scholarly journals Bioinspired synthesis of SnO crosses as backbone in artificial sponges

2019 ◽  
Vol 377 (2150) ◽  
pp. 20190130
Author(s):  
Timotheus Jahnke ◽  
Stefan Kilper ◽  
Andrea Knöller ◽  
Franz Brümmer ◽  
Marc Widenmeyer ◽  
...  
Keyword(s):  
High Surface ◽  
Active Material ◽  
High Surface Area ◽  
Three Dimensional ◽  
Direct Production ◽  
Calcareous Sponges ◽  
Bioinspired Synthesis ◽  
Hydrothermal Approach ◽  
Chemical Conditions ◽  
P Type

The distinct electronic properties, including p-type semiconducting and a wide optical band gap, renders SnO suitable for applications such as microelectronic devices, gas sensors and electrodes. However, the synthesis of SnO is rather challenging due to the instability of the oxide, which is usually obtained as a by-product of SnO 2 fabrication. In this work, we developed a bioinspired synthesis, based on a hydrothermal approach, for the direct production of SnO nanoparticles. The amount of mineralizer, inducing the precipitation, was identified, which supports a template-free formation of the nanosized SnO particles at low temperature and mild chemical conditions. Moreover, the SnO nanoparticles exhibit a shape of unique three-dimensional crosses similar to the calcite crosses present in the calcareous sponges. We demonstrated that SnO crosses are evenly distributed and embedded in an organic scaffold by an ice-templating approach, in this way closely mimicking the structure of calcareous sponges. Such scaffolds, reinforced by an active material, here SnO, could be used as filters, sensors or electrodes, where a high surface area and good accessibility are essential. This article is part of the theme issue ‘Bioinspired materials and surfaces for green science and technology (part 2)’.

scholarly journals Glucose/Graphene-Based Aerogels for Gas Adsorption and Electric Double Layer Capacitors

Polymers ◽  
2018 ◽  
Vol 11 (1) ◽  
pp. 40 ◽  
Author(s):  
Kang-Kai Liu ◽  
Biao Jin ◽  
Long-Yue Meng
Keyword(s):  
Gas Adsorption ◽  
High Surface ◽  
Aqueous Media ◽  
High Surface Area ◽  
Three Dimensional ◽  
High Specific Capacitance ◽  
Mesopore Size Distribution ◽  
Excellent Electrochemical Performance ◽  
Double Layer Capacitors ◽  
Hydrothermal Reduction

In this study, three-dimensional glucose/graphene-based aerogels (G/GAs) were synthesized using the hydrothermal reduction and CO2 activation method. Graphene oxide (GO) was used as a matrix, and glucose was used as a binder for the orientation of the GO morphology in an aqueous media. We determined that G/GAs exhibited narrow mesopore size distribution, a high surface area (763 m2 g−1), and hierarchical macroporous and mesoporous structures. These features contributed to G/GAs being promising adsorbents for the removal of CO2 (76.5 mg g−1 at 298 K), CH4 (16.8 mg g−1 at 298 K), and H2 (12.1 mg g−1 at 77 K). G/GAs presented excellent electrochemical performance, featuring a high specific capacitance of 305.5 F g−1 at 1 A g−1, and good cyclic stability of 98.5% retention after 10,000 consecutive charge-discharge cycles at 10 A g−1. This study provided an efficient approach for preparing graphene aerogels exhibiting hierarchical porosity for gas adsorption and supercapacitors.

Hierarchical Nano/Micro-structured Surfaces with High Surface Area/Volume Ratios

2021 ◽  
pp. 1-36
Author(s):  
Ketki Lichade ◽  
Yizhou Jiang ◽  
Yayue Pan
Keyword(s):  
Surface Structure ◽  
Surface Area ◽  
Light Trapping ◽  
High Surface ◽  
High Surface Area ◽  
Three Dimensional ◽  
Structure Design ◽  
Surface Structures ◽  
Structured Surfaces ◽  
Design And Manufacture

Abstract Recently, many studies have investigated additive manufacturing of hierarchical surfaces with high surface area/volume (SA/V) ratios, and their performance has been characterized for applications in next-generation functional devices. Despite recent advances, it remains challenging to design and manufacture high SA/V ratio structures with desired functionalities. In this study, we established the complex correlations among the SA/V ratio, surface structure geometry, functionality, and manufacturability in the Two-Photon Polymerization (TPP) process. Inspired by numerous natural structures, we proposed a 3-level hierarchical structure design along with the mathematical modeling of the SA/V ratio. Geometric and manufacturing constraints were modeled to create well-defined three-dimensional hierarchically structured surfaces with a high accuracy. A process flowchart was developed to design the proposed surface structures to achieve the target functionality, SA/V ratio, and geometric accuracy. Surfaces with varied SA/V ratios and hierarchy levels were designed and printed. The wettability and antireflection properties of the fabricated surfaces were characterized. It was observed that the wetting and antireflection properties of the 3-level design could be easily tailored by adjusting the design parameter settings and hierarchy levels. Furthermore, the proposed surface structure could change a naturally-hydrophilic surface to near-superhydrophobic. Geometrical light trapping effects were enabled and the antireflection property could be significantly enhanced (>80% less reflection) by the proposed hierarchical surface structures. Experimental results implied the great potential of the proposed surface structures for various applications such as microfluidics, optics, energy, and interfaces.

scholarly journals Green and facile synthesis of cerium doped Ni3Fe electrocatalyst for efficient oxygen evolution reaction

2020 ◽  
Vol 34 (2) ◽  
pp. 353-363
Author(s):  
F. Kanwal ◽  
A. Batool ◽  
R. Akbar ◽  
S. Asim ◽  
M. Saleem
Keyword(s):  
Oxygen Evolution ◽  
Oxygen Evolution Reaction ◽  
Large Scale ◽  
Low Cost ◽  
High Surface ◽  
High Surface Area ◽  
Three Dimensional ◽  
Alkaline Electrolyte ◽  
Hydrogen Electrode ◽  
Molar Ratios

Electrochemical water splitting is the most promising pathway to produce high-purity hydrogen to alleviate global energy crisis. This reaction demands inexpensive, efficient and robust electrocatalyst for its commercial use. Herein, we demonstrate an effective, facile and scalable method for the synthesis of cerium doped Ni3Fe nanostructures as an electrocatalyst for oxygen evolution reaction (OER) by following simple chemical bath deposition route. The different molar ratios (3, 6 and 12 mM) of cerium in the chemical bath were used to study its effect on the structural and the electrochemical properties of the Ni3Fe nanostructured films. Doping of cerium contents induced variations in the morphology of deposited Ni3Fe nanostructures. The optimized electrocatalyst Ni3Fe/Ce-6 yielded high surface area catalyst nanosheets uniformly deposited on three-dimensional conductive scaffold to ensure increase in the exposure of doped Ni3Fe catalytic sites with high electrical conductivity. As a result, this earth-abundant electrocatalyst affords high OER performance with a small overpotential of 310 mV versus reversible hydrogen electrode (RHE) at 10 mA cm-2 and retains good stability up to ~ 10 h in alkaline electrolyte. This scalable strategy has great potential in future advancement of efficient and low-cost electrocatalysts for their large-scale application in energy conversion systems.                     KEY WORDS: Oxygen evolution, Electrocatalyst, Ni3Fe nanostructures, Cerium, Alkaline electrolyte   Bull. Chem. Soc. Ethiop. 2020, 34(2), 353-363 DOI: https://dx.doi.org/10.4314/bcse.v34i2.12

scholarly journals Linear-Polyethyleneimine-Templated Synthesis of N-Doped Carbon Nanonet Flakes for High-performance Supercapacitor Electrodes

Nanomaterials ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 1225 ◽  
Author(s):  
Dengchao Xia ◽  
Junpeng Quan ◽  
Guodong Wu ◽  
Xinling Liu ◽  
Zongtao Zhang ◽  
...  
Keyword(s):  
High Performance ◽  
High Surface ◽  
High Surface Area ◽  
Three Dimensional ◽  
Formaldehyde Resin ◽  
Retention Performance ◽  
Competitive Strategies ◽  
Carbon And Nitrogen ◽  
N2 Atmosphere

Novel N-doped carbon nanonet flakes (NCNFs), consisting of three-dimensional interconnected carbon nanotube and penetrable mesopore channels were synthesized in the assistance of a hybrid catalytic template of silica-coated-linear polyethyleneimine (PEI). Resorcinol-formaldehyde resin and melamine were used as precursors for carbon and nitrogen, respectively, which were spontaneously formed on the silica-coated-PEI template and then annealed at 700 °C in a N2 atmosphere to be transformed into the hierarchical 3D N-doped carbon nanonetworks. The obtained NCNFs possess high surface area (946 m2 g−1), uniform pore size (2–5 nm), and excellent electron and ion conductivity, which were quite beneficial for electrochemical double-layered supercapacitors (EDLSs). The supercapacitor synthesized from NCNFs electrodes exhibited both extremely high capacitance (up to 613 F g−1 at 1 A g−1) and excellent long-term capacitance retention performance (96% capacitive retention after 20,000 cycles), which established the current processing among the most competitive strategies for the synthesis of high performance supercapacitors.

scholarly journals Porous cage-derived nanomaterial inks for direct and internal three-dimensional printing

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Tangi Aubert ◽  
Jen-Yu Huang ◽  
Kai Ma ◽  
Tobias Hanrath ◽  
Ulrich Wiesner
Keyword(s):  
3D Printing ◽  
Structural Control ◽  
High Surface ◽  
High Surface Area ◽  
Three Dimensional ◽  
Processing Technique ◽  
Advanced Materials ◽  
Host Matrix ◽  
Digital Light Processing ◽  
Three Dimensional Printing

Abstract The convergence of 3D printing techniques and nanomaterials is generating a compelling opportunity space to create advanced materials with multiscale structural control and hierarchical functionalities. While most nanoparticles consist of a dense material, less attention has been payed to 3D printing of nanoparticles with intrinsic porosity. Here, we combine ultrasmall (about 10 nm) silica nanocages with digital light processing technique for the direct 3D printing of hierarchically porous parts with arbitrary shapes, as well as tunable internal structures and high surface area. Thanks to the versatile and orthogonal cage surface modifications, we show how this approach can be applied for the implementation and positioning of functionalities throughout 3D printed objects. Furthermore, taking advantage of the internal porosity of the printed parts, an internal printing approach is proposed for the localized deposition of a guest material within a host matrix, enabling complex 3D material designs.

Three-Dimensional Cage Type Mesoporous CN-Based Hybrid Material with Very High Surface Area and Pore Volume

2007 ◽  
Vol 19 (17) ◽  
pp. 4367-4372 ◽  
Author(s):  
Ajayan Vinu ◽  
Pavuluri Srinivasu ◽  
Dhanashri P. Sawant ◽  
Toshiyuki Mori ◽  
Katsuhiko Ariga ◽  
...  
Keyword(s):  
Surface Area ◽  
Hybrid Material ◽  
Pore Volume ◽  
High Surface ◽  
High Surface Area ◽  
Three Dimensional ◽  
Very High

One-Step Synthesis of Nano-Size Iron Oxide /Three-Dimensional Wormlike Hierarchical Mesoporous SiO2 Catalysts and its Catalytic Performance on Phenol Hydroxylation

2013 ◽  
Vol 662 ◽  
pp. 202-206
Author(s):  
Jia Feng Wu ◽  
Yu Mei Zhao ◽  
Peng Liang
Keyword(s):  
Iron Oxide ◽  
High Surface ◽  
High Surface Area ◽  
Three Dimensional ◽  
Catalytic Performance ◽  
Phenol Hydroxylation ◽  
Weight Percentage ◽  
One Step ◽  
Hierarchical Pore ◽  
Nano Size

A series of nano-sized iron oxide supported on 3D wormlike hierarchical mesoporous SiO2 catalysts were synthesized by one-step hydrothermal synthesis. The samples were characterized by XRD, N2 sorption, FT-IR, UV–Vis, TEM and ICP-AES. The catalysts were probed for the oxidation of phenol employing hydrogen peroxide. The results indicate that the materials exhibit high surface area and 3D wormlike hierarchical pore, iron ions exist as isolated framework species when the weight percentage content of iron is below 0.24 and nano-size iron oxide is dispersed in the surface (iron content above 0.24 wt%). Catalytic performance indicates that nano-size iron oxide supported on SiO2 is useful to enhance both the catalytic activity and the selectivity of target products compared with isolated iron species.

Thermal Conductance of a Surface Phonon-Polariton Crystal Made up of Polar Nanorods

2017 ◽  
Vol 72 (2) ◽  
pp. 135-139 ◽  
Author(s):  
Jose Ordonez-Miranda ◽  
Karl Joulain ◽  
Younes Ezzahri
Keyword(s):  
Energy Transport ◽  
High Surface ◽  
High Surface Area ◽  
Three Dimensional ◽  
Thermal Conductance ◽  
Volume Ratio ◽  
Phonon Thermal Conductivity ◽  
Propagation Length ◽  
Surface Phonon ◽  
Surface Phonon Polariton

AbstractWe demonstrate that the energy transport of surface phonon-polaritons can be large enough to be observable in a crystal made up of a three-dimensional assembly of nanorods of silicon carbide. The ultralow phonon thermal conductivity of this nanostructure along with its high surface area-to-volume ratio allows the predominance of the polariton energy over that generated by phonons. The dispersion relation, propagation length, and thermal conductance of polaritons are numerically determined as functions of the radius and temperature of the nanorods. It is shown that the thermal conductance of a crystal with nanorods at 500 K and diameter (length) of 200 nm (20 μm) is 0.55 nW·K−1, which is comparable to the quantum of thermal conductance of polar nanowires.

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