Three-dimensional Interconnected Pore Research Articles

Engineering Three-Dimensional Interconnected Pores with Plentiful Edge Sites via a Confined Space for Enhanced Oxygen Reduction.

N-Doped carbon sheets based on edge engineering provide more opportunities for improving oxygen reduction reaction (ORR) active sites. However, with regard to the correlation between porous structural configurations and performances, it remains underexplored. Herein, a silica-assisted localized etching method was employed to create two-dimensional mesoporous carbon materials with customizable pore structures, abundant edge sites, and nitrogen functionalities. The mesoporous carbon exhibited superior electrocatalytic performance for the ORR compared to that of a 20 wt % Pt/C catalyst, achieving a half-wave potential of 0.88 V versus RHE, situating them in the leading level of the reported carbon electrocatalysts. Experimental data suggest that the edge graphitic nitrogen sites played a crucial role in the ORR process. The three-dimensional interconnected pores provided a high density of active sites for the ORR and facilitated the efficient transport of electrons. These unique properties make the carbon sheets a promising candidate for highly efficient air cathodes in rechargeable Zn-air batteries.

Agarics-derived porous Fe/C material activated by ZnCl2 and its enhanced microwave absorption performance

Biomass-derived carbon materials retain the unique porous structure of biological raw materials and have environmental advantages, making them a popular choice for electromagnetic microwave absorption research. The microwave absorption performance of biomass-derived carbon materials is largely influenced by their pore structure, which can be controlled by chemical activators. In this study, ZnCl2 was chosen as the activator and de-impregnated agarics with Fe(NO3)3·9 H2O for pretreatment. The Fe(NO3)3·9 H2O can provide magnetic Fe particles for the material to enhance the magnetic loss ability. And the weakly acidic ZnCl2 can avoid the pollution of the environment, and its dehydration and dehydroxylation properties can release the hydrogen and oxygen in the biomass char material in the form of water vapor, and release the hydrogen and oxygen in the biomass carbon material in the form of water vapor, and form a porous structure. porous structure. In addition, ZnCl2 will be converted to ZnO during the activation process, and the removal of ZnO by acid washing will increase the internal pore volume, form a conductive network, and form a rich three-dimensional interconnected pore structure. The pretreated samples were vacuum carbonized at high temperature to obtain agarics-derived porous Fe/C material, which is an excellent lightweight and high-performance microwave absorbing material. The resulting material has a wider absorption bandwidth and improved microwave absorption performance. At a thickness of 2.55 mm and a frequency of 8.31 GHz, the RLmin of Fe/C material is −51.14 dB. Furthermore, at a thickness of 2.13 mm, it has an effective absorption bandwidth of 3.63 GHz, covering most of the X-band.

Advancing carbon dioxide capture: Unravelling structure-property-performance dynamics in graphene related two-dimensional materials

Efficient design of adsorbents for carbon dioxide (CO2) capture is imperative in addressing the challenges caused by climate change. In this study, a comprehensive exploration of solid adsorbents derived from graphene-related two-dimensional materials (GR2Ms) with tunable surface chemistry and structures was undertaken to unravel the intricate structural-property-activity relationships essential for optimizing their CO2 adsorption. Nine key GR2Ms and carbon materials, including two types of (few-layer graphene (FLG), graphene oxide (GO) reduced graphene oxide (rGO) materials), expanded graphite (Exp Gft), rGO-Exp Gft and graphite (Gft), were methodically characterized alongside benchmarked materials such as activated carbon (AC) and molecular sieves (MS). Characterization parameters, i.e. morphology, particle size, interlayer distance, crystallite size, defect density, specific surface area (SSA), total pore volume, micropore volume and pore size, are correlated with CO2 adsorption capacity. Results revealed that the dominant properties influencing CO2 adsorption in GR2Ms are hierarchical porous morphology, defect density (up to 2.38 × 1011 cm−2), SSA (up to ∼271 m2/g), total pore volume (up to 0.86 cm3/g), and micropore volume (up to 0.03 cm3/g), all of which have established positive linear relationships. Conversely, crystallite size (0.38–48 nm) exhibited an inverse (non-linear) relationship with CO2 adsorption capacity under ambient conditions (25 °C and 1 atm). Particle size (8–52 μm), interlayer distance (0.33–0.89 nm) and pore size (4.2–13.3 nm) of GR2Ms showed negligible impact on CO2 adsorption capacity. Remarkably, porous rGO emerged as the top-performing CO2 adsorbent with an enhanced adsorption capacity (5.38 mmol/g) , in comparison with activated carbon (AC, 1.79 mmol/g) and molecular sieve (MS, 1.48 mmol/g). This study establishes a comprehensive structure-property-performance relationship, highlighting the significance of a three-dimensional (3D) hierarchical, open and interconnected pore structure within the graphene network, along with the largest pore volume and minimum crystallite size of rGO. These findings underscore the critical role of structural and porosity attributes of GR2Ms in CO2 adsorption, providing fundamental insights into the interplay between the structure and properties on their CO2 adsorption behavior. This study emphasizes the key pillars for effective adsorbent design and underlines the necessity of optimised control over the structural characteristics and porosity of GR2Ms to enhance their CO2 adsorption capabilities, contributing towards the ambitious net-zero target by 2050.

Ultra-high space utilization of wood/phenolic resin-derived thick carbon electrode for advanced storge devices

The thick electrode design with high packing density of active materials can increase the capacity in a limited space. However, the key challenge is still to develop a system with high space utilization and ensure electron/ion transport in thick electrode. This work proposes an interesting “rebar-concrete” structure, which successfully prepared wood/phenolic resin-derived thick electrode with high space utilization by in-situ polymerization of phenolic resin (concrete) in the wood (rebar) channel. The electrode exhibits an excellent three-dimensional interconnected hierarchical pore structure due to the uniform activation of in-situ anchored KOH particles. The mass loading (35 mg cm−2) and areal capacitance (11F cm−2) of the obtained composite electrode are increased to 446 % and 1257 % of the original balsa wood, respectively. The assembled symmetric supercapacitor (SSC) exhibits a high energy density of 0.63 mWh cm−2 (3.91 mWh cm−3) and an excellent cycle stability (95 % retention after 50 000 cycles), showing good practicability in lighting LEDs or driving a fan. This strategy achieves effective coupling of self-supporting skeleton and powder materials, providing more insights and possibilities for the preparation of high energy density thick electrodes.

High-efficiency and all-weather crude oil spill remediation by an eco-friendly self-heating MXene-coated poly(butylene adipate-co-terephthalate) porous monolith

Frequent oil spill incidents have resulted in serious environmental pollution posing a great threat to human health and ecological system, thus developing new absorbents to efficiently remove and recycle high-viscosity crude oil is attracting more attention. We herein report an eco-friendly flexible poly(butylene adipate-co-terephthalate) (PBAT)-based monolith with MXene (Ti3C2Tx) and polydimethylsiloxane (PDMS) coatings (P-MXene@PBAT monolith) by convenient and economical preparation method for self-heating driven fast crude oil cleanup. Due to unique three-dimensional interconnected pore structure and superior hydrophobicity, the P-MXene@PBAT showed high saturated absorption capacity and cyclic separation efficiency for multifarious low-viscosity oils. The P-MXene@PBAT was endowed with excellent photo/electro-thermal performance via wrapping MXene layer. The maximum surface temperature of monolith quickly reached up to 81 °C under 1.0 kW m−2 (1.0 sun) irradiation and 91 °C under 8 V voltage, respectively. Furthermore, the P-MXene@PBAT could self-heat crude oil to dramatically decrease oil viscosity and accelerate separation process. Specially, the P-MXene@PBAT was able to continuously separate crude oil from water with a simple pump-assisted absorption device (crude oil flux of 204 kg m−2 h−1), which adapted to varied working conditions by coupling solar heating and Joule heating. Such environmental-friendly all-weather absorbent design provides a sustainable strategy for efficient remediation of crude oil spill.

Tuning Mass Transport in Electrocatalysis Down to Sub-5 nm through Nanoscale Grade Separation.

Nano and single-atom catalysis open new possibilities of producing green hydrogen (H2 ) by water electrolysis. However, for the hydrogen evolution reaction (HER) which occurs at a characteristic reaction rate proportional to the potential, the fast generation of H2 nanobubbles at atomic-scale interfaces often leads to the blockage of active sites. Herein, a nanoscale grade-separation strategy is proposed to tackle mass-transport problem by utilizing ordered three-dimensional (3d) interconnected sub-5 nm pores. The results reveal that 3d criss-crossing mesopores with grade separation allow efficient diffusion of H2 bubbles along the interconnected channels. After the support of ultrafine ruthenium (Ru), the 3d mesopores are on a superior level to two-dimensional system at maximizing the catalyst performance and the obtained Ru catalyst outperforms most of the other HER catalysts. This work provides a potential route to fine-tuning few-nanometer mass transport during water electrolysis.

Performance of polymer electrolyte fuel cell under wet/dry conditions with hydrophilic and hydrophobic electrospun microporous layers

The electrospinning method is used to fabricate the microporous layers (MPL). The hydrophobic and hydrophilic electrospun MPLs (E-MPLs) are realized by using acetylene black and pigmented carbon black in the electrospinning ink, respectively. Scanning electron microscope shows that the E-MPLs have three-dimensional inter-connected pore structure formed by disordered nanofibers. Mercury intrusion porosimetry results indicate that the E-MPLs have larger porosity (more than 85%) and wider pore size distribution (0.8–4 μm) compared with the commercial MPL (from SGL 29BC). Hydrophobic E-MPL exhibits lower mass transport resistance at 100% relative humidity (RH) due to its larger pore size and better water drainage capability, while the hydrophilic E-MPL shows lower ohmic resistance at 40% RH due to its higher water retention capability. Fuel cell with a double-layer E-MPL, an integrated MPL containing a hydrophilic layer and a hydrophobic layer, is found to perform well under wider RH range. The fuel cell with double-layer E-MPL is found to have a better dynamic response to a current step, in that it has lower amplitude of voltage undershoot and overshoot, and reaches a steady state more quickly.

Natural bamboo-derived O-doped rocky electrocatalyst for high-efficiency electrochemical reduction of O2 to H2O2

The in-situ H2O2 electrosynthesis by two-electron oxygen reduction reaction employing renewable electricity is a promising alternative to traditional anthraquinone process due to its security, environmental friendliness and excellent cost effectiveness, which requires high-performance, cost-effective and environmental-friendly electrocatalysts. A bamboo-derived O-doped rocky electrocatalyst is developed by facile pyrolysis and acid treatment for high-efficiency electroreduction of O2 to H2O2. Three-dimensional interconnected hierarchical pores in rocky electrocatalysts expose abundant electroactive sites and facilitate mass transfer of reaction species. From the results of rotating ring-disk electrode test, a H2O2 selectivity up to 80% and superior electrocatalytic activity of the prepared electrocatalyst are achieved by surface oxygen functionalization induced by acid treatment. At the optimal catalyst loading of 2 mg cm−2, prominent H2O2 productivity of 1037 mmol gcatalyst−1h−1 with high current efficiency up to 74.1% is achieved at 30 mA cm−2 by air-breathing cathode. Higher H2O2 productivity (1525 mmol gcatalyst−1h−1) is yielded by further raising the current density to 50 mA cm−2. Moreover, the durability test of the cathode through ten consecutive runs demonstrates its great stability for electrocatalytic generation of H2O2. This work inspires the development of promising biomass-derived electrocatalysts for green and sustainable on-site H2O2 electrosynthesis.

Effects of dynamic flow rates on degradation deposition behavior of Mg scaffold

Degradability of bone tissue engineering scaffold that matching the regeneration rate could allow a complete replacement of host tissue. However, the porous structure of biodegradable Mg scaffolds certainly generated high specific surface area, and the three-dimensional interconnected pores provided fast pervasive invasion entrance for the corrosive medium, rising concern of the structural integrity during the degradation. To clarify the structural evolution of the three-dimensional (3D) porous structure, semi-static immersion tests were carried out to evaluate the degradation performance in our previous study. Nevertheless, dynamic immersion tests mimicking the in vivo circulatory fluid through the interconnected porous structure have yet been investigated. Moreover, the effects of dynamic flow rates on the degradation deposition behavior of 3D porous Mg scaffolds were rarely reported. In this study, Mg scaffolds degraded at three flow rates exhibited different degradation rates and deposition process. A flow rate of 0.5 mL/min introduced maximum drop of porosity by accumulated deposition products. The deposition products provided limited protection against the degradation process at a flow rate of 1.0 mL/min. The three-dimensional interconnected porous structure of Mg scaffold degraded at 2.0 mL/min well retained after 14 days showing the best interconnectivity resistance to the degradation deposition process. The dynamic immersion tests disclosed the reason for the different degradation rates on account of flow rates, which may bring insight into understanding of varied in vivo degradation rates related to implantation sites.

Influence of Culture Period on Osteoblast Differentiation of Tissue-Engineered Bone Constructed by Apatite-Fiber Scaffolds Using Radial-Flow Bioreactor.

With the limitation of autografts, the development of alternative treatments for bone diseases to alleviate autograft-related complications is highly demanded. In this study, a tissue-engineered bone was formed by culturing rat bone marrow cells (RBMCs) onto porous apatite-fiber scaffolds (AFSs) with three-dimensional (3D) interconnected pores using a radial-flow bioreactor (RFB). Using the optimized flow rate, the effect of different culturing periods on the development of tissue-engineered bone was investigated. The 3D cell culture using RFB was performed for 0, 1 or 2 weeks in a standard medium followed by 0, 1 or 2 weeks in a differentiation medium. Osteoblast differentiation in the tissue-engineered bone was examined by alkaline phosphatase (ALP) and osteocalcin (OC) assays. Furthermore, the tissue-engineered bone was histologically examined by hematoxylin and eosin and alizarin red S stains. We found that the ALP activity and OC content of calcified cells tended to increase with the culture period, and the differentiation of tissue-engineered bone could be controlled by varying the culture period. In addition, the employment of RFB and AFSs provided a favorable 3D environment for cell growth and differentiation. Overall, these results provide valuable insights into the design of tissue-engineered bone for clinical applications.

Three-dimensional hierarchical porous carbon derived from resorcinol formaldehyde-zinc tatrate/poly(styrene-maleic anhydride) for high performance supercapacitor electrode

Herein, we propose a three-dimensional hierarchical porous carbon (THPC) derived from interpenetrating polymer networks (IPNs) of resorcinol formaldehyde-zinc tartrate and poly(styrene-maleic anhydride) (RF-Zn/PSMA), which was prepared via a gel swelling method. The three-dimensional hierarchical and interconnected pore structure involving micro-, meso- and macropores benefits from the synergistic pore-forming effect of PSMA pyrolysis and zinc tartrate decomposition during carbonization process. A high specific surface area of 742 m2 g−1 together with a cheese-like morphology was found for obtained THPC, exhibiting a high specific capacitance of 235 F g−1 at 1 A g−1 in 6 M KOH. THPC assembled symmetrical supercapacitor using 6 M KOH and 1 M Na2SO4 as electrolytes deliver energy outputs of 6.47 and 15.3 Wh kg−1 at 100 and 180 W kg−1, respectively. More attractively, the assembled supercapacitor based on the THPC achieves a high energy outputs of 50.45 Wh kg−1 at 350 W kg−1 in EMIMBF4 under wide potential window of 3.5 V, indicating its practical application prospect. Our findings open up new playgrounds for the design and electrochemical application of hierarchical porous carbon using IPNs as precursor.

Evaluating the morphology of the degradation layer of pure magnesium via 3D imaging at resolutions below 40 nm

Magnesium is attractive for the application as a temporary bone implant due to its inherent biodegradability, non-toxicity and suitable mechanical properties. The degradation process of magnesium in physiological environments is complex and is thought to be a diffusion-limited transport problem. We use a multi-scale imaging approach using micro computed tomography and transmission X-ray microscopy (TXM) at resolutions below 40 nm. Thus, we are able to evaluate the nanoporosity of the degradation layer and infer its impact on the degradation process of pure magnesium in two physiological solutions. Magnesium samples were degraded in simulated body fluid (SBF) or Dulbecco's modified Eagle's medium (DMEM) with 10% fetal bovine serum (FBS) for one to four weeks. TXM reveals the three-dimensional interconnected pore network within the degradation layer for both solutions. The pore network morphology and degradation layer composition are similar for all samples. By contrast, the degradation layer thickness in samples degraded in SBF was significantly higher and more inhomogeneous than in DMEM+10%FBS. Distinct features could be observed within the degradation layer of samples degraded in SBF, suggesting the formation of microgalvanic cells, which are not present in samples degraded in DMEM+10%FBS. The results suggest that the nanoporosity of the degradation layer and the resulting ion diffusion processes therein have a limited influence on the overall degradation process. This indicates that the influence of organic components on the dampening of the degradation rate by the suppression of microgalvanic degradation is much greater in the present study.

An acid induction strategy to construct an ultralight and durable amino-functionalized graphene oxide aerogel for enhanced quinoline pollutants extraction from coking wastewater

The direct emission of quinoline in coking wastewater has great harm to human health and environmental quality. Therefore, it is urgent to develop advanced materials for efficient adsorption of quinoline in wastewater. In this study, a novel three-dimensional amino-functionalized graphene oxide aerogel (MGOA) was prepared by an acid induction strategy, which triggers the esterification and amidation of graphene oxide (GO) nanosheets and ammonium citrate. This strategy not only improves the chemical stability and mechanical strength of as-prepared MGOA, but also provides a large number of effective adsorption sites to achieve the efficient adsorption towards quinoline. MGOA has the advantages of three-dimensional interconnected hierarchical pore structure, large specific surface area, and low density. When the initial quinoline concentration is 50 mg L−1, the adsorption capacity (qe) of MGOA towards quinoline is as high as 103 mg g−1 at 298 K. More importantly, in the column adsorption system, the distribution coefficient (PC) at 10% breakthrough is 14.16 mg g−1 μM−1, which is the highest level yet reported. MGOA exhibits good reusability and outstanding solid-liquid separation advantage during eight adsorption-desorption cycles. Density functional theory and van der Waals surface electrostatic potential were used to investigated the adsorption behavior of quinoline on aerogel. The binding force between MGOA and quinoline molecule is strong, with an adsorption energy up to −78.68 kJ mol−1. Thus, MGOA is considered as a promising candidate for removing quinoline contaminants from aqueous solutions.

Porous Co2P film coated on carbon fiber as highly performance electrocatalyst toward overall water splitting

Designing porous active materials and enhancing their contact with conductive substrates is an effective strategy to improve electrolytic water splitting performance of noble metal-free catalysts. Herein, a facile nanostructured electrode, composed of porous Co2P films coated on carbon fiber (CF@P–Co2P), is designed and prepared. The unique three-dimensional interconnected pore structure of Co2P and the close contact between porous Co2P and CF not only increase specific surface areas to expose abundant catalytic sites but also stimulate the transport of electron, mass and gaseous products in catalytic process. Benefit from the reasonable electrode structure, the self-supported CF@P–Co2P electrodes present perfect performance with only needing overpotentials of 107.7/175.5/141.8 mV for hydrogen evolution reaction (HER) in acidic/neutral/alkaline solution and 269.4 mV for oxygen evolution reaction (OER) in alkaline solution to get current density of 20 mA cm−2. In addition, alkaline electrolyzer equipped with CF@P–Co2P bifunctional electrodes only needs a cell voltage of 1.657 V to get water-splitting current density of 20 mA cm−2. Even better, the electrolyzer can continuously electrolyze over 50 h with negligibly decreasing current density and the Faraday efficiency is close to 100% toward both HER and OER.

Ordered Bicontinuous Mesoporous Polymeric Semiconductor Photocatalyst.

Owning triply periodic minimal surfaces and three-dimensional (3D) interconnected pores, bicontinuous porous materials have drawn enormous attention due to their great academic interest and potential applications in many fields including energy and catalysis. However, their synthesis has remained a great challenge. Here, we demonstrate the synthesis of a bicontinuous porous organic semiconductor photocatalyst, which involves the preparation of SiO2 with a shifted double diamond (DD) structure through solvent evaporation-induced self-assembly of a polystyrene-block-poly(ethylene oxide) diblock copolymer and tetraethyl orthosilicate, followed by SiO2-templated self-condensation of melamine monomers in a vacuum. Strikingly, the resultant DD-structured graphitic carbon nitride (g-CN) possesses two sets of 3D continuous mesopores with a mean diameter of 14 nm, which afford a high specific surface area of 131 m2 g-1 and an optical band gap of 2.8 eV. Being a visible-light-driven photocatalyst, the bicontinuous mesoporous g-CN exhibits high catalytic activity for water splitting to generate H2 (6831 μmol g-1 h-1) with excellent cycling stability. This study provides a protocol for the construction of ordered mesoporous materials containing 3D continuous channels, which holds promise for catalysis applications.

Synthesis of micro-sized porous antimony via vapor dealloying for high-performance Na-ion battery anode

Antimony (Sb) is a promising sodium-ion anode material due to sustaining a high theoretical capacity of 660 mAh g−1. However, the huge volumetric change of 293% leads to serious pulverization and poor cycling stability. Herein, we design micro-sized porous Sb (PSb) via one-step chemical vapor dealloying. The as-prepared PSb owns three-dimensional nano-skeleton and interconnected pores, which enables PSb a high tap density (2.33 g cm−3), high electrochemical properties and robust ability to alleviate the volumetric expansion of sodiation. The PSb anode exhibits initial charge and discharge capacities of 834 and 517 mAh g−1 at a current density of 50 mA g−1, corresponding to an initial Coulombic efficiency (ICE) of 61.8%. And a high capacity retention of 80% is obtained after 120 cycles at a current density of 50 mA g−1. Moreover, the PSb sustains an outstanding rate performance with a capacity of 300 mAh g−1 even at a large current density of 3000 mA g−1. Compared with micro-Sb, the PSb exhibits a lower electrode swelling of 63.96% because the unique porous structure can effectively alleviate the volume variation and pulverization of Sb during cycling. The enhanced performance of PSb enables it as a promising anode material for advanced Sodium-Ion Batteries.

Antibacterial silver-diatomite nanocomposite ceramic with low silver release

Abstract There is an urgent need for an effective and long-lasting ceramic filter for point-of-use water treatment. In this study, silver-diatomite nanocomposite ceramic filters were developed by an easy and effective method. The ceramic filters have a three-dimensional interconnected pore structure and porosity of 50.85%. Characterizations of the silver-diatomite nanocomposite ceramic filters were performed using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. Silver nanoparticles were confirmed to be formed in situ in the ceramic filter. The highest silver concentration in water was 0.24 μg/L and 2.1 μg/L in short- and long-term experiments, indicating very low silver-release properties of silver-diatomite nanocomposite ceramic filter. The nanocomposite ceramics show strong bactericidal activity. When contact time with Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) of 105 colony forming units (CFU)/mL exceeded 3 h, the bactericidal rates of the four different silver content ceramics against E. coli and S. aureus were all 100%. Strong bactericidal effect against E. coli with initial concentration of 109 CFU/mL were also observed in ceramic newly obtained and ceramic immersed in water for 270 days, demonstrating its high stability. The silver-diatomite nanocomposite ceramic filters could be a promising candidate for point-of-use water treatment.

Functionalized Biomimetic Composite Nanfibrous Scaffolds with Antibacterial and Hemostatic Efficacy for Facilitating Wound Healing.

An ideal wound dressing should not only promote rapid hemostasis and wound healing but also have good biocompatibility, antimicrobial activities, and should mimic the skin's physiological function. In the present study, five O-quaternized chitosan (QAS-CS) materials with satisfactory antibacterial activity and no cytotoxicity were successfully synthesized. Furthermore, we reported the synthesis and characterization of the two novel composite nanofibrous scaffolds consisting of selfdeveloped collagen (COL), quaternary ammonium salt (QAS) or QAS-CS and polycaprolactone (PCL) or polyvinyl alcohol (PVA) with an electrospinning approach. The PCL/COL/QAS (PCQ3) and PVA/COL/QAS-CS (PCQC5) materials exhibited uniform, three-dimensional interconnected pore structure, high porosity, and large specific surface area, which can mimic the architecture and biological functions of the native extracellular matrix microenvironment and provide suitable conditions for cell adhesion, proliferation, and differentiation. The growth and proliferation of human immortalized epidermal (HaCaT) cells on PCQ3 and PCQC5 materials was good, and the result of blood compatibility and the skin irritant test indicated that the scaffolds had good blood compatibility and did not exhibit significant irritability. Importantly, PCQ3 and PCQC5 have notable effects on rapid hemostasis, antibacterial activity, and anti-inflammation, promote wound healing, and display other superior benefits in comparison to available products. Overall, PCQ3 and PCQC5 are proposed to be good candidates for skin tissue engineering applications and can be used on different types of wounds.

Novel method of fabricating ultra-light aluminum borate foams with hierarchical pore structure

Ultra-light aluminum borate foams (ABFs) with porosity ranging from 92.18 to 86.82 vol% were fabricated by combining foam-casting and freeze-drying using alumina and boron carbide as raw materials. The effects of heating temperature on phase evaluation and the influence of solid content of slurries on the physical properties and formation mechanism of the three-dimensional interconnected hierarchical pore structure in ABFs were investigated. The contacting of bubbles, burning loss of organics, replacement of ice crystals by alcohol, and interlocking of rod-like aluminum borate crystal together created a hierarchical pore structure in foams. The results revealed that the performance and microstructure of ABFs could be controlled by adjusting the solid content of slurries.

Nanoporous gold–Nitrogen–doped carbon nano-onions all-solid-state micro-supercapacitor

The faster growth of the microelectronics industry and consumer’s demand for tiny, portable electronic devices increases the necessity of micro-scale energy storage units. Micro-supercapacitors have potential to support tiny micro-electronic devices by replacing or complimenting batteries and electrolytic capacitors. Nanoporous gold (NPG)–Nitrogen doped carbon nano-onions (NCNO) based micro-supercapacitor is an attempt to develop an energy storage unit that is compatible with microelectronic devices. A simple two-step process of thermal evaporation followed by dealloying and electrophoretic deposition were used for NPG growth and NPG–NCNO electrode preparation. The process is economical and easily scalable Nanoporous gold (NPG) is an attractive material for current collector due to its three-dimensional interconnected pores with high electrical conductivity and high surface area for NCNO loading. NPG–NCNO micro-supercapacitor device shows an areal capacitance 1.16 mF cm−2. The maximum energy density and power density obtained from NPG–NCNO micro-supercapacitor were 0.16 μWh cm−2 and 24.87 μW cm−2 at the scan rate of 10 mVs−1 and 200 mVs−1 respectively.