ABSTRACT The hydrogen evolution reaction (HER) in alkaline media is a promising strategy for sustainable hydrogen production, but the exploration of efficient and durable HER electrocatalysts is often hindered by the empirical and time‐consuming nature of traditional synthesis. Herein, a machine learning (ML)–driven strategy combining Bayesian optimization is introduced to achieve the rational design of Ni 3 S 4 /Ni 3 Mo heterostructures for alkaline HER. By coupling predictive modeling with experimental feedback, this approach efficiently navigated a complex synthesis space and identified conditions yielding a structurally and electronically optimized catalyst. The optimized Ni 3 S 4 /Ni 3 Mo exhibits a vibrant morphological evolution—from compact buds to blooming petal‐like structures—enabling enriched active sites and accelerated mass transport. Guided by Bayesian optimization, the optimized Ni 3 S 4 /Ni 3 Mo achieves a 10.5‐fold enhancement in C dl and delivers an exceptionally low overpotential of 18.2 mV at 100 mA cm −2 , outperforming most reported transition‐metal catalysts and even surpassing commercial Pt/C. Mechanistic insights from in situ Raman and DFT reveal that interfacial charge redistribution between Ni 3 S 4 and Ni 3 Mo optimizes H* adsorption (Δ G H* ≈ 0.04 eV) and significantly reduces the water‐dissociation barrier (0.08 eV), thereby accelerating reaction kinetics. This work demonstrates how the ML‐guided optimization can synergistically couple morphology control, interfacial engineering with electronic tuning, offering a generalizable framework for intelligent catalyst discovery and mechanistic understanding in electrochemical energy conversion.

Synthesis of multicomponent oxygen evolution reaction coatings via block copolymer templating with vapor- and solution-phase precursors.

Prussian blue analogues and their derivatives for electrochemical energy conversion

This review summarizes the catalytic mechanisms, confined synthesis strategies, and structure–activity relationships of HDSACs in key electrochemical energy conversion reactions, aiming to guide the rational design of high-performance HDSACs.

Maximizing electrochemical energy conversion and storage performance of carbon aerogel with Co-Fe by tuning the synthesis method

The development of highly efficient and low-cost electrocatalysts is urgently needed for electrochemical energy conversion processes, which typically depend on structural regulation strategies. Herein, we report a microwave-assisted approach to...

Efficient electrochemical energy conversion technique facilitated by Ni3Se2 nanoparticles embedded on PANI interfaces

Advances in structural configurations of microfluidic fuel cells for electrochemical energy conversion

The development of highly efficient and stable oxygen evolution reaction (OER) electrocatalysts represents a critical challenge for advancing water splitting hydrogen production technology. In this work, we report a novel defect engineering strategy through synergistic Fe/Al doping and Co vacancy construction in a CoMOF precursor, achieving remarkable performance enhancement after electrochemical reconstruction. Density functional theory (DFT) calculations elucidate the cooperative mechanism of Fe/Al dopants and Co vacancies, which positions the Gibbs free energy of O (ΔGO*) exactly at the center of ΔGOH* and ΔGOOH*, thereby dramatically decreasing the catalytic overpotential and boosting the catalytic activity. Experimental characterization studies conclusively demonstrate the successful electronic structure modulation achieved through this triple-defect (Fe/Al doping and Co vacancy) synergistic strategy, which exhibits exceptional electrocatalytic performance with an ultralow overpotential of 229 mV at 10 mA cm-2. The concerted effects of these engineered defects not only remarkably enhance the intrinsic activity through optimized electronic configurations but also significantly improve charge transfer kinetics. This innovative defect-engineering paradigm establishes a universal methodology for the rational design of high-performance electrocatalysts across diverse electrochemical energy conversion systems.

Efficient electrochemical energy conversion and storage performance of combined rare-earth metal oxide-MoS2 nanocomposite

Stabilizing crystal structure is a powerful route to unlock new functionalities in perovskite oxides. BaCoO3 (BCO) derivatives are a versatile platform for designing mixed ionic-electronic conductors for solid oxide fuel cell (SOFC) cathodes, yet their stable hexagonal structure limits performance unless transformed into the cubic perovskite phase. Here, seven compositions are systematically investigated -undoped BCO and Sc-, Y-, Zr-, Hf-, Nb-, and Ta-doped variants-and show that the hexagonal-to-cubic transition is the decisive factor governing oxygen reduction kinetics. Among the dopants, Ta proves most effective, achieving a polarization resistance as low as ≈0.004 Ω cm2 at 650°C, by promoting cubic symmetry, which balances oxygen ion transport, oxygen vacancy formation, and surface oxygen adsorption. These findings highlight chemical doping as an effective means to stabilize cubic BCO and offer general design principles for tailoring crystal symmetry and functionality in perovskite oxides for electrochemical energy conversion.

ABSTRACT Anion exchange membrane fuel cells (AEMFCs) offer a sustainable energy solution with non‐precious metal catalysts, reduced degradation, and fuel flexibility. However, the sluggish oxygen reduction reaction (ORR) at the cathode and durability concerns impede commercialization. To address these challenges, this study presents a dual‐atomic SiFe–N–C catalyst derived from pinecones, a naturally abundant biomass resource. The catalyst features a nitrogen‐rich porous carbon matrix that stabilizes Si–Fe dual‐atomic sites during pyrolysis. Advanced analyses confirm Fe–Si and Fe–N bonds, which synergistically enhance ORR activity by optimizing electronic structures and intermediate adsorption energies. The SiFe–N–C catalyst surpasses Pt/C and Fe–N–C single‐atom benchmarks with superior ORR activity and excellent long‐term durability supported by high resistance to CO poisoning as well as methanol crossover. It also demonstrates a promising electrochemical performance as a catalytic material for the separator of Li–S battery. Mechanistic studies reveal that the Si–Fe dual‐atomic configuration promotes an efficient Fe–O–O–Si pathway, reducing energy barriers and offering a cost‐effective, high‐performance solution for electrochemical energy conversion and storage applications.

Increasingly, electrochemical energy storage and conversion technologies are considered key enablers of a deep decarbonization of society. However, given the real possibility that these technologies may delay rather than advance climate action, it is crucial that policymakers, industry, and researchers actively engage in developing principles for more responsible or ‘convivial’ use of these technologies. We demonstrate how current electrochemical research and innovation in green hydrogen and CO2 utilization is embedded in orthodox political-economic discourses and infrastructures. As part of a technology assessment based on Zoellick and Bisht’s (2018) degrowth perspective, we explore examples of electrochemical innovation that could fit heterodox political-economic scenarios and present approaches for future interdisciplinary research on convivial electrochemical innovation.

Salinity gradient energy is a promising marine renewable source that requires high-performance electrode materials for efficient harvesting. While polyaniline (PANI)-intercalated V2O5 enhances ion transport through an expanded interlayer spacing, its practical application is hampered by inherently low electrical conductivity and structural instability. In order to solve the structural stability problem, we co-intercalate Ce3+ and PANI into V2O5 layers Ce@PANI@V2O5 (CPVO), to stabilize the interlayer structure for improving the electrochemical conversion of salinity gradient energy. The results show that the Ce-N and Ce-O bonds formed by the co-intercalation of Ce3+ and PANI stabilized the interlayer structure, and brought a larger pore area, which improves the electrochemical performance of the electrode material. The CPVO has a specific capacitance of 238.0 F g-1 at a current density of 0.2 A g-1. After 1000 cycles, the capacity retention rate is 90.36%. The AC//(0.083M Na2SO4, 0.5M Na2SO4)//CPVO salinity gradient energy conversion device successfully converted an energy density of 9.10 J g-1, paving the way for high-efficiency salinity gradient energy conversion systems.

The efficient activation of molecular oxygen (O2) underpins electrochemical energy conversion; however, the design strategies for non-precious catalysts for the oxygen reduction reaction remain incomplete. Transition metal porphyrins supported on conductive substrates offer a versatile platform, but the mechanism by which different metal centers cooperate to control O2 activation is not well understood. In this work, we used density functional theory to explore heterometallic (Fe, Mn) porphyrin-graphene hybrids and reveal the decisive role of axial-core metal synergy. Across FeTPyP-Fe/Gr, FeTPyP-Mn/Gr, and MnTPyP-Fe/Gr, axial (bridging) sites consistently promote stronger O2 binding, greater charge transfer, and more pronounced weakening of the O-O bond than their core counterparts. Electronic-structure analysis showed that this effect arises from enhanced orbital overlap and π* occupation at the axial position, while Mn incorporation tunes the ligand field to further optimize O2 activation. The most effective configuration combines axial Fe binding with Mn-mediated electronic modulation, demonstrating that the complementary roles of distinct metals can be harnessed in a single catalytic architecture. These findings provide mechanistic insights into oxygen reduction and establish clear design principles for the engineering of earth-abundant porphyrin catalysts. More broadly, they highlight heterometallic coordination as a powerful strategy for tailoring molecular electrocatalysts for sustainable energy conversion.

Exploring highly foldable batteries with no safety hazard is a vital task for the realization of portable, wearable, and implantable electric devices. Owing to these concerns, developing solid-state batteries is one of the most promising routes to achieve this aspiration. Because of the excellent flexibility and process ability, Sodium alginate blends polyvinyl alcohol-based electrolytes possess great potential to pack high energy density flexible batteries, however, suffers the various intrinsic shortcomings such as inferior ionic conductivity, a high degree of crystallinity, and lack of reactive groups. In this present work, polymer electrolyte films based on NaAlg blend PVA doped with NH4VO3 salt were prepared by solution casting method. X-ray diffraction (XRD) explains that the enhancement of conductivity is affected by the degree of crystallinity. Fourier transform infrared (FTIR) spectroscopy analysis confirms the interaction between polymers and salt. For NaAlg/PVA system, a sample containing 15 wt% of NH4VO3 possesses the highest ionic conductivity of 0.67 × 10− 5 S cm− 1. Several electrical and electrochemical characteristics of the prepared electrolytes were examined, including impedance, dielectric behavior, transference number, electrochemical stability window, energy density, specific capacitance (Cs), and power density. The ionic conductivity of the synthesized solid biopolymer electrolyte (SBE) system was found to be influenced by ion mobility (µ) and the diffusion coefficient (D). Hence, the aforementioned results indicate that the developed SBE system holds strong potential for application in electrochemical energy storage and conversion devices such as proton batteries, supercapacitors, and fuel cells.

A flexible energy cascade utilization electrochemical system consisting of an alkaline fuel cell and an electrochemical energy converter

Research advances of amorphous metal oxides with the feature of Pseudocapacitance behavior in Lithium ion battery.

First-principles calculation studies of metal-organic frameworks and their derivatives for electrochemical energy conversion and storage

The rational design of electrodes is crucial for improving electrochemical energy storage and conversion devices. High‐performance devices require porous carbon electrodes with controlled intraparticle properties — such as morphology, size, porosity, elemental composition, and graphitic microstructure — and interparticle features like electrode‐level porosity, percolation pathways, and tortuosity, that influence mass transport. Here, mesoporous N‐doped carbon (MPNC) nanospheres with independently tunable particle size at a fixed pore size is reported. Extending the previously established synthesis toolbox, independent control over particle and pore sizes is demonstrated. Using a 9 nm SiO2 hard template, particle sizes between 50 and 300 nm is adjusted while maintaining comparable physicochemical properties. These MPNC nanospheres are evaluated as supercapacitor electrodes in coin cells using 1.0 m LiPF6 in EC/DEC as electrolyte. The highest specific capacitance — 67 F g−1 at 0.1 A g−1 — is obtained with the largest particles, attributed to reduced tortuosity and improved electrode percolation. As all samples exhibited similar surface areas (≈950 m2 g−1), performance differences highlight particle size‐dependent diffusion limitations. This study establishes a bottom‐up approach for engineering electrode architectures, enabling independent control of pore and particle sizes of MPNC nanospheres and providing a platform to systematically investigate their effects on electrochemical performance.