Paired organic electrolysis has re-emerged as a compelling strategy for increasing the synthetic value, electron utilisation and energy efficiency of organic electrosynthesis. By deliberately selecting both half-reactions, paired systems can employ electric power to promote the formation of added-value products, and/or to achieve a lower cell voltage, whilst reducing their dependence on purely charge-balancing processes such as the oxygen evolution reaction (OER). Recent advances demonstrate that paired electrolysis is expanding from biomass-derived substrates and CO2-derived products towards recycle-derived substrates, chemically interdependent reactions and reagent electro-generation. Furanics, phenolics, carboxylates, glycerol, polymer-derived ethylene glycol and CO2 have been exploited to access polymer precursors, C1 and C2 oxygenates, organic carbonates, H2O2, acrolein, ammonia and complex organic products. More chemically integrated systems have enabled convergent C-C bond formation, Shono-type oxidation/phthalide synthesis, oxime formation, cyclic amine functionalisation, nitrate-to-ammonia coupling, and in situ generation of H2O2, formaldehyde and hydroxylamine. Several reports now approach process-relevant operation through flow cells, membrane-electrode assemblies and zero-gap electrolysers, with current densities at or above 100 mA cm-2 and extended stability tests. These advances also show that productive chemistry at both electrodes is only the starting point. Successful electrochemical pairing requires compatible electron demand, reaction rate, electrode potential, electrolyte and pH conditions, limited crossover, sufficient product concentration, stable intermediates and feasible downstream processing. Herein, recent advances in paired organic electrolysis are evaluated and the criteria for selecting, operating and reporting paired systems that merit further development beyond proof-of-concept electrolysis are proposed, with an emphasis on reactor choice, cell voltage over time, product recovery, failure modes and preliminary techno-economic assessments.
Electrochemical aptamer-based (E-AB) sensors are a major topic of research, yet their transition from laboratory proof-of-concept to robust real-life applications remains limited. This phenomenon can partly be explained by examining the fundamental physicochemical challenges at the bio-interface. This review provides a critical perspective on two decisive factors: interfacial functionalization and electrochemical interrogation. We argue that because E-AB performance is governed by electron transfer at the electrode-electrolyte boundary, the choice of immobilization chemistry is an important factor for analytical stability and sensitivity. Furthermore, we exemplify how different electrochemical techniques, ranging from square-wave voltammetry to impedimetric methods, impact electrode longevity and signal reliability. We believe the two aspects are the main contributing factors influencing the performance of E-AB sensors.
Electrochemical nucleic acid biosensors offer rapid, low-cost, and miniaturizable platforms for point-of-care molecular diagnostics, but their performance is often limited by low target abundance, insufficient sequence discrimination, and unstable signal transduction in complex samples. CRISPR-Cas systems address these limitations through programmable nucleic acid recognition and collateral-cleavage-mediated reporter conversion. This review summarizes recent progress in CRISPR-Cas electrochemical biosensors from the perspective of multistage amplification. We organize current strategies into three functional levels: target enrichment by isothermal amplification, cascade trigger generation by programmable DNA molecular machines, and interface transduction enhancement by functional nanomaterial engineering. We further discuss AI-assisted signal interpretation for correcting baseline drift, matrix noise, and device variability. Representative applications in infectious disease diagnosis and tumor liquid biopsy are highlighted, together with key translational challenges, including one-pot compatibility, background interference, multiplexing, reproducibility, and clinical validation. Future development should prioritize better-integrated amplification for standardized, clinically deployable, portable nucleic acid diagnostic platforms worldwide.
The surface transport and interactions of specifically adsorbed species at electrochemical interfaces plays a key role in many electrode processes. Over the past decades, advances in in situ techniques for electrochemical environments, in particular high-speed electrochemical scanning probe microscopy, have enabled molecular-level investigations into the quantitative dynamics and elementary mechanisms of these atomic-scale events. This review highlights recent developments in this technique and new observations that provide fresh insights into the formation and diffusion of adsorbates on electrode surfaces, in particular under crowded conditions, as well as the structural fluctuations and reaction dynamics of adsorbate adlayers.
Growing healthcare demands, advancements in flexible electronics, and the development of digital health technologies have made wearable sensors essential tools for continuous, noninvasive health monitoring. These sensors provide up new avenues for early diagnosis and individualized treatment by enabling continuous monitoring of physiological and biochemical information. This critical review provides a comprehensive evaluation of recent advances in wearable electrochemical sensors, with emphasis on sensor construction, functional materials, sensing principles, biofluid selection, artificial intelligence (AI), Internet of Things (IoT) integration, and emerging trends, while critically discussing current limitations and future opportunities. This review first introduces the basic components, advanced materials, fabrication methods and working principles, covering electrochemical, piezoelectric, triboelectric, capacitive, piezoresistive, optical, and magnetic sensing approaches. Next the wearable systems for biofluid analysis, including sweat, interstitial fluid, saliva, and tears, which enable noninvasive biochemical intelligent health monitoring are discussed. The review also highlights the role of AI and machine learning in data interpretation, along with wireless communication and IoT technologies for real-time applications. The latest developments in wearable electrochemical sensors-including advanced techniques, closed-loop systems, multimodal sensor integration, and self-powered sources are further explored. Lastly, prospective directions for next-generation wearable sensing systems in healthcare are discussed, along with present issues with reliability, long-term stability, data management, and widespread adoption.
The rapid development of new psychoactive substances (NPS) has intensified the demand for portable, cost-effective alternatives to conventional chromatographic methods. Electrochemical sensors offer advantages like rapid response, miniaturization potential, and low cost, yet their real-world deployment remains constrained by matrix effects, signal overlap, and the lack of genuine integration of artificial intelligence (AI) within the analytical workflow. This critical review examines recent advances (2024–2026) in machine learning (ML)-powered electrochemical sensors for the detection of drugs of abuse, assessing whether AI is solely used as post-acquisition data-analysis tool or embedded within the analytical workflow.Two detection strategies were identified: electrochemical fingerprinting on various platforms and biomimetic approaches employing aptamers or molecularly imprinted polymers (MIPs). Although ML algorithms can improve classification accuracy, they cannot completely resolve the issues of low selectivity and sensitivity of electrochemical sensors. Dataset quality, algorithm selection, applications in real samples, and model robustness were critically analyzed.Findability, accessible, interoperable, and reusable (FAIR)-compliant datasets, multi-analyte sensing platforms, and explainable AI (XAI) methods represent priorities for enabling reliable, decentralized drug monitoring in real-world scenarios. The most notable gaps are related to the absence of embedded on-device ML implementation, insufficient and non-standardized training datasets, inadequate assessment of real matrix variability, and lack of XAI approaches required for forensic and clinical validation.
The emphasis put on the effects of the interfacial microenvironment in heterogeneous electrocatalysis has not been met in homogeneous molecular electrocatalysis. While it is widely recognized that the microenvironment governs activity, selectivity, and stability in heterogeneous systems, the catalytic behavior of the molecular catalysts has traditionally been interpreted using simplified mechanistic models that largely neglect the role of the electrode/electrolyte interface. Emerging yet limited evidence on both homogeneous and heterogenized molecular catalysts reveals that the reaction energetics and reactant availability through comprehensive electrolyte and electrode engineering can profoundly impact catalytic pathways, suppress competing reactions, and stabilize key intermediates. Consideration of the hydrophobicity, solvent and reactant availability, proton activity, electrolyte composition, and local electric field at the interfacial microenvironment may significantly enhance the electrocatalytic performance of molecular catalysts. This opinion presents a comparative perspective, highlighting how microenvironment-based concepts can provide valuable insight for understanding and designing next-generation molecular electrocatalytic systems.
Scanning electrochemical cell microscopy (SECCM) is a powerful technique for high-resolution electrochemical mapping and localised electroanalysis at the nanoscale, enabled by a mobile droplet cell. Building on recent advances in the study of single entities, crystalline materials, and individual grains of polycrystalline surfaces, this article focuses on the application of SECCM to the direct electrochemical analysis of grain boundaries on metallic electrodes. Emphasis is placed on the inherent complexity of grain boundary behaviour, the advantages of SECCM relative to conventional macroscopic electrochemical approaches, and recent methodological developments that enable increasingly rigorous interrogation of grain boundary electrochemistry.
Electrocatalysis is a central topic in energy conversion technologies, including hydrogen evolution reaction (HER), Oxygen evolution reaction (OER), CO2 or oxygen reduction reactions (CO2RR, ORR), methanol, ethanol, formic acid, or glucose oxidation reactions (MOR, EOR, FAOR, GOR), where gold nanomaterials are widely employed as catalysts. However, the role of surface ligands in tuning both the catalytic and optical properties of gold nanoparticles (AuNPs) remains insufficiently explored. Ligand functionalization plays a pivotal role in governing both catalytic activity and light-induced processes across the UV–vis–NIR region by modulating the electronic structure of the metal surface and the interfacial microenvironment. Altogether, this review highlights ligand engineering as a powerful and versatile strategy for designing efficient and selective catalytic systems, spanning from electrocatalysis to plasmon-assisted electrocatalysis (PAEC) where light and electrochemistry synergistically improve reaction efficiency. Indeed, the plasmonic properties of AuNPs, arising from localized surface plasmon resonance (LSPR), enable light-driven enhancements through hot carrier generation, local heating, and electromagnetic field effects. In this context, the integration of molecular electrocatalysts onto AuNP surfaces emerges as a promising yet underexplored strategy. Strongly grafted molecular systems can facilitate rapid charge transfer and enhance catalytic performance under illumination. Overall, the combination of controlled surface grafting and plasmonic effects offers a powerful platform for designing advanced hybrid catalysts. Although still in its early stages, this approach holds significant potential for developing efficient, selective, and durable systems for sustainable energy and feedstock conversions.
Proton exchange membrane water electrolysis (PEMWE) is a key technology for sustainable hydrogen production; however, the sluggish oxygen evolution reaction (OER) in highly corrosive acidic environments acts as a major hurdle on commercialization. This review systematically examines recent research trends in OER electrocatalysts, covering both noble and non-noble metal-based materials. For noble metal catalysts, we analyze compositional and structural design strategies—including atomic structuring, strong oxide-support interactions, and high-entropy alloying—to minimize content while maximizing mass activity and long-term stability. Additionally, new classes of non-noble metal catalysts exhibiting stability in acidic environments are explored, with a particular emphasis on spinel oxides, high-entropy chalcogenides, and Mn-based materials. Mechanistic discussions on the adsorbate evolution, lattice oxygen, and oxide path mechanisms are incorporated throughout. Finally, we highlight future research directions, including machine learning-accelerated catalyst discovery and the translation of laboratory-scale performance metrics to industrially relevant membrane electrode assembly conditions.
Sequential paired electrolysis, where a substrate is converted to an intermediate at one electrode and into a final product at the opposite electrode, is a powerful tool for (redox-neutral) single-cell cascade reactions. In this opinion, we highlight three key challenges for sequential transformations and discuss practical solutions for overcoming these obstacles based on the recent literature. First, we describe how electron mismatch between half-reactions may limit theoretical current efficiencies and require the utilization of additional counter reactions. Second, we examine how interelectrode mass transport of reactive intermediates can hinder both reaction rates and yields, especially for short-lived radical species. Flow-microreactors or interdigitated electrodes are discussed as alternative cell designs to improve mass transfer, whereas rapid alternating polarity can be used to circumvent this requirement altogether. Third, we address how low intermediate concentration and its depletion at the second electrode may present challenges for process intensification. In addition to the design of electrochemical cells and applied waveforms, the use of redox mediators can provide means for improving space-time yields.
Electrochemical immunosensors have traditionally been explored as highly sensitive analytical tools for detecting protein biomarkers in cancer diagnostics. This minireview presents a timely perspective that redefines their role as enabling platforms for holistic and omics biomarker analysis. Moving beyond the conventional focus on single-analyte detection and signal amplification strategies, the versatility of electrochemical immunosensors for analyzing diverse cancer-associated biomarkers at multiple biological levels is highlighted. Furthermore, their emerging potential is emphasized not only for sensitive quantification but also for biomarker discovery, validation, and interactome analysis, as well as their integration with advanced multi-omics technologies. By situating these platforms within the framework of precision oncology and comprehensive molecular profiling, new opportunities are outlined for bridging the gap between fundamental biomarker research and clinically relevant applications.
The electrochemical ammonia oxidation reaction (AOR) has regained attention due to its potential to enable distributed hydrogen production via ammonia electrolyzer. However, the practical device-level performance still falls well below its thermodynamic promise. This review argues that the primary challenge is no longer simply to find more active catalysts, but rather to understand and control the entangled processes that govern whether a productive working state can be sustained. We advocate a paradigm shift in catalyst design from the sole tuning of intermediate adsorption to a joint optimization of operating efficiency and longevity, with explicit consideration of electrified interfacial parameters. We also examine the device-level AOR performance and highlight that the membrane, catalyst architecture, and operating protocols all strongly affect outcomes. Future progress should therefore focus on defining a deployable working window through the coordinated design of catalysts, interfaces, and operating conditions.
The stability of electrodes during electrochemical operation is an increasingly relevant topic in the maturing of electrochemical technologies. One of the phenomena of interest is the degradation of metals in aqueous solutions at negative potentials (with respect to the onset of the hydrogen evolution reaction), or ‘cathodic corrosion’. Despite being observed on an increasing number of electrode materials and under various reaction conditions, the underlying mechanisms of cathodic corrosion processes are still poorly understood. Such a lack of understanding impedes the rational design of mitigation strategies and hampers our ability to separate different structure-altering phenomena occurring at these potentials. In this mini review, we describe recent phenomenological observations on the progression of the cathodic corrosion process, considering platinum and gold electrodes as the most well-studied electrode materials. We evaluate whether different proposed mechanisms agree with experimental results, and argue that none of the currently proposed mechanisms satisfy all experimental observations.
