Dynamic Hydrogen Bubble Research Articles

Nanoporous Gold-Modified Screen-Printed Electrodes for the Simultaneous Determination of Pb2+ and Cu2+ in Water.

In this study, nanoporous gold (NPG) was deposited on a screen-printed carbon electrode (SPCE) by the dynamic hydrogen bubble template (DHBT) method to prepare an electrochemical sensor for the simultaneous determination of Pb2+ and Cu2+ by square wave anodic stripping voltammetry (SWASV). The electrodeposition potential and electrodeposition time for NPG/SPCE preparation were investigated thoroughly. Scanning electron microscopy (SEM) and energy-dispersive X-ray diffraction (EDX) analysis confirmed successful fabrication of the NPG-modified electrode. Electrochemical characterization exhibits its superior electron transfer ability compared with bare and nanogold-modified electrodes. After a comprehensive optimization, Pb2+ and Cu2+ were simultaneously determined with linear range of 1-100 μg/L for Pb2+ and 10-100 μg/L for Cu2+, respectively. The limits of detection were determined to be 0.4 μg/L and 5.4 μg/L for Pb2+ and Cu2+, respectively. This method offers a broad linear detection range, a low detection limit, and good reliability for heavy metal determination in drinking water. These results suggest that NPG/SPCE holds great promise in environmental and food applications.

Leaded Bronze Foams As Innovative Electrodes for Organic Electrosynthesis

The electrification of organic synthesis represents an outstanding green alternative to prepare valuable and fine chemicals. However, the design of electrode materials for organic electrosynthesis remains as an open field to investigate. Motivated by the superior performance of leaded bronzes as electrodes for reductive transformations,[1, 2, 3] we have developed highly porous binary and ternary leaded metal foams through the dynamic hydrogen bubble template method [4] and tested them as cathodes in the electro-organic synthesis of 2,6-dichlorobenzonitrile from 2,6-dichlorobenzaldoxime.[5]The electrocatalytic performance of the novel leaded foams was compared to the one of the planar CuSn7Pb15 leaded bronze. The novel porous leaded foams outperformed the CuSn7Pb15 electrodes in terms of chemical yield and energy efficiency. Furthermore, due to their highly crystalline surface, these materials are mechanically more stable and less prone to cathodic corrosion than flat Pb and CuSn7Pb15 electrodes.

Preparation of Porous Ni-W Alloys Electrodeposited by Dynamic Hydrogen Bubble Template and Their Alkaline HER Properties

Nickel–tungsten (Ni-W) alloys are gaining significant attention due to their superior hardness, wear resistance, anti-corrosion and electrochemical hydrogen evolution reaction (HER) activity. In this work, porous and crack Ni-W alloys with different W contents were prepared in a pyrophosphate bath. The key to forming a porous structure is a very high current density over 300 mA cm−2. The HER activity of porous and crack Ni-W alloys was studied by means of electrochemical technologies of linear sweep voltammetry (LSV), Tafel curves (Taf) and electrochemical impedance spectroscopy (EIS). Compared with the crack Ni-W alloy, the porous Ni-W alloy exhibits improved alkaline electrochemical HER performances, which can deliver a current density of 10 mA cm−2 at 166 mV (η10) vs. RHE (reversible hydrogen electrode).

3D Nickel–Manganese bimetallic electrocatalysts for an enhanced hydrogen evolution reaction performance in simulated seawater/alkaline natural seawater

In this paper, we report an inexpensive one-step synthesis of self-supported 3D nickel-manganese (NiMn) bimetallic coatings and their application for the hydrogen evolution reaction in simulated seawater (1 M KOH + 0.5 M NaCl) and alkaline natural seawater (1 M KOH + natural seawater). These binary coatings were electrodeposited on a titanium substrate using a facile electrochemical deposition method by a dynamic hydrogen bubble template technique. The as-deposited NiMn coatings with variable Mn amounts produce typical globular and unique porous architecture with abundant pores of different sizes. The activity of these fabricated catalysts towards the hydrogen evolution reaction was investigated by linear sweep voltammetry towards simulated seawater and alkaline natural seawater at different temperatures. The surface morphology and composition of the catalysts were also characterized by scanning electron microscopy and inductively coupled plasma optical emission spectroscopy. The as-prepared NiMn/Ti electrocatalyst, which was electrodeposited using a chemical bath containing Ni2+ and Mn2+ ions with a molar ratio of Ni2+:Mn2+ = 1:5, exhibits excellent hydrogen evolution activity in simulated seawater with an ultra-low overpotential of 64.2 mV to reach a current density of 10 mA cm−2. It is noteworthy that this NiMn/Ti electrocatalyst also achieves a current density of 10 mA cm−2 in alkaline natural seawater with a comparably low overpotential of 79.3 mV. The current densities increase by ca. 1.75–2.35 times with an increase in temperature from 25 °C to 75 °C for hydrogen evolution in both electrolytes. This bimetallic catalyst has shown excellent long-term stability at a constant potential of −0.23 V (vs. RHE) and a constant current density of 10 mA cm−2 for 10 h, which ensures higher durability and robustness for practical application of seawater splitting technology.

Tailoring the Active Sites of Nanosheet NiSe/NiSe2 Catalyst by Pulse Electrodeposition on the 3D Microporous Ni-Cu/NF Substrate for both Hydrogen and Oxygen Evolution Reactions

Establishing proper intrinsic catalysts with nanostructured high active surfaces endows the paramount electrocatalytic activity. A Ni-Se@Cu-Ni/NF catalyst for hydrogen and oxygen evolution reactions (HER and OER) is prepared via an efficient two-step pulse current (PC) electrodeposition method. The initial 3D film of Cu-Ni is synthesized via the dynamic hydrogen bubble template (DHBT) method to attain further active surface area. Then, Ni-Se film is prepared by direct current (DC) and PC electrodeposition. Morphological, chemical, and electrocatalytic characteristics of the Ni-Se electrodeposited films are evaluated. X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy results show a NiSe/NiSe2 nanofilm on the 3D microporous nanostructured Cu-Ni substrate which reveals an efficient bifunctional electrocatalytic behavior with overpotentials of 74 and 272 mV in the current density of 10 mA cm−2, and Tafel slopes of 78 and 50 mV dec−1 for HER and OER, respectively. The two-electrode examination with NiSe/NiSe2@Cu-Ni/NF catalyst in overall water splitting indicates a required potential of 1.57 V in the current density of 10 mA cm−2.

Nanoengineered Cobalt Electrocatalyst for Alkaline Oxygen Evolution Reaction.

The alkaline oxygen evolution reaction (OER) remains a bottleneck in green hydrogen production owing to its slow reaction kinetics and low catalytic efficiencies of earth abundant electrocatalysts in the alkaline OER reaction. This study investigates the OER performance of hierarchically porous cobalt electrocatalysts synthesized using the dynamic hydrogen bubble templating (DHBT) method. Characterization studies revealed that electrocatalysts synthesized under optimized conditions using the DHBT method consisted of cobalt nanosheets, and hierarchical porosity with macropores distributed in a honeycomb network and mesopores distributed between cobalt nanosheets. Moreover, X-ray photoelectron spectroscopy studies revealed the presence of Co(OH)2 as the predominant surface cobalt species while Raman studies revealed the presence of the cubic Co3O4 phase in the synthesized electrocatalysts. The best performing electrocatalyst required only 360 mV of overpotential to initiate a current density of 10 mA cm-2, exhibited a Tafel slope of 37 mV dec-1, and stable OER activity over 24 h. The DHBT method offers a facile, low cost and rapid synthesis approach for preparation for highly efficient cobalt electrocatalysts.

Nitrous acid electroreduction on macroporous silver foam

In this paper, silver 3D foams have been synthesized using dynamic hydrogen bubble template and thiocyanate-based deposition bath. The material was used as electrocatalyst for nitrous acid (HNO2) reduction. On this material, we found that overpotential of nitrous acid reduction is decreased by at least 300 mV and the in situ formed nitric oxide (NO) reduction becomes the predominant step when the potential is decreased even further, comparing to flat silver polycrystalline electrode. Another difference between this material and the silver polycrystalline electrode concerns the influence of the nature of supporting electrolyte on the preferred reaction. Precisely, while Ag polycrystalline is preferentially reducing HNO2 into NO in low concentration of perchlorate electrolyte, Ag foam preferentially reduces the in situ formed NO into N2O, in all tested electrolytes, if the same potential range is considered. The initial reduction of HNO2 into NO is better evidenced after the partial removal of thiocyanate species. Finally, the use of isotope 15N in the nitrite salt and of a flow thin layer cell enabled the detection of nitrogen among other gaseous products for both silver foam and flat silver electrode.

Achieving Long Cycle Life of Zn-Ion Batteries through Three-Dimensional Copper Foam.

Metallic zinc anodes in aqueous zinc-ion batteries (ZIBs) suffer from dendritic growth, low Coulombic efficiency, and high polarization during cycling. To mitigate these challenges, current collectors based on three-dimensional (3D) commercial copper foam (CCuF) are generally preferred. However, their utilization is constrained by their thickness, low electroactive surface area, and increased manufacturing expenses. In this study, the synthesis of cost-effective current collectors with exceptionally large surface areas designed for ZIBs that can be cycled hundreds of times is reported. A zinc-coated CuF anode (Zn/CuF) was prepared with a 3D porous CuF current collector produced by the dynamic hydrogen bubble template (DHBT) method. Electrochemically generated copper foam could be obtained within seconds while offering a thickness as low as 30-40 μm (CuF5 achieved a thickness of ∼38 μm in 5 s) via the DHBT method. The excellent electrical conductivity and open pore structure of the 3D porous copper scaffold ensured the uniform deposition/stripping of Zn during cycling. During the 500 h Zn deposition/stripping process, the as-synthesized CuF5 current collector offered fast electrochemical kinetics and low polarization as well as a relatively high average Coulombic efficiency of 99% (at a current density of 5 mA cm-2 and a capacity of 1 mAh cm-2). Furthermore, the symmetric cell exhibited low voltage polarization and a stable voltage profile for 1000 h at a current density of 0.1 mA cm-2. In addition, full cells containing the Zn/CuF anode coupled with an as-synthesized α-MnO2 nanoneedle cathode in aqueous electrolyte were also prepared. Capacities of 266 mAh g-1 at 0.1 A g-1 and 94 mAh g-1 at 2 A g-1 were achieved after 200 charge/discharge cycles with a stable Coulombic efficiency value close to 99.9%.

Manufacturing Free‐Standing, Porous Metallic Layers with Dynamic Hydrogen Bubble Templating

AbstractThe 3D structure (i.e., microstructure) of porous electrodes governs the performance of emerging electrochemical technologies such as fuel cells, electrolysis, and batteries. Sustaining electrochemical reactions and convective‐diffusive mass transport at high efficiency is complex and motivates the search for sophisticated microstructures with multimodal pore size distributions and pore size gradients. Here a new synthesis route for porous, metallic layers is presented that combines the characteristics of carbon structures (i.e., pore size, porosity) with the properties of metals (i.e., recyclability, conductivity). Building on the method of dynamic hydrogen bubble templating, a novel approach is engineered to manufacture thin, free‐standing layers using an electrochemical flow cell through the introduction of an intermediate layer and optimization of the synthesis parameters. Mechanically stable layers are created with thicknesses ranging from ≈50 to ≈200 µm comprising porous, dendritic structures, arranged to form a vascular network of larger pores with a gradient in radii from ≈5 µm at the bottom and up to ≈36 µm at the top of the material. Using X‐ray tomographic data, the morphology is analyzed, and the diffusive transport through the material as a function of liquid filling is simulated and compared to state‐of‐the‐art carbon fiber‐based electrodes, showing significantly higher mass transfer properties.

In situ fabrication of transition metal phosphide tree-like nanostructure for energy-saving hydrogen production coupled via urea oxidation reaction

Substituting the Oxygen Evolution Reaction (OER) with the Urea Oxidation Reaction (UOR) which is a thermodynamically more favorable option, has paved the way for the production of energy-saving hydrogen as well as the purification of urea-reach waste water. In this study, a nanostructured, porous and active Ni-Cu-Mn-P electrode was created using the dynamic hydrogen bubble template (DHBT) process in different conditions. The fabricated electrodes were utilized as bi-functional electrodes for both the HER and UOR processes. The electrochemical results displayed that the Ni-Cu-Mn-P (which synthesized at current density of 2 A.cm−2) requires only 84 mV overpotential to achieve a current density of 10 mA.cm−2, in HER process, and the necessary potential value for the UOR is only 1.30 V vs RHE. Also, the favorable electrocatalytic stability for industrial applications was also confirmed. The Ni-Cu-Mn-P electrode also demonstrated satisfactory performance in the overall urea electrolysis process and the cell voltage was 1.40 V to generate 10 mA.cm−2. The excellent performance of the electrode was due to the hierarchical porous nanostructure with high active surface area and also the synergistic effect between the elements. This study introduces an effective catalyst design for energy-saving hydrogen production.

Performance enhanced Ti-based thin film getter with porous nickel as scaffold

n order to meet the requirement of high vacuum in MEMS devices, an improved Ti-based thin film getter with porous nickel scaffold was prepared by using dynamic hydrogen bubble template (DHBT) method, which finally effectively increased the specific surface area (SSA) and improved the adsorption performance. The microstructure and adsorption performance of the getter were studied by scanning electron microscope, BET, thermogravimetric analysis (TGA) and hydrogen adsorption test. The results show that the SSA of the prepared porous nickel scaffold can reach up to 11.622 m2/g. The aspect ratio of mesopores is around 2. The Ti film deposited on the scaffold have a good coating effect on the porous structure and have little effect on the aspect ratio. When the deposition thickness is 300 nm, the adsorption capacity (3.51374 mg) and adsorption rate (6.507 × 10−4mg/(s∙g)) can reach the highest. Hydrogen adsorption tests also show that the Ti-based thin film getter with porous nickel scaffold has a good repeatability, and its average initial adsorption rate reaches 8.195ml/(s∙cm2), which is nearly an order of magnitude higher than that of the two-dimensional planar getter.

One‐step synthesis of ultra‐small amount of Pd‐Alloyed Zinc Nanosheets for efficient electrochemical CO2 reduction to CO

AbstractThe practicality of the electrochemical CO2 reduction technique depends on the development of cost‐effective, robust, and highly selective catalysts. To achieve this goal, we have engineered self‐supported 3D electrodes composed of Pd‐Zn nanosheets (NSs) for CO2 electrochemical reduction to CO with minimal Pd content. This innovative electrode with an increased surface area was created using an electrodeposition method employing a dynamic hydrogen bubble template. By precisely adjusting the Pd content, we improved the thickness, porosity, and surface area of the electrodes, resulting in a CO2‐to‐CO selectivity reaching as high as 88.5 %, with an average of at least 80 % sustained over 10 hours. This remarkable improved activity can be attributed to the synergistic effects of an appropriate Pd/Zn atomic ratio as well as to the large surface area of nanosheets structures with rich edge active sites. Furthermore, to get around the limitations of CO2 mass transfer, reactions were done at high pressures conditions ranging from 3 to 9.5 bar; this strategic approach yielded an outstanding partial current density of −304.6 mA cm−2 for CO. These noteworthy findings establish concepts for constructing effective and earth‐abundant CO‐producing electrocatalysts.

Effective Energy Storage Performance Derived from 3D Porous Dendrimer Architecture Metal Phosphides//Metal Nitride-Sulfides.

The present work addresses the limitations by fabricating a wide range of negative electrodes, including metal nitrides/sulfides on a 3D bimetallic conductive porous network (3D-Ni and 3D-NiCo) via a dynamic hydrogen bubble template (DHBT) method followed by vapour phase growth (VPG) process. Among the prepared negative electrodes, the 3D-Fe3S4-Fe4N/NiCo nanostructure demonstrates an impressive specificcapacitance (Cs) of 1125 F g-1 (2475 mF cm-2) at 1 A g-1 with 80% capacitance retention over 5000 cycles. Similarly, a 3D-Mn3P nanostructured positive electrode fabricated via electrodeposition followed by a phosphorization process exhibits a maximum specific capacity (Cg) of 923.04 C g-1 (1846.08 mF cm-2) at 1 A g-1 with 80% stability. A 3D-Mn3P/Ni//3D-Fe3S4-Fe4N/NiCo supercapattery is also assembled, and it shows a notable CS of 151 F g-1 at 1 A g-1, as well as a high energy density (ED) of 51Wh kg-1,a power density (PD) of 782.57W kg-1 and a capacitance efficiency of 76% over 10000 cycles. This may be ascribed to the use of a bimetallic 3D porous conductive template and the attachment of transition metal sulfide and nitride. The development of negative electrodes and supercapattery devices is greatly aided by this exploration of novel synthesis techniques and material choice.

Modulation of active surface sites on Ni–Fe–S by the dynamic hydrogen bubble template method for energy-saving hydrogen production

A porous structure was electrosynthesized via a DHBT with interconnected nanosheets. The fabricated electrode demonstrated great activity for the UOR and HER.

Thermal Efficiency Evaluation after Thermocompression of Copper Layer Obtained By Dynamic Hydrogen Bubble

With the increase in engines electrification, especially in aircraft future developments, there is a need of extremely high-power converters in the power electric chain, interfacing the electrical network and the electric motors. The COPPERPACK project (COPPER based PACKaging for direct cooled power module ANR-19-CE05-0011) aims to module assembling by thermocompression, which requests the elaboration of thin nanoporous copper films to be placed between chips and metallized ceramic substrates. Different possibilities exist and have been tested all along the project, such as copper-zinc or copper-manganese electrodeposition followed by an anodic dissolution, but the faster and simpler way resides in electroforming deposition made by Dynamic Hydrogen Bubble Template (DHBT) [1]. This process works in unusual potentials and current densities where the competition between hydrogen discharge (commonly avoided) and copper reduction is very high. In this case, this method achieves thick deposits in very short time (few seconds) with high currents allowing a very fast growth of copper around hydrogen bubbles. Pores and ligaments sizes can be controlled by several operating parameters i.e. current densities, temperature, deposit time, chemical additives [2] as well by pulsed currents. Films were tested for chips assembling by thermocompression, and present excellent behavior’s. Several conditions have been tested, in different configurations, varying the size and the height of the chips.Eventually, this system has been extended to cooling systems, favoring the assembling of copper foams and complex copper shapes, designed for cooling fluid circulation. Once again, the copper layers obtained by DHBT allow to build compact and efficient systems.[1] Abdel-Karim, R.; El-Raghy, S. Chap 4 in Advanced materials and their applications - micro to nano scale. One Central Press, United Kingdom, pp 69–91, 2017[2] Shin, H.-C.; Liu, M. Chem. Mater. 2004, 16, 25, 5460–5464 doi.org/10.1021/cm048887b

Breaking Free - Unlocking the Potential of Dynamic Hydrogen Bubble Templating Materials

In recent years, porous electrodes for electrochemical conversion devices, such as low-temperature fuel cells or water electrolyzers, have been engineered to address issues related to mass transport to and within the catalyst. For example, the addition of a layer with reduced pore size facing the catalyst layer (i.e., microporous layer) results in an increased performance[1–3]. Furthermore, chemical[4], as well as mechanical[5,6]. methods of creating dedicated liquid and gas pathways in the porous electrodes, have been investigated with promising results, highlighting the need for further optimization of state-of-the-art materials with regards to multi-phase transport. The range of possible modifications is intrinsically limited by the microstructure of the material they are applied to and add cost and complexity to the already costly electrode production procedure, motivating the development of novel materials which contain these desired features, offer a large morphological design space, and are cost competitive.To tackle these stringent targets, we investigate the dynamic hydrogen bubble templating (DHBT) method to generate hierarchical structures containing both a pore size gradient as well as dedicated water and gas pathways in the form of bimodal pore size distributions. It leverages simultaneous deposition of a metal and gas evolution on the same surface to form complex structures from solution using electricity. It results in a hierarchical structure of primary pores (~5-40 µm) separated by porous walls containing secondary pores (10-1000 nm) . This type of material has been used successfully to improve boiling heat transfer[7], another process limited by the counterflow of liquid and gas. They have also been investigated as high surface area material for microbial anodes[8] and have been postulated to be appealing in other electrochemical devices such as batteries or fuel cells[9]. A significant hurdle to unlock the full potential of DHBT foams is the attachment of the foam to the solid electrode surface it is generated on. The presence of the electrode blocks the transport of media in the through-plane direction of the foam and thereby prevents its use in many electrochemical applications. Due to its fragile nature, separation of the foam from this surface easily damages the structure, which is why previous research was done exclusively in the presence of the electrode. Overcoming this limitation would enable new applications for DHBT foams and has the potential to address a wide range of problems in electrochemical systems related to porous media.In this talk, I will discuss our work towards creating free-standing, hierarchically structured metal electrodes through DHBT and the developments needed to adapt this material for the use in electrochemical systems. Owing to its well-studied synthetic parameters and facile electrodeposition, we chose copper foams to advance DHBT materials in terms of characterization and mechanical properties. As a key step of the synthesis route, we realized a method to manufacture free-standing sheets from this material from copper metal while preserving its delicate microstructure. This was supported by an optimization of synthesis parameters to improve and ensure adequate mechanical stability of the freestanding foams after isolation. This development enables the application of a wide range of characterization methods such as XTM, BET, SEM and interferometry and I will discuss how the synthesis parameters link to the resulting material microstructure. Building on this initial success, current work focuses on the transferring this knowledge to the synthesis of foams made from other metals which are more relevant to electrochemical applications such as nickel for the use in alkaline electrolyzers and paves the way to develop DHBT material into the next generation transport layer for electrochemical systems.

Dynamically assisted electrodeposition by hydrogen bubbles on carbonized wood: A NiFeCo nanoflower electrocatalyst for efficient hydrogen evolution

The development of cost-effective, simple, and highly active catalysts for electrochemical water splitting in alkaline electrolytes to produce renewable source H2 is critical to solve the environmental pollution and energy crisis. In this study, a series of nanoflower-like NiFeCo/CW catalytic electrodes were prepared by a facile one-step dynamic hydrogen bubble template (DHBT) method for electrodeposition on carbonized wood (CW), which have excellent HER performance. By reasonably investigating the effects of H+ concentration and time, a catalyst with ideal deposition results was obtained. In 1 M KOH solution, the prepared NiFeCo/CW-450 catalyst exhibits a small overpotential of 37 mV to achieve a current density of 10 mA cm−2, and still possess a satisfactory low overpotential when a larger current density is reached (η400 = 238 mV, η1000 = 298 mV). Furthermore, NiFeCo/CW can keep structure and catalytic performance stable after long-term test. The remarkable HER performance results from the unique nanoflower electrode structure that is uniformly dispersed on CW to fully expose the active site. As a result, this work will provide new inspiration and strategy for the preparation of novel simple, inexpensive and efficient electrocatalytic hydrogen evolution electrodes using earth-abundant resources.

Ultra-fast electrodeposition of dynamic hydrogen bubble template nickel sulfide on a porous copper layer as an electrocatalyst toward hydrogen evolution reaction

Finding cost-effective electrocatalysts that can match the performance of noble metals like platinum is crucial for renewable hydrogen energy generation. In this study, the electrocatalytic properties of a nickel sulfide compound deposited on a porous copper network that is formed on a nickel foam substrate are investigated. To achieve this goal, the dynamic hydrogen bubble template method was employed. Copper and nickel sulfide electrodeposited in 5 s at 6 A cm−2. The presence of the copper layer resulted in a potential requirement of 98 mV, to achieve current densities of 10 mA cm−2, compared to 120 mV, when the porous copper substrate was not present. The ECSA was found to be significantly increased by the presence of the copper layer, as determined by examining the CV test and calculating the electrochemically active surface area. Ni3S2@Cu@NF is an excellent choice for electrocatalyst when it comes to HER in alkaline media.

Rapid preparation of high efficiency hydrogen evolution catalyst with hydrophilicity

The electrolytic water method is an outstanding hydrogen production process because of its high stability and no restriction. A low-priced and efficient catalyst for electro-deposition of Ni–Co microspheres and nanoclusters on carbon steel (Ni–Co/CS) has been prepared by the dynamic hydrogen bubble template. In the 6 M KOH solution, Ni–Co/CS only requires an overpotential of 48 mV to provide a current density of 50 mA cm−2. At the same time, it also has a large electrochemically active specific surface area (ECSA) and a hydrophilic surface. In addition, the study about the influence of carbon steel (CS) on Ni–Co coatings and the comparison experiment for different base materials has been completed. The results prove that CS is an excellent base material for hydrogen production. It can help the Ni–Co catalyst to have a stable electrolysis in 6 M KOH for 500 h. The above properties of Ni–Co/CS catalyst make it a new choice of hydrogen production by electrolysis of water in practical applications.

Geometrical recognition of metallic foam microstructures using a deep learning approach

The geometric characteristics of nanostructured porous metallic foams (NMFs) impact their properties, enabling applications in electrocatalysis, energy conversion, and energy storage. The morphology of these three-dimensional (3D) structures is complex, in large part, because of their complicated formation mechanisms. This work presents a computational strategy for geometrically characterizing different NMFs designs. Three types of samples were synthesized using the dynamic hydrogen bubble template electrodeposition method. A set of microscopic confocal images of NMFs was used as training input samples. Herein, a variational autoencoder (VAE) was adjusted under a pretext task, allowing learning embedding descriptors to represent the geometry of microscopic observations. To evaluate the feasibility of using a VAE to assist in the classification of NMFs, a set of machine learning classifiers was implemented to discriminate among the groups of embedded vectors according to their classes. Furthermore, the capacity of the VAE was validated regarding the capability to separate the vectors according to their classes. Explainability mechanisms stand out geometrical features of input images that had major support during the classification task.