Hierarchical Nanoboxes Research Articles

Reinforcement of Electrocatalytic Oxygen Evolution Activity Enabled by Constructing Silver-Incorporated NiCo-PBA@NiFe-LDH Hierarchical Nanoboxes.

Complicated oxygen evolution reaction (OER) poses the bottleneck in improving the efficiency of hydrogen production through water electrolysis. Herein, an integrated strategy to modulate the electronic structure of NiFe layered double hydroxide (NiFe-LDH) is reported by constructing Ag-incorporated NiCo-PBA@NiFe-LDH heterojunction with a hierarchical hollow structure. This "double heterojunction" facilitates local charge polarization at the interface, thereby promoting electron transfer and reducing the adsorption energy of intermediates, ultimately enhancing the intrinsic activity of the catalyst. It is noteworthy that an exchange bias field is observed between NiCo-PBA and NiFe-LDH, which will be conducive to regulating the electron spin states of metals and facilitating the production of triplet oxygen. Additionally, the unique hierarchical nanoboxes provide a large specific surface area that ensures adequate exposure to adsorption sites and active sites. Profiting from the synergistic advantages, the overpotential is as low as 190mV at a current density of 10mAcm-2, with a low Tafel slope of 21mVdec-1. Moreover, density functional theory (DFT) calculation further substantiated that the incorporation of Ag in the heterojunction can effectively reduce the adsorption energy of reactant intermediates and enhance the conductivity.

Hierarchical Hollow CoWO4-Co(OH)2 Heterostructured Nanoboxes Enabling Efficient Water Oxidation Electrocatalysis.

Rational design and construction of well-defined hollow heterostructured nanomaterials assembled by ultrathin nanosheets overtakes crucial role in developing high-efficiency oxygen evolution reaction (OER) electrocatalysts. Herein, a reliable metal-organic framework-mediated and cation-exchange strategy to tune the geometric structure and multicomponent heterostructures has been proposed for the fabrication of hollow CoWO4-Co(OH)2 hierarchical nanoboxes assembled by rich ultrathin nanosheets. Benefiting from the hierarchical hollow nanostructure, the CoWO4-Co(OH)2 nanoboxes offer plenty of metal active centers available for reaction intermediates. Moreover, the well-defined nanointerfaces between CoWO4 and Co(OH)2 can function as the bridge for boosting the efficient electron transfer from CoWO4 to Co(OH)2. As a consequence, the optimized CoWO4-Co(OH)2 nanoboxes can exhibit outstanding electrocatalytic performance toward OER by delivering 10 mA cm-2 with a low overpotential of 280 mV and a small Tafel slope of 70.6 mV dec-1 as well as outstanding electrochemical stability. More importantly, this CoWO4-Co(OH)2 heterostructured nanocatalyst can couple with Pt/C to drive overall water splitting to achieve 10 mA cm-2 with a voltage of 1.57 V.

Shape-controlled hollow Cu2O@CuS nanocubes with enhanced photocatalytic activities towards degradation of tetracycline

ABSTRACT In view of recent advances in photodegradation of antibiotics, low cost and stable photocatalyst remain rare. In this article, shape-controlled Cu2O@CuS nanocubes with the larger specific surface area were successfully prepared via a simple template-engaged strategy. Cu2O nanocubes were synthesized through a reduction method as original templates, the core-shelled Cu2O@CuS nanocubes were formed by sulphuration with Na2S as sulphur source, and the Cu2O core can be incompletely removed by Na2S2O3 to generate the Cu2O@CuS nanoboxes. Herein, hierarchical nanoboxes with two-layered Cu2O@CuS were used as photocatalyst materials for photocatalytic degradation of tetracycline (TC). The obtained nanocubes manifested high specific surface area (39.65 m2 g−1) and large pore volume (12.3 cm3 g−1). The degradation performance for TC was investigated in detail, including the effect of parameters such as photocatalyst, pH and catalyst dosage. The results indicated that degradation efficiencies were higher than 90% under visible light. Moreover, the degradation efficiency was 71% after six times.

Rational design of double-shelled Cu2MoS4@N-doped carbon hierarchical nanoboxes toward fast and stable sodium-ion batteries

Double-shelled Cu2MoS4@NC nanoboxes, composed of an outer shell of N-doped carbon supported on the inner shell of hierarchical Cu2MoS4 nanosheets, are synthesized by a delicate template-based strategy and exhibit enhanced sodium storage performance.

Rationally Designed Three-Layered Cu2 S@Carbon@MoS2 Hierarchical Nanoboxes for Efficient Sodium Storage.

Hybrid materials, integrating the merits of individual components, are ideal structures for efficient sodium storage. However, the construction of hybrid structures with decent physical/electrochemical properties is still challenging. Now, the elaborate design and synthesis of hierarchical nanoboxes composed of three-layered Cu2 S@carbon@MoS2 as anode materials for sodium-ion batteries is reported. Through a facile multistep template-engaged strategy, ultrathin MoS2 nanosheets are grown on nitrogen-doped carbon-coated Cu2 S nanoboxes to realize the Cu2 S@carbon@MoS2 configuration. The design shortens the diffusion path of electrons/Na+ ions, accommodates the volume change of electrodes during cycling, enhances the electric conductivity of the hybrids, and offers abundant active sites for sodium uptake. By virtue of these advantages, these three-layered Cu2 S@carbon@MoS2 hierarchical nanoboxes show excellent electrochemical properties in terms of decent rate capability and stable cycle life.

Rationally Designed Three‐Layered Cu2S@Carbon@MoS2 Hierarchical Nanoboxes for Efficient Sodium Storage

AbstractHybrid materials, integrating the merits of individual components, are ideal structures for efficient sodium storage. However, the construction of hybrid structures with decent physical/electrochemical properties is still challenging. Now, the elaborate design and synthesis of hierarchical nanoboxes composed of three‐layered Cu2S@carbon@MoS2 as anode materials for sodium‐ion batteries is reported. Through a facile multistep template‐engaged strategy, ultrathin MoS2 nanosheets are grown on nitrogen‐doped carbon‐coated Cu2S nanoboxes to realize the Cu2S@carbon@MoS2 configuration. The design shortens the diffusion path of electrons/Na+ ions, accommodates the volume change of electrodes during cycling, enhances the electric conductivity of the hybrids, and offers abundant active sites for sodium uptake. By virtue of these advantages, these three‐layered Cu2S@carbon@MoS2 hierarchical nanoboxes show excellent electrochemical properties in terms of decent rate capability and stable cycle life.

The effect of nanostructures on high pressure intrusion–extrusion of water and electrolyte solutions in hierarchical nanoboxes of silicalite-1

A drastic effect of the presence of cavities on high pressure intrusion–extrusion of LiCl aqueous solution in silicalite-1 nanoboxes is observed.

Multidimensional Integrated Chalcogenides Nanoarchitecture Achieves Highly Stable and Ultrafast Potassium-Ion Storage.

Potassium-ion batteries (KIBs) have come into the spotlight in large-scale energy storage systems because of cost-effective and abundant potassium resources. However, the poor rate performance and problematic cycle life of existing electrode materials are the main bottlenecks to future potential applications. Here, the first example of preparing 3D hierarchical nanoboxes multidimensionally assembled from interlayer-expanded nano-2D MoS2 @dot-like Co9 S8 embedded into a nitrogen and sulfur codoped porous carbon matrix (Co9 S8 /NSC@MoS2 @NSC) for greatly boosting the electrochemical properties of KIBs in terms of reversible capacity, rate capability, and cycling lifespan, is reported. Benefiting from the synergistic effects, Co9 S8 /NSC@MoS2 @NSC manifest a very high reversible capacity of 403 mAh g-1 at 100 mA g-1 after 100 cycles, an unprecedented rate capability of 141 mAh g-1 at 3000 mA g-1 over 800 cycles, and a negligible capacity decay of 0.02% cycle-1 , boosting promising applications in high-performance KIBs. Density functional theory calculations demonstrate that Co9 S8 /NSC@MoS2 @NSC nanoboxes have large adsorption energy and low diffusion barriers during K-ion storage reactions, implying fast K-ion diffusion capability. This work may enlighten the design and construction of advanced electrode materials combined with strong chemical bonding and integrated functional advantages for future large-scale stationary energy storage.

Hierarchical Nanoboxes Composed of Co9 S8 -MoS2 Nanosheets as Efficient Electrocatalysts for the Hydrogen Evolution Reaction.

The development of hydrogen evolution catalysts based on nonprecious metals is essential for the practical application of water-splitting devices. Herein, the synthesis of Co9 S8 -MoS2 hierarchical nanoboxes (HNBs) as efficient catalysts for the hydrogen evolution reaction (HER) is reported. The surface of the hollow cubic structure was organized by CoMoS4 nanosheets formed through the reaction of MoS42- and Co2+ released from the cobalt zeolite imidazole framework (ZIF-67) templates under reflux in a mixture of water/ethanol. The formation process for the CoMoS4 HNB structures was characterized by TEM images recorded at various reaction temperatures. The amorphous CoMoS4 HNBs were converted through sequential heat treatments into CoSx -MoS2 and Co9 S8 -MoS2 HNBs. Owing to their unique chemical compositions and structural features, Co9 S8 -MoS2 HNBs have a high specific surface area (124.6 m2 g-1 ) and superior electrocatalytic performances for the HER. The Co9 S8 -MoS2 HNBs exhibit a low overpotential (η10 ) of 106 mV, a low Tafel slope of 51.8 mV dec-1 , and long-term stability in an acidic medium. The electrocatalytic activity of Co9 S8 -MoS2 HNBs is superior to that of recently reported values, and these HNBs prove to be promising candidates for the HER.