Control of magnetism through electric-field-driven migration of ions, referred to as magneto-ionics (MI), holds promise for the development of non-volatile energy-efficient memory storage, as well as spintronic, neuromorphic and magnetoelectric devices. Here, we study the MI phenomena in 350 nm thick Ni55Co45 oxide films with varying degrees of porosity, obtained by electrodeposition of the parent Ni-Co metallic alloy on metallized Si substrate and subsequent annealing in air. Annealing at 450 °C of the film electrodeposited from a P-123-containing electrolyte with Ni and Co sulfate salts yields a Ni-Co oxide that partially retains its mesoporosity. This sample exhibits a higher MI response compared to a low-porosity (nearly dense) Ni-Co oxide film, indicating that an increased surface-to-volume ratio enhances MI. Comprehensive characterization of the mesoporous Ni-Co oxide-coated Si/Ti/Au sample reveals that annealing not only oxidizes the top ≈100 nm of the Ni-Co film but also induces silicon diffusion. MI phenomena occur via O2- migration out of and into the top Ni-Co oxide layer under negative and positive biasing, respectively. While the system shows some irreversibility, endurance improves significantly as cycling frequency increases, evidencing the potential of this material for voltage-tunable memory applications.

Porous Ni–W alloy films were fabricated by electrodeposition from a gluconate‐based electrolyte using three approaches: (i) micelle‐assisted deposition with Pluronic P‐123, (ii) colloidal crystal templating, and (iii) a combination of both. Hierarchically porous films were produced either by plating from a P‐123‐containing electrolyte onto substrates patterned with 200 nm polystyrene spheres, or from a P‐123‐free electrolyte onto substrates patterned with mixed 20 and 200 nm spheres. Dense Ni–W films were deposited under comparable conditions for reference. The tungsten content ranged from 1 to 19 wt.% depending on the method. All coatings were nanocrystalline single‐phase face‐centered cubic alloys, with diffraction peaks shifting to lower 2θ values as W content increased. Electrochemical evaluation of the hydrogen evolution reaction in 0.5 M H2SO4 revealed superior catalytic performance for the multiporous films templated with 20 and 200 nm spheres, achieving an overpotential (η10) of 300 mV versus reversible hydrogen electrode at −10 mA cm–2 and a Tafel slope of ∼134 mV dec–1. The enhanced activity was attributed to the combined effect of high surface area and increased W content, while long‐term durability improved primarily with higher W content, as confirmed by 24 h potentiometry at −10 mA cm–2.

Merging electrochemistry with magnetism offers a compelling pathway for next-generation memory and computing technologies by enabling voltage-driven control of magnetic properties through ionic motion and interfacial redox reactions. This approach allows continuous, analog, and history-dependent tuning of magnetism, in contrast to conventional electronic methods based on binary switching, therefore opening opportunities for adaptive functionalities. By dynamically reshaping the material landscape (i.e., modifying magnetic order, anisotropy or exchange interactions) electrochemical modulation supports neuromorphic and in-memory computing architectures where processing and storage are intrinsically coupled. This Editorial highlights recent progress in electrochemically controlled magnetism while addressing key challenges, including time-scale mismatches between ionic and electronic processes, long-term reliability, variability, integration with existing technologies, and the need for standardized performance metrics. More broadly, this emerging computing paradigm points toward a shift from static circuits to dynamic materials that evolve, adapt and compute, embedding intelligence directly within their chemical state and structure.

Electric-field control of ferromagnetism is demonstrated in a mechanically flexible solid-state system through a proton-induced redox reaction at room temperature. Protons transported through a perfluorosulfonic acid (PFSA) proton exchange membrane (PEM) trigger the reduction of CoO by reacting with lattice oxygen, which enables reversible switching between paramagnetic and ferromagnetic states starting at voltages below 10 V. The proton supply is sustained by ambient humidity and water splitting at a Pt thin film counter electrode. Due to its flexibility, the device architecture-a sandwich of CoO and Pt thin films integrated with the polymeric PEM-retains full magneto-ionic functionality under mechanical bending. Three CoO films, synthesised via reactive sputtering under varying conditions, are compared: amorphous, crystalline, and mixed-phase CoO/Co. While the amorphous film exhibits weak response, both the crystalline and mixed-phase films show pronounced electric-field-dependent magnetic switching, highlighting the critical role of microstructure in magneto-ionic performance. (c) 2026 The Authors. Published by Elsevier B.V. on behalf of The Chinese Ceramic Society. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Voltage control of magnetism via magneto-ionics, where ion transport and/or redox processes drive magnetic modulation, holds great promise for next-generation memories and computing. This stems from its non-volatility and ability to precisely tune both the magnitude and speed of magnetic properties in a potential energy-efficient manner. However, expanding magneto-ionics to incorporate novel mobile ions or even multiple ion species is crucial for unlocking new phenomena and enabling multifunctional capabilities. Here, we demonstrate voltage-driven multi-ion transport in an FeBO system with increasing oxygen content, progressively transitioning from an electrostatic-like response to a more pronounced electrochemical (magneto-ionic) behavior. The voltage-driven transport of both B and Fe is activated by oxidation state tuning, owing to the larger electronegativity of oxygen. Such charge-transfer effects allow multi-ion magneto-ionics, where O ions move oppositely to Fe and B ions. These results pave the way for programmable functionalities by leveraging elements with different electron affinities through charge-transfer engineering.

In order to maximise electrochemically active surface area for water splitting, mesoporous Ni-Pt nanoparticles (NPs) are electrodeposited onto open-cell Ni foam to obtain a dual (macro- and meso-) porosity. Homogeneous deposition of the NPs is achieved by the use of a cylindrical Pt-coated mesh counter electrode, establishing a uniform electric field around the Ni foam substrate during electrodeposition. The Ni/Pt ratio is tunable with the electrodeposition parameters and all NPs are single-phase face-centred cubic solid solution and nanocrystalline, with a pore size of approx. 10 nm. Ni foam decorated with the Ni-rich particles, with mean particle sizes ranging from 50 to 80 nm, shows significantly higher activity at hydrogen evolution reaction (HER) in alkaline media with respect to the bare Ni foam. The highest HER efficiency was found fora relatively low Pt content of the NPs of about 26 at% (i. e., at 74 at% Ni) with an improvement of a factor 8 over bare Ni foam after durability assessment. These improvements are attributed to the higher surface area thanks to the NP structure, the dual porosity, and the alloying with Pt.

Magneto-ionic materials, which enable nonvolatile control of magnetism through voltage-driven ion migration, are emerging as promising candidates for neuromorphic computing. Unlike conventional memristors, these systems allow dual actuation by both electric and magnetic fields, providing a broader range of functional capabilities. The reliance on voltage rather than current significantly reduces Joule heating and enhances the energy efficiency. However, the general need for external magnetic fields to modulate the voltage-induced magnetic response remains a key limitation, undermining the full energy-saving potential of these systems. In this work, we present a magneto-ionic strategy in CoFeN that fully decouples the electric and magnetic field requirements. By taking advantage of a planar N3- ion migration and the ferromagnetic exchange interactions between preexisting and newly generated CoFe magnetic regions, we achieve remanent-state magnetization control solely through applied voltage. The system exhibits behaviors reminiscent of neuromorphic-inspired functionalities, such as synaptic potentiation and depression, while also exhibiting a cumulative voltage-driven increase in magnetization in the absence of a magnetic field. Once the magnetic field is switched off, synaptic weight remains influenced by both the sample's magnetic and electric history. By eliminating the need for magnetic fields, our approach contributes to reduce energy consumption, offering a more efficient pathway for brain-inspired magneto-ionic devices.

The oxygen reduction reaction (ORR) is one of the central points of research in proton exchange membrane fuel cells (PEMFC). A reduction of the Pt content of fuel cell electrodes is envisaged to lower their production cost, and the complete abandonment of Pt at the cathode by the use of Pt-free electrocatalysts is one of the many approaches to do so. The most developed Pt-free catalysts, M–N–C (where M is usually a transition metal) with atomically dispersed MN4 sites, are close to industrial requirements in terms of catalytic activity. Their major critical issue, a sufficient stability under operating conditions, can be effectively tackled by controlling the atomic configuration of the active sites.

The hydrogen evolution reaction at Ni foam electrodes is enhanced by magnetic fields of up to 12 kOe applied perpendicular to the electric field. While in 1 M KOH, the beneficial change in overpotential at an applied field is on the order of 10 mV, the effect increases drastically when the concentration of OH-is reduced to 0.1 M and 0.01 M, respectively, leading to a change in overpotential of up to 200 mV at the lowest concentration of OH-, making the reaction significantly more energy-efficient. The addition of KCl as a supporting electrolyte effectively suppresses adverse effects originating from the low conductivity of 0.01 M KOH while preserving the advantageous effects of the magnetic field. Finally, the effects are studied in neutral 1 M KCl, likewise leading to an improvement in HER of up to 200 mV in overpotential, and in filtered seawater, where the overpotential improves by 28 mV when applying 12 kOe. The effects of magnetic fields on HER are shown to be reversible, and scale with the magnitude of the field. In addition to chronopotentiometry at-10 mA where magnetic field pulses generate a pulse in the HER overpotential, measurements are complemented by linear sweep voltammetry and electrochemical impedance spectroscopy.

Voltage-driven ion motion offers a powerful means to modulate magnetism and spin phenomena in solids, a process known as magneto-ionics, which holds great promise for developing energy-efficient next-generation micro- and nano-electronic devices. Synthetic antiferromagnets (SAFs), consisting of two ferromagnetic layers coupled antiferromagnetically via a thin non-magnetic spacer, offer advantages such as enhanced thermal stability, robustness against external magnetic fields, and reduced magnetostatic interactions in magnetic tunnel junctions. Despite its technological potential, magneto-ionic control of antiferromagnetic coupling in multilayers (MLs) has only recently been explored and remains poorly understood, particularly in systems free of platinum-group metals. In this work, room-temperature voltage control of Ruderman-Kittel-Kasuya-Yosida (RKKY) interactions in Co/Ni-based SAFs is achieved. Transitions between ferrimagnetic (uncompensated) and antiferromagnetic (fully compensated) states is observed, as well as significant modulation of the RKKY bias field offset, emergence of additional switching events, and formation of skyrmion-like or pinned domain bubbles under relatively low gating voltages. These phenomena are attributed to voltage-driven oxygen migration in the MLs, as confirmed through microscopic and spectroscopic analyses. This study underscores the potential of voltage-triggered ion migration as a versatile tool for post-synthesis tuning of magnetic multilayers, with potential applications in magnetic-field sensing, energy-efficient memories and spintronics.

Dense and porous Ni and Ni-W alloy films were fabricated via electrodeposition, with the porous structures produced using colloidal crystal templates composed of 20 and 200 nm polystyrene spheres. The study investigates the effects of tungsten content (6-9 wt%) and porosity on the films' mechanical and magnetic properties, as well as their structural stability at elevated temperatures. From a crystallographic viewpoint, both Ni and Ni-W films exhibited a face-centered cubic (fcc) structure, with the diffraction peaks of the Ni-W films shifted toward lower angles due to the alloying of W with Ni. Interestingly, peak splitting was observed in the porous films, which originated from the confined metal growth between the polystyrene spheres. All films were nanocrystalline, with crystallite sizes in the range of 17 - 46 nm. Tungsten addition to nickel enhanced mechanical hardness but decreased magnetic moment and Curie temperature. Porosity, on the other hand, introduced new magnetic contributions not observed in dense films, including superparamagnetic behavior in the Ni-W films with 200 nm-size porosity. Thermal analysis revealed that the porous Ni-W films were morphologically stable up to 800 K, whereas porosity in pure Ni films degraded at 600 K. These findings highlight the potential of Ni-W coatings with tailored porosity for magnetic microelectromechanical systems and sustainable multi-functional coatings.

Understanding the kinetic behavior and mechanism of electrodeposition is crucial for controlling alloy deposition processes, yet many aspects remain unresolved despite decades of research. This study combines experimental, theoretical and computational strategy. The latter utilizes a Multi-Ion Transport and Reaction model (MITReM) coupled with finite element simulations (FEM) to predict the co-deposition behavior of nickel-tungsten (Ni-W) alloys in an electrolyte containing nickel sulfate, sodium tungstate, and sodium gluconate as a complexing agent. The model incorporates key transport and reaction phenomena, including diffusion, migration, convection, and the simultaneous deposition of multiple ionic species, focusing on the kinetics of nickel deposition, tungsten codeposition, and the hydrogen evolution side reaction. Cyclic Voltammetry (CV) and Linear Sweep Voltammetry (LSV) with Rotating Disk Electrode (RDE) techniques were used to determine kinetic parameters and diffusion coefficients for Ni and W by comparing experimental polarization data with simulation results. The strong agreement between simulated and experimental data validates the model, showing that increased agitation enhances Ni deposition while having no significant effect on W due to its complex multi-electron transfer mechanism and dependence on intermediate adsorption. Numerical simulation by MITRe modeling provides valuable insights for precisely controlling Ni-W electrodeposit composition and advancing the understanding of co-electrodeposition processes.

Control of magnetism through voltage-driven ionic processes (i.e., magneto-ionics) holds potential for next-generation memories and computing. This stems from its non-volatility, flexibility in adjusting the magnitude and speed of magnetic modulation, and energy efficiency. Since magneto-ionics depends on factors like ionic radius and electronegativity, identifying alternative mobile ions is crucial to embrace new phenomena and applications. Here, the feasibility of C as a prospective magneto-ionic ion is investigated in a Fe-C system by electrolyte gating. In contrast to most magneto-ionic systems, Fe-C presents a dual-ion mechanism: Fe and C act as cation and anion, respectively, moving uniformly in opposite directions under an applied electric field. This leads to a 7-fold increase in saturation magnetization with magneto-ionic rates larger than 1 emu cm-3 s-1, and a 25-fold increase in coercivity. Since carbides exhibit minimal cytotoxicity, this introduces a biocompatible dimension to magneto-ionics, paving the way for the convergence of spintronics and biotechnology.

Titanium and its alloys are widely used for implants, although they have limitations like higher elastic modulus compared to bone, causing stress shielding and potential implant failure. To address these issues, beta-Ti alloys and calcium phosphate coatings are being developed to improve the mechanical properties while enhancing bone integration. The risk of infection is another important limitation that can be addressed through the deposition of antibacterial and antibiofilm coatings on the alloys. Here, we present a beta-Ti alloy (Ti-18Mo-6Nb-5Ta (wt %)) coated with calcium-deficient hydroxyapatite (CDHA) and decorated with silver nanoparticles intended to be used as antimicrobial orthopedic implants. The experiments revealed that human osteoblasts were able to adhere and proliferate on coating. The presence of silver nanoparticles did not adversely affect human osteoblast differentiation and led to a 50 % increase in type I collagen production. The coating decorated with silver nanoparticles exhibited a significant antibacterial effect against Staphylococcus aureus, reducing biofilm formation by over 40 % after 24 h compared to the undecorated coating. Taken together, these results show the effectiveness of the silver decorated CDHA coating in enhancing osteoblasts proliferation and differentiation while also reducing biofilm growth when compared to CDHA coating.

Magneto-ionics, which refers to the modification of the magnetic properties of materials through electric-field-induced ion migration, is emerging as one of the most promising methods to develop nonvolatile energy-efficient memory and spintronic and magnetoelectric devices. Herein, the controlled generation of ferromagnetism from paramagnetic Co-Ni oxide patterned microdisks (prepared upon thermal oxidation of metallic microdisks with dissimilar Co-Ni ratios, i.e., Ni25Co75 and Ni50Co50) is demonstrated under the action of voltage. The effect is related to the partial reduction of the oxide phases to their metallic forms. Samples richer in Co show stronger magneto-ionic activity, which manifests in lower-onset threshold voltages, faster switching rates, and larger values of the attained saturation magnetization. By means of scanning electron microscopy, a cobalt segregation phenomenon has been experimentally observed upon thermal oxidation, which has been theoretically discussed from the diffusivities' viewpoint. X-ray diffraction characterization has revealed transitions between purely mixed Ni and Co oxides, in the OFF state, to a mixture of oxide and metallic phases, in the ON state, because of the oxygen ion motion outward/inward the Co-Ni oxide microdisks, depending on the voltage polarity. Ab initio calculations reveal that the energy barrier for oxygen vacancy migration is lower in CoO than in NiO, in agreement with the obtained magneto-ionic responses. The observation of magneto-ionic effects in patterned disks (and not only in archetypical continuous films) is a step further for the practical utilization of this phenomenon in real miniaturized devices.

Thermal decomposition of iron oleate is a simple and widespread method for synthesizing monodispersed iron oxide nanoparticles (IONPs) with well-defined morphology. However, the complexity of the underlying mechanism makes this method rather sensitive to variations in experimental conditions, and the lack of simple techniques to monitor the reaction progress in situ usually results in poor reproducibility and time-consuming optimizations. Here, a simple, robust, and versatile in situ marker to monitor particle formation based on a sudden change in the temperature during reflux is reported. A linear relationship between the onset of particle formation and the concentration of surfactants is unveiled, corroborating a 'chemically activated' burst nucleation mechanism. Using this linear relationship as a guide, highly uniform spherical, cubic, and star-shaped particles between 12 and 30 nm can be obtained. This temperature marker and the derived linear relationship not only deepen the understanding of the reaction process, but also provide a powerful tool for the straightforward optimization of IONPs. The use of a simple, in situ temperature marker of particle formation is demonstrated for the thermal decomposition of iron oleate. The marker reveals a relationship between the onset of particle formation, the concentration of surfactants, and the shape of the particles that corroborates a chemically activated burst nucleation. The marker is tested with multiple solvents, providing particle size and shape control. image