Abstract Quantitatively resolving how electrochemical charge is distributed between dissolution and surface film formation remains a major challenge in interfacial electrochemistry because dissolved and surface-bound species are rarely quantified simultaneously under operando conditions. Here, we introduce a coupled atomic emission spectroelectrochemistry-quartz crystal microbalance (AESEC-QCM) platform that enables time-resolved and quantitatively constrained analysis of electrochemical reactions by simultaneously measuring electron transfer, elemental dissolution, and interfacial mass evolution. Using Cu as a well-established model electrochemical system, we demonstrate quantitative agreement between faradaic charge, dissolved Cu flux, and QCM-derived mass variations during electrodeposition and pulsed anodic dissolution. Residence time distribution analysis further separates intrinsic interfacial kinetics from hydrodynamic dispersion within the flow cell, enabling accurate interpretation of transient dissolution responses. The operando methodology provides quantitative insights into the partitioning of anodic charge during Cu oxidation in synthetic tap water, where dissolution and surface film formation occur concurrently. Combined AESEC-QCM analysis reveals that Cu oxidation proceeds through concurrent dissolution as Cu2+ and formation of a Cu2O surface layer. The oxide composition and quantity are independently validated through subsequent chemical dissolution in citrate buffer, establishing complete closure of the mass-charge balance across electrochemical and chemical transformation steps. The results demonstrate that the coupled AESEC-QCM approach enables direct and quantitative separation of dissolved and surface-bound reaction pathways with nanomole-level sensitivity. More broadly, the methodology provides a general operando platform for investigating complex electrochemical systems involving concurrent dissolution and surface transformation, including multicomponent alloys, conversion coatings, and electrocatalytic materials.

Following technological evolutions, commercial electrochemical devices are now very compact, but often hard to repair, so that we observe an increase of open-source electrochemical hardware. In this paper, we exploit the former hard drive technology to recycle the brushless motor in order to build a polishing machine and a rotating disk electrode (RDE). Each step of the construction is detailed. The RDE performance is evaluated by linear sweep voltammetry of the classical ferrocenedimethanol redox system. Quantification thanks to the Levich equation provides a diffusion coefficient of ferrocenedimethanol of (4.6 ± 1) × 10−10 m2 s−1 in aqueous potassium chloride electrolyte, which is close to the literature, thus validating home-made RDE. Using these devices with the PassStat, an open-source potentiostat allows to build an electrochemical set-up at a very reduced price (less than 150 € for the three devices). The approach will be of specific interest for teaching instrumentation and for countries of lower resources.

This article explores the development of a scalable, contemporary interface designed to replace outdated laboratory control systems. Utilizing Python open source codes like PyVISA, PyQt, and the Prologix GPIB-USB controller, this solution automates the measurement of essential parameters, including frequency and voltage. It meets the requirements of contemporary electrochemical studies with its real-time data acquisition, enhance precision and user-friendly interface. The new developed interface is a flexible to promote scientific investigation since it guarantees dependently, flexibility and enhanced performance.

This work presents 4 open source potentiostat solutions for performing accurate measurements in cyclic voltammetry and square wave voltammetry at a low price. A very simple and easy to reproduce analogic board (c.a. 10 €) was driven either by a Teensy card from the company PJRC under an Arduino/Python software solution (39 €) or by an Analog Discovery 2 device from Digilent (less than 300 €). A smartphone Bluetooth Android interface was also created to circumvent the use of a computer. We demonstrated that our scheme is suitable for measurements in classical electrochemical conditions but also to carry out experiments with ultramicroelectrodes. We could thus reach a noise resolution of less than 1 pA. Scan rates of 8000 Vs−1 with ohmic drop compensation were also achieved. The device is suitable for teaching purposes but also for experiments in a participative science context on the ground, or countries with lower financial possibilities.

The possibility to couple a transient electrochemical detection of the redox intermediates produced by a picosecond electron accelerator is explored. The principle is demonstrated with the well-behaved methylviologen radical cation that can be reoxidised at the electrode and simultaneously detected by transient absorption.