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[Display omitted] • A/R-TiO 2 -Ag 3 PO 4 photocatalyst was prepared by depositing Ag 3 PO 4 on the surface of anatase/rutile TiO 2 hollow spheres. • A/R-TiO 2 -Ag 3 PO 4 exhibited more efficient than A-TiO 2 -Ag 3 PO 4 and P25-Ag 3 PO 4 photocatalysts in pesticides degradation. • The combination of hollow structure and dual-heterojunction was the key parameter in promoting efficient photocatalytic performance. • Dual-pathway charge transfer mechanism suppresses the recombination of photogenerated charge pairs. • The photodegradation pathways and mechanism of pesticide were detailed. Exploring high-performance photocatalysts still remains a big challenge due to poor charge separation efficiency. Herein, we prepare a novel anatase/rutile TiO 2 -Ag 3 PO 4 hollow photocatalyst (A/R-TiO 2 -Ag 3 PO 4) for addressing this challenge. Microstructural characterization and photoelectric measurements confirm that the synergy of hollow structure and dual-heterojunction can provide abundant active sites and boost efficient charge separation through dual-pathway charge transfer mechanism. The A/R-TiO 2 -Ag 3 PO 4 photocatalyst exhibits the highest photocurrent density (15.25 µA cm−2), which is 8.4 and 5.2 times than that of A-TiO 2 -Ag 3 PO 4 (1.82 µA cm−2) and P25-Ag 3 PO 4 (2.93 µA cm−2), respectively. Photo-degradation experiment shows that A/R-TiO 2 -Ag 3 PO 4 presents a high degradation percentage (98.7 %) of thiamethoxam (THX) within 30 min, which is 1.45 and 1.23 times than that of A-TiO 2 -Ag 3 PO 4 (68.1 %) and P25-Ag 3 PO 4 (80.7 %), respectively. Furthermore, the degradation percentage of THX by A/R-TiO 2 -Ag 3 PO 4 is as high as 96.4 % after seven successive cycles, indicating excellent cycling stability. Therefore, this work provides a new insight into exploring other high-performance photocatalysts by combining hollow structure and dual-heterojunction. [ABSTRACT FROM AUTHOR]

A novel hollow ZIF-8/CdS heterojunction photocatalyst was synthesized to catalyze the cleavage of the C β -O bond of lignin β-O-4 model compounds, and the cleavage rate reached 30.3 ∙mmol∙h−1∙g−1 within 20 min. [Display omitted] Photocatalytic splitting of the C β -O bond is regarded as a prospective strategy for transforming lignin, and it is imperative to develop novel photocatalysts with effective photogenerated charges separation and solar absorption capacity. Herein, a novel hollow ZIF-8/CdS heterostructure photocatalyst was synthesized for the catalytic splitting of lignin C β -O bonds. The photocatalytic cleavage rate of C β -O bond of ligin β-O-4 reached 30.3∙mmol∙h−1∙g−1 within 20 min under visible light exposure. It is noteworthy that the utilization of intricate natural lignin molecules in this photocatalytic system has yielded successful depolymerization. The DFT and XPS results indicate a potential unidirectional electron migration from ZIF-8 to CdS in ZIF-8/CdS composites transfer. This electron transport path follows the direct Z-scheme heterostructure mechanism, resulting in the generation of an internal electric field between ZIF-8 and CdS. Impressively, the synergistic combination of the hollow structure and Z-scheme heterostructure effectively enhances the efficiency of charge carrier separation and maintains a robust redox potential, thereby facilitating C α -radical generation. This study proposes a novel photocatalyst design strategy that integrates hollow structures and Z-scheme heterojunctions, with the aim of targeting the depolymerization of the C β -O bond in lignin. [ABSTRACT FROM AUTHOR]

Cisplatin (CDDP) combined with pemetrexed (MTA) is commonly employed in the treatment of advanced non‐small cell lung cancer. However, conventional clinical administration methods fail to achieve precise spatiotemporal delivery within the tumor microenvironment (TME), resulting in inadequate control of local drug concentrations and impeding the synergistic efficacy of chemotherapeutic drugs. Aiming to address this issue, Fe2O3 hollow multi‐shelled structure (HoMS) nanocarriers with spatiotemporally controlled release properties and co‐encapsulated CDDP and MTA into this nanocarrier are developed. The confined microenvironment provided by Fe2O3‐HoMS enables a targeted and temporal sequential drug release tailored to clinical requirements. Furthermore, chemotherapy‐induced DNA damage leads to apoptosis, accompanied by a substantial generation of reactive oxygen species (ROS). The disruption of ROS homeostasis subsequently activates the ferroptosis pathway mediated by Fe2O3‐HoMS. In summary, Fe2O3‐HoMS exhibits a highly controlled and temporal sequential release of two chemotherapeutic drugs in TME, and the HoMS nanocarriers are further involved in the regulation of ferroptosis, realizing a triple sequential delivery system comprising CDDP‐MTA‐Fe2+ and thus significantly enhancing the anti‐tumor efficacy against lung cancer. This study proposes a novel approach for temporal sequential drug delivery by optimizing nanocarrier design, addressing the clinical challenge of precisely controlled drug release within tumors. [ABSTRACT FROM AUTHOR]

[Display omitted] The efficiency of photocatalytic hydrogen evolution can be significantly enhanced while maintaining cost-effectiveness through the synergistic effect of defect surface engineering and multi-component heterojunctions. The structure and properties of NiCo 2 O 4 nanorods were modified by inducing oxygen vacancies at different temperatures in this study, resulting in improved optical properties and electron adsorption capacity. The presence of oxygen vacancies leads to a reduction in the band gap of NiCo 2 O 4 , thereby enhancing electron transport efficiency through band gap engineering. Simultaneously, surface properties undergo changes, and vacancy defects serve as electron trapping centers, facilitating an increased participation of electrons in the hydrogen evolution reaction process. The dodecahedron KMP with a cavity structure is additionally introduced to form an S-scheme heterojunction with NiCo 2 O 4. This establishes a novel mechanism for electron transport, which effectively enhances the separation of electron-hole pairs and improves the redox capacity of the photocatalytic system. The adsorption of intermediates in the hydrogen production process is enhanced through synergistic regulation of d-band centers via surface defect engineering and S-scheme heterojunction. Additionally, this approach improves the separation efficiency of electron-hole pairs and accelerates electron transfer dynamics, significantly enhancing hydrogen production efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] • A unique carbon coating Ge nanospheres with a cubic hollow structure (Ge@C) is controllably designed and synthesized by using low-cost GeO 2 as precursor. • The hollow Ge@C nanostructure not only provides abundant internal space to alleviate volumetric expansion of Ge, but also facilitates the transmission of Li+ and electrons. • The hollow Ge@C shows very superior lithium storage performance with enhanced Li+ adsorption ability and low Li+ diffusion energy barrier. • This work is a very important breakthrough for the development of high-performance Ge based anode for lithium ion batteries. Germanium based nanomaterials are very promising as the anodes for the lithium ion batteries since their large specific capacity, excellent lithium diffusivity and high conductivity. However, their controllable preparation is still very difficult to achieve. Herein, we facilely prepare a unique carbon coating Ge nanospheres with a cubic hollow structure (Ge@C) via a hydrothermal synthesis and subsequent pyrolysis using low-cost GeO 2 as precursors. The hollow Ge@C nanostructure not only provides abundant interior space to alleviate the huge volumetric expansion of Ge upon lithiation, but also facilitates the transmission of lithium ions and electrons. Moreover, experiment analyses and density functional theory (DFT) calculations unveil the excellent lithium adsorption ability, high exchange current density, low activation energy for lithium diffusion of the hollow Ge@C electrode, thus exhibiting significant lithium storage advantages with a large charge capacity (1483 mAh/g under 200 mA g−1), distinguished rate ability (710 mAh/g under 8000 mA g−1) as well as long-term cycling stability (1130 mAh/g after 900 cycles under 1000 mA g−1). Therefore, this work offers new paths for controllable synthesis and fabrication of high-performance Ge based lithium storage nanomaterials. [ABSTRACT FROM AUTHOR]

Constructing a hollow structure inside zeolite is very helpful for improving its performance. Unlike the conventional alkaline etching technique usually operated at high temperature (typically 170 °C) and high pressure (autogenerated in autoclave), here, it is discovered that zeolite MFI nano‐box can be achieved under mild etching conditions of atmospheric pressure and low temperature of 80 °C, making it very attractive for energy conservation and practical applications. A hollow‐structure formation mechanism of protection‐dissolution etching is demonstrated by characterizing MFI crystals obtained under different etching time, temperature, and etchant concentration. The utilization of template agent‐free secondary growth leads to the successful fabrication of a continuous b‐oriented hierarchical MFI zeolite film with desired microstructure of embedded cavities and opened pores. The advantage of the newly constructed film is highlighted by its ultralow k value accompanied with high mechanical strength. [ABSTRACT FROM AUTHOR]

Catalytic 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. [ABSTRACT FROM AUTHOR]

Multiple-component materials with advanced microstructure are increasingly utilized in the development of microwave absorption materials. In this paper, a magnetic hollow sphere composed of Fe 3 O 4 @PS was fabricated by simply depositing Fe 3 O 4 nanoparticles onto the surface-modified PS hollow spheres through electrostatic interactions. The microwave absorption properties of Fe 3 O 4 @PS hollow spheres were studied by varying the loading capacity of Fe 3 O 4. The results show that when the Fe 3 O 4 content is 28.59 wt%, the optimal minimum reflection loss is −26.9 dB with effective absorption bandwidths (RL ≤ −10 dB) exceeding 0.3 GHz. Furthermore, the straightforward combination of the Fe 3 O 4 @PS with MWCNTs enables the enhancement of the microwave absorption up to −41.4 dB at 14.5 GHz, with an effective absorption bandwidth exceeding 5.9 GHz (12.1–18 GHz) at a thickness of 2 mm. This study is expected to provide valuable insights into the design of nanocomposites for microwave absorption applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel and simple scheme for loading aluminum hypophosphite on MOF derivatives. • The dual function of carboxymethyl cellulose: buffer and support layer. • The double-layer hollow nano hybrid is integrated with multiple flame retardant elements. • The flame retardancy of epoxy resin composites is significantly improved after the introduction of AHP/ACP@CMC due to its unique components and nanostructure. Aluminum hypophosphite (AHP) has been used as a flame retardant for a long time. Previous studies about AHP employed in flame retardant materials mostly focus on coating, modification, and complex system. It is valuable to explore simple experimental steps to prepare nano hybrids with AHP and metal–organic frameworks (MOFs). We found acidic substances could etch zeolitic imidazolate framework-67 (ZIF-67) to obtain MOF derivatives. Unfortunately, AHP and ZIF-67 could not directly form a hybrid. Therefore, carboxymethylcellulose (CMC) is introduced as a dual function layer (buffer and support). The CMC resists the complete conversion of ZIF-67 etched by phosphoric acid to amorphous cobalt phosphate hydrate (ACP). Meanwhile, CMC containing hydroxyl groups combines with AHP through electrostatic interaction and coordination bonds. A double-layer hollow MOF derivative is synthesized through this one-stone-two-birds strategy. Due to multiple flame retardant elements and unique nanostructure, this MOF derivative endows epoxy (EP) resin with excellent flame retardancy. With 2.0 wt% addition, the peak heat release rate (pHRR) and total heat release (THR) of EP/AHP/ACP@CMC are decreased by 47.8 and 21.0 %, respectively. This study proposes a novel scheme that converts AHP into MOF derivatives as high-performance FRs. [ABSTRACT FROM AUTHOR]

Two-dimensional transition metal carbides and nitrides (MXenes) have garnered increasing attention in energy storage devices due to their competitive performance. However, the inherent characteristic of two-dimensional materials to restack and aggregate significantly limits the full exploitation of the properties of MXene. In this study, we first explore the etching conditions of V2C MXene via a sealed hydrothermal reaction, and successfully synthesize high-quality accordion-like V2C MXene. Subsequently, two-dimensional V2C MXene nanosheets of small size were attached to the surface of poly-(methyl methacrylate) (PMMA) by self-assembly effect. Three-dimensional self-supporting hollow spherical nanocomposite structures (H–V2C/C) are obtained through a sacrificial template method. Benefiting from the extra reaction space inherent to the hollow structure, along with the stability and conductivity of the carbon material, H–V2C/C can provide abundant active sites, fast ion transport path, and stable physical structure as the cathode, thus significantly improving the electrochemical performance of aqueous zinc-ion batteries (ZIBs). Compared to nanosheet-like V2C MXene, the H–V2C/C cathode material broadens the voltage window of ZIBs from 0.2–1.1 V to 0.2–1.5 V, significantly improving energy density and effective capacity. At a current density of 0.1 A g–1, the H–V2C/C cathode exhibits an initial capacity of 517.3 mAh g–1, which further increases to an ultrahigh capacity of 659.8 mAh g–1 after 89 cycles. Even when the current density is increased to 5 A g–1, the material retains 75.3% of its capacity after 4000 cycles. This study significantly improves the potential of MXene-based material properties in ZIBs through structural design and material modification, providing an idea for the development of the next generation of high-performance energy storage systems. [ABSTRACT FROM AUTHOR]

Transition metal phosphides (TMPs) have emerged as an alternative to precious metals as efficient and low‐cost catalysts for water electrolysis. Elemental doping and morphology control are effective approaches to further improve the performance of TMPs. Herein, Fe‐doped CoP nanoframes (Fe‐CoP NFs) with specific open cage configuration were designed and synthesized. The unique nano‐framework structured Fe‐CoP material shows overpotentials of only 255 and 122 mV at 10 mA cm−2 for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), respectively, overwhelming most transition metal phosphides. For overall water splitting, the cell voltage is 1.65 V for Fe‐CoP NFs at a current density of 10 mA cm−2, much superior to what is observed for the classical nanocubic structures. Fe‐CoP NFs show no activity degradation up to 100 h which contrasts sharply with the rapidly decaying performance of noble metal catalyst reference. The superior electrocatalytic performance of Fe‐CoP NFs due to abundant accessible active sites, reduced kinetic energy barrier, and preferable *O‐containing intermediate adsorption is demonstrated through experimental observations and theoretical calculations. Our findings could provide a potential method for the preparation of multifunctional material with hollow structures and offer more hopeful prospects for obtaining efficient earth‐abundant catalysts for water splitting. [ABSTRACT FROM AUTHOR]

Magnetic/dielectric composite materials with numerous heterointerfaces are highly promising functional materials, which are widely applied in the fields of electromagnetic wave absorption. Constructing heterogeneous structure is beneficial to further enhance the microwave absorption performance of composite materials. However, the process of constructing multi-heterogeneous interfaces is extremely complex. In this work, hollow porous FeCo/Cu/CNTs composite microspheres are prepared by the simple spray drying method and subsequently two-step annealing treatment, which possess abundant heterogeneous interfaces, unique three-dimensional conductive network and magnetic coupling network. This unique structure is beneficial to improving the ability of dielectric loss and magnetic loss, and then achieving an excellent microwave absorption performance. The prepared FeCo/Cu/CNTs-1 composite microspheres maintain a minimum reflection loss (RL) of −48.1 dB and a maximum effective absorption bandwidth of 5.76 GHz at a thickness of 1.8 mm. Generally, this work provides a new idea for designing multi-heterogeneous of microwave absorbing materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • We develop NiCo alloy-decorated nitrogen-doped carbon double-shelled hollow polyhedrons (NC/NiCo DSHPs) as highly efficient catalysts for Li-S batteries. • The distribution of NiCo alloy on both the inner and outer shells ensures sufficient catalytic active sites, which can effective adsorb LiPSs and mitigate the shuttle effect, even at high loadings, and facilitate the conversion between LiPSs and Li 2 S, enabling enhanced redox kinetics of Li-S systems. • Benefiting from the advantages of composition and structure, Li-S batteries, using porous NC/NiCo DSHPs as separator coating material, achieve a high specific capacity of 1310 mAh g-1 at 0.2 C, a superior cycling performance with low capacity fading of 0.045% per cycle at 1 C after 800 cycles. Lithium-sulfur (Li-S) batteries have received significant attention due to their high theoretical energy density. However, the inherent poor conductivity of S and lithium sulfide (Li 2 S), coupled with the detrimental shuttle effect induced by lithium polysulfides (LiPSs), impedes their commercialization. In this study, we develop NiCo alloy-decorated nitrogen-doped carbon double-shelled hollow polyhedrons (NC/NiCo DSHPs) as highly efficient catalysts for Li-S batteries. The distribution of NiCo alloy on both the inner and outer shells provides abundant catalytic active sites, effectively adsorbing LiPSs, mitigating the shuttle effect, and promoting the conversion between LiPSs and Li 2 S, even at high sulfur loadings. This results in enhanced redox kinetics within the Li-S system. Moreover, the highly conductive carbon material framework, enriched with carbon nanotubes and graphitic carbon layers, can greatly promote the efficient electron transportation. Additionally, the improved ion diffusion rates benefiting from the hollow structure can also be realized. By harnessing these synergistic effects, Li-S batteries incorporating the double-shelled NC/NiCo DSHP catalysts achieved a high specific capacity of 1310 mAh/g at 0.2C and a superior rate performance of 621 mAh/g at 4C. Furthermore, excellent cycling performance with ultralow capacity fading rate of only 0.045 % per cycle after 800 cycles at 1C was achieved. When sulfur loading reaches 6 mg cm−2, a high capacity of 4.6 mAh cm−2 at 0.1C after 100 cycles further validates the practical potential of this design. This study presents an innovative approach to alloy catalyst design, offering valuable insights for future research of Li-S batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hollow core–shell structured Co 3 O 4 @CuO-NiO was synthesized through a simple route. • Charge transfer among Co 3 O 4, CuO, and NiO optimizes catalyst's electronic structures. • TOF of the optimal catalyst in NH 3 BH 3 methanolysis is as high as 67.1 min−1. • Possible mechanism for NH 3 BH 3 methanolysis is proposed based on in-situ FTIR results. Catalytic methanolysis of ammonia borane is an integrated hydrogen production/storage technology with bright prospects, while its wide application is impeded by the high-cost of catalysts. In this work, hollow core@shell structured (HCSS) Co 3 O 4 @CuO-NiO with a size of 300–500 nm and a shell thickness of ca. 100 nm has been designed for ammonia borane (NH 3 BH 3) methanolysis for rapid hydrogen release. The possible formation mechanism of HCSS-Co 3 O 4 @CuO-NiO is proposed based on a series of characterization results, which is crucial for the design and preparation of nanocatalysts with similar architectures. Benefiting from the optimized compositions and electronic structures, the best HCSS-Co 3 O 4 @CuO-NiO sample exhibits high catalytic activity in NH 3 BH 3 methanolysis with a turnover frequency of 67.1 min−1, surpassing that of all the noble-metal-free catalysts in previous reports. A possible reaction mechanism of NH 3 BH 3 methanolysis is put forward based on the in-situ Fourier transform infrared spectrometer (FTIR) characterization and kinetic isotope effect (KIE) experimental results. This work supplies a novel avenue for developing cheap and robust catalysts towards NH 3 BH 3 methanolysis by tailoring the catalysts' morphology to hollow core@shell structures. [ABSTRACT FROM AUTHOR]