Stainless Steel Foam Research Articles

Revolution of Electrode Design Toward Oxygen Evolution Reaction for Anion Exchange Membrane Water Electrolysis

Anion exchange membrane water electrolyzer (AEMWE) is a promising next-generation technology for producing green hydrogen coupling with cost-effective, platinum group metal-free (PGM-free) catalysts. In AEMWE, oxygen evolution reaction (OER) at the anode plays a more vital role compared with the cathodic reaction of hydrogen evolution reaction (HER). While tremendous attention has been devoted to enhancing the activity of OER catalysts, the long-term stability and cost of OER catalysts, which may play an even more important role in large-scale electrolysis industrialization, have been much less emphasized. Herein, we designed electrodes toward OER from cheap and abundant stainless-steel (SS) foam via a green approach, and the obtained electrode shows excellent activity and stability under an alkaline medium. This work can address all three bottlenecks of activity, stability, and cost, thereby revolutionizing the electrode design for AEMWE.

Efficient electrocatalytic nanocomposites of carbon nanotubes decorated with nickel selenides for urea oxidation reaction

In this study, carbon nanotubes (CNTs) coated with various phases of nanostructured nickel selenides were successfully synthesized with a simple and effective technique. These nanocomposites were then used as highly effective electrocatalysts for the urea oxidation reaction (UOR). The strategy involved depositing CNTs onto stainless steel (SS) foam using chemical vapor deposition, followed by pulse-reversal electrodeposition of nickel selenides in a layer-by-layer fabrication process. Different phases of nanostructured nickel selenides, such as NiSe2, NiSe2/Ni0.85Se, and Ni0.85Se, were successfully deposited on the surface of CNTs by controlling the reversal potential. Among all the different nanocomposites, the Ni0.85Se@CNTs-SS electrode exhibited the best electrocatalytic activity towards UOR. It required only a low overpotential, about 158 mV, to reach a benchmarking current density of 10 mA cm−2, and showed a low Tafel slope value of 85 mV dec−1. Additionally, the results of the prolonged stability study for 24 h confirmed the remarkable electrochemical stability of the Ni0.85Se@CNTs-SS electrode. After conducting stability studies, the overpotential shifted from 158 mV to 107 mV. This shift is due to the activation of the electrocatalyst during the stability test. The excellent electrocatalytic activity observed after the stability test is attributed to the presence of hydroxide and oxyhydroxide phases, which are remarkably active phases. This is the first-ever report where the Ni0.85Se@CNTs-SS nanocomposite electrode is shown to hold great potential as an effective electrocatalyst for UOR, which is an important step toward the design of a future electrocatalyst for UOR.

Experimental and numerical investigation of integrated system between cooled photovoltaic and wall-inserted PCM/FOM thermal energy storage box

Photovoltaic cooling has become important in order to reduce the operating temperature and increase the electrical generation, efficiency, and useable time. The extract heat produced by this cooling process could either be used immediately or stored for later use. In this study, many goals were examined through experimental and numerical investigation. They included the effect of cooling the photovoltaic panels and the potential to use the heat removed by the PV cooling system as well as how to store it in a thermal energy storage box (TESB). This box, made of paraffin wax as a phase change material and supported by stainless steel foam, has been installed into a test wall for heating at later time. The test wall was a component of an insulated test room that was linked to the cooling systems of the photovoltaic panel, to be the integrated system. According to the study, there is plenty of potential for storing the heat energy that the PV cooling system removes and using it later from the thermal energy storage box. After using the integrated system, the mean useful energy increased by 83% from 39.2 W for the uncooled PV panel to 71.7 W for the integrated system. The maximum PV electrical generated outputs for uncooled and water-cooled panels were 40.9 W and 43.3 W, respectively. The efficiency of uncooled and water cooled PV panels was 14.2% and 14.7%, respectively and dramatically increased to 25.9% for the integrated system.

Production and electrochemical properties of the sol–gel α-Al2O3 coated stainless steel foams

Production and electrochemical properties of the sol–gel α-Al2O3 coated stainless steel foams

Assessing the Surface Properties of Plant Extract-Based Silver Nanoparticle Coatings on 17–4 PH Stainless Steel Foams Using Artificial Intelligence-Supported RGB Analysis: A Comparative Study

Assessing the Surface Properties of Plant Extract-Based Silver Nanoparticle Coatings on 17–4 PH Stainless Steel Foams Using Artificial Intelligence-Supported RGB Analysis: A Comparative Study

Silver flowers decorated open cell stainless steel foam for bone scaffold application

Silver flowers decorated open cell stainless steel foam for bone scaffold application

The Microstructure and the Properties of 304 and 430 Steel Foams Prepared by Powder Metallurgy Using CaCl2 as a Space Holder

In order to prepare stainless steel foams (SSFs) with high specific strength, cost-effective performance, and multiple relative density ranges, this work used CaCl2 as a space holder to prepare 304 and 430 SSF samples with different relative densities using the powder metallurgy method. The microstructure and the properties were compared and analyzed by optical microscope (OM), scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD), and a universal testing machine. The results show that the matrix of 304 SSFs is austenite and 430 is ferrite. In the quasi-static compression test, when the relative density was in the range of 0.33~0.12, their compressive strength increased with the relative density increasing; the maximum compressive strength of 304 SSFs reached 40.29 MPa and that of 430 SSFs was 49.79 MPa. While the compressive strength of 430 SSFs is significantly higher than 304 SSFs at a similar relative density, 304 SSFs show better stability in the plastic deformation stage. When the deformation reached densification, the maximum energy absorption value of 304 SSFs reached 15.94 MJ/m3, while 430 SSFs was 22.70 MJ/m3. The energy absorption value increased with the relative density increasing, and 430 SSFs exhibited a higher energy absorption capacity than 304 SSFs.

In situ Growth of Ni(OH)2 Nanoparticles on 316L Stainless Steel Foam: An Efficient Three‐dimensional Non‐enzymatic Glucose Electrochemical Sensor in Real Human Blood Serum Samples

AbstractFor the first time, nickel hydroxide nanoparticles (Ni(OH)2 NPs) grown on 316L stainless steel foam were used as a non‐enzymatic electrochemical glucose sensor. The Ni(OH)2/SSF‐316L was elaborated by applying a simple ultrafast CV method without nickel salts addition. Ni(OH)2/SSF‐316L was characterized by SEM and XRD. The electrochemical behavior was investigated by CV, EIS, and amperometric measurements. The fabricated sensor revealed higher sensitivity 1062 μA mM−1cm−2, wide linear range from 1.0 μM to 4.0 mM with a low detection limit of 2.0 μM and good selectivity. In addition, real sample analysis was performed for controlled glucose in real blood serum.

Stainless steel foam as wick material in heat pipe for electronics cooling application

In this preliminary investigation, we analyzed the possibility using a stainless steel foam as a wick material in heat pipe. The heat pipe will be used as a passive cooling sytem in electronic devices. Stainless steel foam that used in the current investigation is a commercial foam that has been treated to be characterized using SEM and 3D optical microscope. Analytical models were also developed to calculate the capillary pressure and effective thermal conductivity of the stainless steel foam. The analytical model revealed that the optimum stainless steel foam to be used as wick material is found at the pore size, porosity and contact angle of 30 μm, 0.1 and 0°, respectively.

Air permeability and tensile properties of novel micron-scale gradient porous plates fabricated by rolling and vacuum sintering

A new type of gradient porous plate (GPP) was successfully fabricated by rolling and vacuum sintering using powders and wire mesh porous plates (WMPPs). The air permeability and tensile strength tests were carried out and the fracture morphology was observed. The results showed that the GPPs with low porosity not only had micron-pore structure with the pore size below 10 μm, and air permeability reached 1.27 × 10−13 m2, but also hold tensile strength with 257.8 MPa. Particularly, its air permeability and tensile strength were significantly superior to nuclear graphite, stainless steel foam, and porous alumina ceramics, equivalent to porous titanium. This study provides an effective method for the fabrication of micron-scale metal GPPs, and is of great significance for expanding the application range (especially in the fields of micron-scale precision filtration and the porous throttles of the aerostatic bearing) of porous materials.

Study on enhanced heat transfer characteristics of metal foam solar receiver in Solar Power Tower plants

In order to explore the mechanism of heat and mass transfer of metal foam absorber based on electrodeposition, the numerical simulation study of metal foam absorbers with different structures was carried out, and the heat transfer model of the coated metal foam tube bundle with a tube spacing of 3D × 1.5D was analyzed and established. Compared with the smooth tube bundle, with the Re number varying from 100 to 1500, the Rext of the tube bundle coated with stainless steel foam decreased from 0.061 K/W to 0.009 K/W, and the thermal resistance ratio outside the tube increased from 2.75 to 4.76. The pressure loss of the tube rose from 1.89 Pa to 80.10 Pa, and the pressure loss outside the tube dropped from 5.15 to 3.12. The overall performance index PEC of the tube increased from 1.59 to 3.26. Compared with rows of staggered tube bundles from 2.5D to 2.2D, the heat transfer coefficient can reach 4621 W/m2/K and the pressure loss is 1.67%.

In-Pile Performance of TRISO Particle Used Stainless Steel Foams as Buffer Layer

Thermal conductivity of TRISO particle deteriorated during in-pile operation due to the shrinkage of the low density carbon buffer layer and the gap appeared. In order to solve this problem, stainless steel foam was used to replace the low density carbon buffer layer as buffer layer in TRISO particle. The in-pile performance of the new type TRISO particle was simulated, and the result indicated that the stainless steel foam can avoid the gap between the buffer and the IPyC layer which can increase the thermal conductivity and decrease the kernel temperature during operation process; at the same time, regardless of stainless steel foam or low density carbon buffer layer used as buffer layer, the stress on IPyC and OPyC layers all exceeded the strength of the two layers. Hoop stress on SiC layer decreased with the elasticity modulus of metal foam, and the stress can be controlled by decreasing the elasticity modulus. To sum up, metal foam with high porosity and low elasticity modulus can be selected as the buffer layer to improve the thermal conductivity and assure the integrity of the coated layer and increase the life time. This study offered the optimization direction of TRISO particle for engineering application.

Electrochemical treatment of dye wastewater using nickel foam electrode

Removal of dye from wastewater has been investigated using the electrocoagulation method. Batch experiment has been conducted to remove the color from synthetically prepared acid red 87dye wastewater. Stainless steel and nickel foam sheets are used as cathode and anode, respectively. The effect of some operating parameters, such as current density, initial dye concentration and supporting electrolyte concentration, on color removal has been studied. It can be observed from the present investigations that the nickel foam electrode effectively removes color from the wastewater. Nickel hydroxyl species formed during the operation and also, nickel (II) hydroxide flocs formed in a subsequent stage, trap colloidal precipitates and make solid-liquid separation easier during the flotation stage. These stages of electrocoagulation must be optimized to design an economically feasible process.

Effect of particle shape on microstructure and compressive response of 316L SS foam by space holder technique

316 L stainless steel (SS) foams with varying porosities have been developed through PM route using irregular and spherical particles shaped SS powder using urea as space holder. The effect of SS particle shape on microstructure and compressive deformation behaviour of SS foams with varied relative density were studied. The cell size and the cell wall thickness in the foam produced by both types of shapes are comparable. The yield stress, elastic modulus, plateau stress, plastic modulus, micro-hardness and energy absorption values are higher in the foam made through irregular particle shape as compared to spherical one inspite of slightly lesser relative densities. This is due to presence of higher micro-porosities in the cell wall in the foam produced by spherical particles. Therefore, the densification strain is slightly higher in SS foam made with spherical particles. The presence of fewer contacts between spherical powders led to lesser densification in the cell wall region and thus higher micro-porosity evolved. The yield stress, elastic modulus, plateau stress (σpl), plastic modulus and energy absorption (Eab) follow power-law relationship irrespective of SS powder particle shapes. However densification strain follows linear relationship.

Cost-effective polymetallic selenides derived from stainless steel foam (SSF) for overall water splitting

Cost-effective polymetallic selenides derived from stainless steel foam (SSF) for overall water splitting

Preparation, characterization and evaluation of a novel CMC/Chitosan-α-Fe2O3 nanoparticles-coated 17–4 PH stainless-steel foam

In this study, we fabricated a novel CMC/Chitosan-α-Fe2O3 nanoparticles (NPs)-coated 17–4 PH stainless-steel foam. The CMC/Chitosan matrix was preferred as a stabilizing role in the uniform dispersion of α-Fe2O3 NPs in the colloidal solution. The BET, SEM/EDX, XRD, and FT-IR techniques were used to determine the functional groups and surface of the nanostructure. The α-Fe2O3 NPs were uniformly dispersed and had a spherical shape with an average particle size of 10–20 nm with a surface area of 180.37 m2/g. Additionally, we examined to identify the physicochemical properties of the α-Fe2O3 NPs under ultrasonic irradiation. According to SEM results, we found that the average particle size of CMC/Chitosan-α-Fe2O3 NPs was between 10 and 20 nm with a spherical shape. We observed the effects of the operating parameters such as the concentration (0–1 ppm), mass fraction (10–20%) of silica, mass fraction (1–5%) of CTAB, temperature (25–45 °C), pH (3–10), sonication time (5–20 min), and the amplitude of sonication (10–40%). A mathematical modeling was performed, which related surface tension via the operating variables. The critical micelle concentrations were found 0.399, 0.428, and 0.573 ppm for mass fractions 10, 15, and 20% of silica, respectively. An error analysis was conducted in order to evaluate the physicochemical properties of the constructed models. Results showed that the effect of ultrasonic irradiation on the surface tension of biopolymer blend based α-Fe2O3 NPs and the design of uniform stainless-steel foam with α-Fe2O3 NPs coatings.

Fabrication of 17‐4PH Stainless Steel Foam by a Pressureless Powder Space Holder Technique

High compressive strength closed‐cell porous 17‐4PH precipitation hardening stainless steel with three different porosities (30%, 40%, and 50%, volume percent) was manufactured using a novel pressureless powder space holder method. The compressive strengths of the as‐sintered 17‐4PH stainless steel foam with porosities of 30%, 40%, and 50% are 420, 275, and 187 MPa, respectively. The application of an H900 heat treatment to the as‐sintered porous 17‐4PH stainless steel can effectively improve the compressive strength due to the precipitation of ϵ‐Cu phases. It is shown that with this pressureless powder space holder method, it can efficiently produce closed‐cell porous 17‐4PH stainless steel and control its porosity.

Performance of AISI 316L-stainless steel foams towards the formation of graphene related nanomaterials by catalytic decomposition of methane at high temperature

This work explores the preparation of graphene-related materials (GRMs) grown on stainless steel foams via catalytic decomposition of methane (CDM). The main active phases for the reaction are the Fe nanoparticles segregated from the stainless-steel after the activation stage of the foam. The effect of the feed composition and reaction temperature has been studied in order to maximize the productivity, stability and selectivity to GRMs. The maximum productivity attained was 0.116 gC/gfoam h operating at 950 °C with a feed ratio of CH4/H2 = 3 (42.9 %CH4:14.3 %H2). The carbonaceous nanomaterials (CNMs) obtained were characterized by X-Ray diffraction, Raman spectroscopy and by transmission and scanning electron microscopy. The parameters of the kinetic model developed are directly related to the relevant stages of the process, including carburization, diffusion-precipitation and deactivation-regeneration. The balance among these sequential stages determines the overall performance of the activated foam. In conditions of rapid carburization of the Fe NPs (pCH4 > 14 %), the productivity to CNMs is favoured, avoiding an initial deactivation of the active sites by fouling with amorphous carbon. After a rapid carburization, the selectivity to the different CNMs is governed by the ratio CH4/H2, and mainly by the temperature. Thus, the formation of GRMs, mainly Few Layer Graphene (FLG) and even graphene, is favoured at temperatures above 900 °C. At lower temperatures, carbon nanotubes are formed.

Effect of compressive strain rate on the deformation behaviour of austenitic stainless steel foam produced by space holder technique

316L austenitic stainless steel foam (ASSF) with 55–81% porosities was made by P/M route using urea as space holder. The cold compacted at 500 MPa pressure and sintered at 1200 °C for 60 min. Microstructure, cell size, cell walls thickness and micro-hardness were evaluated. Twins boundaries are visible in cell wall regions. XRD, FESEM, and EDX analysis proved that no residue of space holder particles remained in the sintered foam samples. The compressive deformation behaviour of sintered foam samples are studied under three different strain rate (0.001, 0.01, and 0.1 s−1). The yield stress (σy), average plateaus stress (σpl), elastic modulus (Ef) and energy absorption (Eab) increases with increase in relative density (ρrd), and also increased with increasing strain rate. Densification strain decreased with increasing strain rate and follows linear relationship with ρrd. The yield stress, elastic modulus, and densification strain were compared with Gibson-Ashby's model and are found to be in closed agreement. The stain rate parameter (Σ) marginally decreases with increase in ρrd and follows linear relationship with ρrd.

Visible-Light Photocatalytic Degradation of Aniline Blue by Stainless-Steel Foam Coated with TiO2 Grafted with Anthocyanins from a Maqui-Blackberry System

Anthocyanins from maqui (Aristotelia chilensis) and blackberry (Rubus glaucus) were used as light harvesters to improve the photocatalytic activity of titanium dioxide in visible light. Anthocyanins from both species were obtained using high-frequency ultrasound-assisted liquid-liquid extraction with methanol. Mixtures of anthocyanins were developed to study their effectiveness in the visible light/TiO2 reaction for the oxidation of aniline blue. For this purpose, stainless-steel foams were covered with TiO2 and anthocyanin and characterized by SEM. Different samples were fabricated by varying the ratio of the two anthocyanins in the mixture (100, 75, 50, 25 and 0 vol% of maqui-anthocyanin (delphinidin)). The mixtures of 25 vol% anthocyanin from maqui and 75 vol% anthocyanin from blackberry had higher total anthocyanin content and better photocatalytic activity in visible light: degradation of aniline blue was 40% at pH 7, 56% at pH 3 and 95% at pH 3 with the injection of oxygen for 2 h in comparison with TiO2-foam/UV light, which yielded values of 13% at pH 7 and 73% at pH 3 with and without the addition of oxygen. Natural dyes that are low-cost and environmentally friendly substances are shown to be capable of improving the visible-light photocatalytic activity of TiO2.