytic activity at low Pt content. Compared with the traditional supported Pt/MS-CeO2 catalyst, the embedding strategy facilitated precise control over the position, distribution, and uniformity of Pt nanoparticles within the CeO2 mesoporous shell. Additionally, the encapsulation process of Pt nanoparticles played a pivotal role in generating oxygen vacancies and activating surface chemical adsorption of oxygen. Resultantly, the toluene oxidation performances of 1Pt-MS-CeO2-H catalyst showed much lower T90 (171 °C) than 1Pt/MS-CeO2 (311 °C). To elucidate the underlying reasons, in situ diffuse reflectance infrared Fourier transform spectroscopy of toluene oxidation was employed to identify the reaction intermediates and pathways over these catalysts. In summary, the Pt-embedded mesoporous CeO2 hollow nanosphere catalysts were considered as potential candidates when designing high-performance toluene catalytic oxidation catalysts.

Modification of polypropylene separator with multifunctional layers to achieve highly stable sodium metal anode

Separator modification is an effective approach to suppress dendrite growth to realize high-energy sodium metal batteries (SMBs) in practical applications, however, its success is mainly subject to surface modification. Herein, a separator with multifunctional layers composed of N-doped mesoporous hollow carbon spheres (HCS) as the inner layer and sodium fluoride (NaF) as the outer layer on commercial polypropylene separator (PP) is proposed (PP@HCS-NaF) to achieve stable cycling in SMB. At the molecular level, the inner HCS layer with a high content of pyrrolic-N induces the uniform Na+ flux as a potential Na+ redistributor for homogenous deposition, whereas its hollow mesoporous structure offers nano-porous buffers and ion channels to regulate Na+ ion distribution and uniform deposition. The outer layer (NaF) constructs the NaF-enriched robust solid electrolyte interphase layer, significantly lowering the Na+ ions diffusion barrier. Benefiting from these merits, higher electrochemical performances are achieved with multifunctional double-layered PP@HCS-NaF separators compared with single-layered separators (i.e. PP@HCS or PP@NaF) in SMBs. The Na||Cu half-cell with PP@HCS-NaF offers stable cycling (280 cycles) with a high CE (99.6%), and Na||Na symmetric cells demonstrate extended lifespans for over 6000 h at 1 mA cm−2 with a progressively stable overpotential of 9 mV. Remarkably, in Na||NVP full-cells, the PP@HCS-NaF separator grants a stable capacity of ∼81 mA h g−1 after 3500 cycles at 1 C and an impressive rate capability performance (∼70 mA h g−1 at 15 C).

Pt-Ru atomic alloys confined in mesoporous carbon hollow spheres for accelerating methanol oxidation

Active and durable electrocatalysts are essential for commercializing direct methanol fuel cells. However, Pt-based catalysts, extensively utilized in the methanol oxidation reaction (MOR), are suffered from resource scarcity and CO poisoning, which degrade MOR activity severely. Herein, Pt1Rux bimetallic catalysts were synthesized by confining Pt1Rux alloys within the shells of mesoporous carbon hollow spheres (MCHS) via a vacuum-assisted impregnation method (Pt1Rux@MCHS). The confinement effect induced by mesoporous carbon hollow spheres resulted in a robust structure of Pt1Ru3@MCHS with an ultrafine dispersion of alloy nanoparticles. The experimental and theoretical results confirmed that the boosting electrocatalytic activity and stability of the MOR over Pt1Ru3@MCHS were contributed to the regulated electronic structure as well as the superior CO tolerance of atomic Pt site caused by the electronic interaction between single Pt atoms and Ru nanoparticles. This strategy is versatile for the rational design of Pt-based bimetallic catalysts and has a positive impact on MOR performance.

Mesoporous carbon hollow spheres based sensitive SPME probes for in vivo sampling analysis of selected plant hormones in Chinese aloes

Phytohormones are a class of endogenous substances that separately or synergistically regulate the growth, development, and differentiation of plants. Accurately and efficiently detecting and monitoring the concentration of plant hormones in living plants is of significant importance. Herein, a novel mesoporous carbon hollow spheres (MCHS)-based in vivo solid phase microextraction (SPME) probe was designed for in vivo sampling of plant hormones. The designed MCHS features the advantages of high surface area, porous shells, and large hollow spaces, facilitating the dynamic adsorption and enrichment of target phytohormone. In addition, a cationic polyelectrolyte, (poly (diallyl dimethyl ammonium chloride) (PDDA), was further modified onto the MCHS to expedite the extraction process by electrostatic interaction. Utilizing the MCHS@PDDA probe in combination with HPLC-MS/MS facilitated the continuous monitoring of three plant hormones (abscisic acid (ABA), indole-3-acetic acid (IAA), and gibberellin (GA3)) in Chinese aloe. The detection limit of this method was 0.016–0.090 μg/L, the linear range was 10–1000 μg/L, and both the RSD of the single probe (n = 6) and probe-to-probe test (n = 6) were less than 7.2 %. This method had excellent accuracy and good reproducibility comparable to the traditional sample pretreatment method. Ultimately, this established in-vivo SPME method was successfully adopted to quantify three selected plant hormones in living Chinese Aloes, providing a new method for the long-term monitoring of endogenous active substances in living system.

Mesoporous Hollow Carbon Sphere-Embedded MXene Architectures Decorated with Ultrafine Rh Nanocrystals toward Methanol Electrooxidation.

The development of advanced Pt-alternative anode electrocatalysts with high activity and reliable stability is critical to overcoming the technical challenges of direct methanol fuel cells. Here, we propose a robust bottom-up strategy for the spatial construction of mesoporous hollow carbon sphere (HCS)-embedded MXene architectures decorated with ultrafine Rh nanocrystals (Rh/HCS-MX) via stereoscopic coassembly reactions. The rational intercalation of HCS effectively separates the MXene nanowalls to achieve a rapid mass-transfer efficiency, while the intimate coupling of the hybrid carrier with Rh nanocrystals enables their electronic structure optimization, thus contributing to strong synergistic catalytic effects. Accordingly, the resulting Rh/HCS-MX architectures exhibit outstanding methanol electrooxidation properties in terms of large electrochemical active surface areas, high mass/specific activities, and good long-term stability, all of which are significantly superior to the traditional Rh/carbon black, Rh/HCS, and Rh/MXene as well as commercial Pt/carbon balck and Pd/carbon balck electrocatalysts.

Adsorption of dinotefuran using TpBDMe COF nanoparticles for soil leaching reduction and bee safety

Dinotefuran (DIN) contaminates groundwater and is toxic to bees, so designing a novel pesticide loading system for dinotefuran is of great significance. In this paper, dinotefuran was loaded into TpBDMe COF with a mesoporous hollow structure, and the TpBDMe COF loaded with dinotefuran exhibited initial burst and subsequent sustained release behavior. The results showed that the product effectively suppresses wheat aphid development, with virtually no infestation occurring for 7–14 days, whereas other commercially available formulation had lost their usefulness. Our TpBDMe COF carrier effectively immobilizes dinotefuran, reducing pesticide leaching in soil by 70 % and enhancing the application efficiency of neonicotinoid insecticides. The LD50 of this product for acute exposure of honey bees doubled the LD50 of the original furosemide at 24 h and was equally effective at 48 h, reducing the toxicity to bees and promoting ecological safety. The results of this work show that this nanocarrier system is highly stable, loadable, insecticidal active, and environmentally friendly, showing great potential in the development of new nanocarriers for use.

Accelerated Fe2+ regeneration for efficient electro-Fenton oxidation of refractory pollutants through pore structure engineering

Electro-Fenton (EF) is efficient in decontaminating refractory pollutants but high consumption of Fe2+ as a hydrogen peroxide (H2O2) activator increases its operation cost. Designing EF system with accelerated Fe2+/Fe3+ cycling is crucial for both hydroxyl radical generation and Fe2+ dosage reduction. Here, we employed pore structure tailoring engineering to optimize pore size of mesoporous hollow carbon spheres (MHCS), achieving an improved H2O2 electro-synthesis and Fe2+ regeneration. MHCS with 8 nm surface pores yielded 81.33 mmol gcatalyst−1h−1 H2O2 and realized 51.2 % Fe2+ regeneration efficiency, enabling complete removal of sulfamethazine with a low energy consumption of just 0.87 kWh g−1 total organic carbon. Finite element simulation revealed that MHCS with 8 nm surface pores favored mass transfer, facilitating solute diffusion to the electrode’s active layer for reaction. In addition, EF system maintained a degradation efficiency of 90 % after five cycles of operation and was effective in removing various types of pollutants, which implies its application potential. This work demonstrated a novel catalyst structure optimization strategy to both enhance Fe2+ regeneration and improve EF performance, offering an energy-efficient water purification solution.

Electronic regulation of hcp-Ru by d-d orbital coupling for robust electrocatalytic hydrogen oxidation in alkaline electrolytes

Bimetallic alloys hold exceptional promise as candidate materials because they offer a diverse parameter space for optimizing electronic structures and catalytic sites. Herein, we fabricate ruthenium-cobalt alloy nanoparticles uniformly dispersed within hollow mesoporous carbon spheres (hcp-RuCo@C) via impregnation and pyrolysis strategies. The intriguing hollow mesopore structure of hcp-RuCo@C facilitates efficient contact between active sites and reactants, thereby accelerating hydrogen oxidation reaction (HOR) kinetics. As anticipated, the hcp-RuCo@C showcases remarkable exchange current density and mass activity of 3.73 mA cm−2 and 2.8 mA μgRu-1, respectively, surpassing those of commercial Pt/C and documented Ru-based electrocatalysts. Notably, hcp-RuCo@C demonstrates robust resistance to 1000 ppm CO, a trait lacking in Pt/C catalysts. Comprehensive experimental results reveal that the alloying-induced d-d electronic interactions between Ru and Co species significantly optimizes hydrogen binding energy (HBE) and hydroxide binding energy (OHBE). This optimization promotes the vital Volmer step, ameliorating the alkaline HOR properties of hcp-RuCo@C.