Oliver Rodriguez

National Physical Laboratory | NPL · Electrochemistry group

Characterizing the decomposition of electrogenerated species in solution is essential for applications involving electrosynthesis, homogeneous electrocatalysis, and energy storage with redox flow batteries. In this work, we present an automated, multiplexed, and highly robust platform for determining the rate constant of chemical reaction steps fol...

Here, we develop and show the use of an open-source Python library to control commercial potentiostats. It standardizes the commands for different potentiostat models, opening the possibility to perform automated experiments independently of the instrument used. At the time of this writing, we have included potentiostats from CH Instruments (models...

Electrochemical research often requires stringent combinations of experimental parameters that are demanding to manually locate. Recent advances in automated instrumentation and machine-learning algorithms unlock the possibility for accelerated studies of electrochemical fundamentals via high-throughput, online decision-making. Here we report an au...

Theoretical models used to describe the catalyst layers (CLs) in polymer electrolyte membrane fuel cells (PEMFCs) are reviewed, with a focus on continuum treatments as incorporated in device-scale models used to predict and optimise PEMFC operating performance. Consideration is given to the mathematical relationships between CL design properties (P...

The urgency to develop innovative electrochemical energy storage systems has increased exponentially as many governments across the world adopt net-zero strategies that rely heavily on transport electrification. This means that ensuring the repeatability and reproducibility of electrochemical data produced in battery research is one of the most imp...

Electrochemical research often requires stringent combinations of experimental parameters that are demanding to manually locate. Recent advances in automated instrumentation and machine-learning algorithms unlock the possibility for accelerated studies of electrochemical fundamentals via high-throughput, online decision-making. Here we report an au...

Developing a deeper understanding of dynamic chemical, electronic, and morphological changes at interfaces is key to solving practical issues in electrochemical energy storage systems (EESSs). To unravel this complexity, an assortment of tools with distinct capabilities and spatiotemporal resolutions have been used to creatively visualize interfaci...

Here, I introduce Soft Potato, an open source electrochemical simulator and toolkit that contains typical electrochemical equations and simulations to aid researchers streamline their data analysis when dealing with large datasets. As examples, I show here how to use it to calculate steady state voltammograms from ultramicrodisc electrodes and obta...

Currently, hydrogen production is based on the reforming process, leading to the emission of pollutants; therefore, a substitute production method is imminently required. Water electrolysis is an ideal alternative for large-scale hydrogen production, as it does not produce any carbon-based pollutant byproducts. The production of green hydrogen from...

Current hydrogen production is based on the reforming process leading to the emission of pollutants; therefore, a substitute production method is imminently required. Water electrolysis is an ideal alternative for large-scale hydrogen production, as it does not produce any carbon-based pollutant byproducts. Production of green hydrogen from water e...

Current hydrogen production is based on the reforming process leading to the emission of pollutants; therefore, a substitute production method is imminently required. Water electrolysis is an ideal alternative for large-scale hydrogen production, as it does not produce any carbon-based pollutant byproducts. Production of green hydrogen from water e...

In this study, we employed microelectrodes and scanning electrochemical microscopy (SECM) to investigate the role of molecular oxygen and local pH changes on the electrochemistry of Pt oxide. We show that in acidic media and alkaline conditions, the impact of O 2 is negligible, while in unbuffered neutral media, O 2 strongly affects the formation o...

In sampled current voltammetry, a sampled current voltammogram (SCV) is constructed by performing a number of potential steps and plotting the currents taken at a specific sampling time against the corresponding step potentials. For diffusion-controlled processes, the technique produces sigmoidal current-potential curves that are easily analysed to...

Herein, sampled current voltammetry (SCV) is exploited to study the kinetics of electrochemical reactions with electrode materials that are unsuitable for rotating disc or microelectrode experiments. The approach described opens up the possibility of assessing the electrocatalytic activity of films produced by high throughput deposition techniques,...

A greener methodology to grow TiO2 nanotubes in a non-corrosive, low-hazard, fluoride-free ethylene glycol/water electrolytic bath is presented. Results demonstrate that the formation of nanostructures by anodization of Ti foils in NaCl solutions requires glycol/water solutions with water contents (> 50%) and moderate voltages (< 30 V). Nanotube gr...

Perry and Denuault reported the presence of an oxygen species that adsorbed on Pt microelectrodes after the electrode was exposed to dissolved oxygen [1, 2, 3]. This species could only be detected at the millisecond scale and when using a neutral and unbuffered media. Although they suggested that the species was oxygenated in nature, its true ident...

Recently, adsorbed oxygen species (adspecies) have been detected at the millisecond scale on different metallic microelectrodes after being exposed to dissolved oxygen 1,2 . Comparing the experimental current of the oxygen reduction reaction (ORR) with a theoretical diffusion controlled current, it was revealed that both, the adsorbed and diffusion...

This poster will present recent results obtained for the reduction of dioxygen on perovskite microelectrodes. Briefly, a perovskite powder (La0.58Ag0.4Ni0.6Cu0.4O3) was synthesised using the Pechini method 1 and suspended in a solution consisting of conductive carbon, Nafion, water and ethanol. A 50 μm Ø gold disc electrode was recessed by potentio...

The oxygen reduction reaction (ORR) was studied using Pt based microelectrodes under different mass transfer regimes. Current transients at different potentials were recorded by first applying a cleaning waveform and a rest potential 1–3 transformed to sampled current voltammograms and finally normalised using the equation proposed by Mahon and Old...

This poster will present recent results obtained for the reduction of dioxygen on perovskite microelectrodes. Briefly, a perovskite powder (La 0.58 Ag 0.4 Ni 0.6 Cu 0.4 O 3 ) was synthesised using the Pechini method ¹ and suspended in a solution consisting of conductive carbon, Nafion, water and ethanol. A 50 μm Ø gold disc electrode was recessed b...

The presence of sulfates potentialize damage on cement-based materials, leading to structural failures. Therefore, structures must be designed to compensate for this effect. The mechanical properties of cement–chitin mixtures are investigated with different percentages of chitin (0.5, 1.3, and 2.1 wt.%) and aging of composite in a joint nanoscopic-...

In this work presents a study of the morphology and Young’s modulus of the E.coli bacteria treated with silver nanoparticles in different sizes (14 and 60nm) and different exposure times (0,15,30 min). Force-distance curves were taken in contact mode and adjusted to model Hertz with Igor Pro software. In the images shown that the size of the untrea...