Electrochemical Imaging of Dynamic Electrochemical Interfaces
Electrochemistry is playing an essential role in modern energy-related technologies such as batteries, fuel cells and electrolytic processes. Understanding electrochemical processes that control the performance and stability of battery interfaces such as ion (de)intercalation, formation of solid-electrolyte interfase, dendrite growth, etc. will be essential for the development of enhanced, safer batteries with longer lifespan.
I currently work at Prof. Patrick Unwin’s group in the University of Warwick (UK). We aim to implement in situ electrochemical imaging in controlled atmospheres to investigate the dynamic processes happening at the nanoscale in battery electrode interfaces. This is a multidisciplinary project funded by the Faraday Institution with the overall goal of understanding multi-scale dynamics in batteries by combining and correlating a powerful range of imaging techniques together with other leading groups in the UK.
More information coming soon…
Electrocatalysis for the sustainable generation of fuels
I previously worked in the KTH Royal Institute of Technology (Sweden) on cost-effective production of hydrogen by electrocatalytic oxidation of biomass-based organic compounds (alcohols, hydroxyacids, raw materials).
Advances on the electrochemical detection of nanoparticles for biosensing
Electrochemical biosensors may play an important role in the future of medical diagnostics as far as they have interesting advantages to more established methods such as ELISA. On one hand, small, portable, disposable devices can be easily employed as the biosensor platform. On the other hand, results can be quickly obtained with low-cost, portable and user-friendly readers such as a glucometer, converting Electrochemistry in one of the top techniques to perform decentralized analysis with Point-of-Care (POC) devices. An interesting research area involves the utilization of nanoparticles with electroactive properties as detection label in electrochemical biosensing. I have worked under the supervision of Prof. Agustín Costa (University of Oviedo) on the development of novel, simple and sensitive methods for the electrochemical detection of nanoparticles employed in biosensing applications. Our most relevant advances achieved on this field are summarized below:
- In situ detection of quantum dots (QDs) in portable, disposable devices avoiding the solution transfer after the acidic digestion of the nanocrystals. Use of magnetoelectrochemistry to enhance the mass transfer to the electrode and improve the quantum dots detection. These approaches have been employed for the determination of celiac disease biomarkers in serum samples.
- Novel electrochemical methods for the detection of quantum dots exploiting the unique surface properties of these nanocrystals. We have discovered the selective electrodeposition of silver on the quantum dots or the stabilization of electrogenerated copper species by these nanoparticles. These surface processes are extremely sensitive and can be applied to the detection of nanoparticles with remarkable limits of detection. They are very selective and their control allows the generation of Janus nanoparticles (i.e. with two different faces: Ag/QD).
- Development of new mesoporous nanoparticles (titanium phosphate) with the ability to introduce different electroactive metals. We were able to enhance the introduction of the metallic amount into the nanoparticle and their posterior extraction to increase the detection sensitivity. Different electroactive metals could be loaded into the nanoparticles, being possible their application to multiplexing biosensing.
Cost-effective analytical devices for point-of-need sensing
The development of cost-effective disposable analytical devices for point-of-need sensing may contribute to the improvement on the response time and cost for events as different as a heavy metal contamination in a river or monitoring the crops maturity to choose the best moment to harvest.
- Detection of mercury with disposable devices modified with nanohybrid materials to improve the electron transfer and the detection efficiency.
- Towards “zero-cost” analysis using paper electrodes as sensing devices. Development of paper-based electrodes for the detection of heavy metals directly on the container used to collect the sample. Work in collaboration with Prof. Charles Henry (Colorado State University).
- Novel reusable electrode platforms with disposable paper working electrodes and shared counter and reference electrodes (Invention protected by spanish patent).
- Copper or nickel nanostructured devices with remarkable stability for the electrocatalytic detection of sugars in clinical and food samples.
Fundamental electrochemistry on disposable devices
Although the utilization of disposable electrochemical devices has an eminently applied character, the study of the electrochemical behaviour of these devices could be relevant to improve their properties and applications. One of our previous research lines has been the characterization of disposable electrodes fabricated with different carbon materials:
- I spent a short-period secondment in the University of Warwick (UK) under the supervision of Prof. Patrick Unwin to study the localized electrochemical activity of graphite screen-printed electrodes using state-of-the-art scanning electrochemical cell microscopy (SECCM), being able to correlate the electrochemistry with the microscopic structural properties.
- Electrochemical characterization of screen-printed electrodes modified with ordered mesoporous carbon or electrochemically reduced graphene oxide (ERGO). In a work performed in collaboration with Dr. Rosa Menéndez (current president of the Spanish National Research Council), we found that the presence of residual functional groups could influence the electron transfer of the graphene materials.
In situ dynamic spectroelectrochemistry
Combining electrochemical and optical techniques multiply the information that can be in situ obtained from chemical systems. Integrated instrumentation for simultaneous electrochemical and optical data recording with high time-resolution allows to study dynamic and transient processes. I have research experience with different dynamic spectroelectrochemical techniques:
- Raman spectroelectrochemistry: development of a quasi-universal method for the in situ activation of metallic screen-printed electrodes with simultaneous SERS detection. This method allows to obtain substrates with a singular structural composition where the SERS activity is highly enhanced. This work was performed in collaboration with Prof. Alvaro Colina from Universidad de Burgos (Spain).
- Luminescence spectroelectrochemistry: study in real-time of the behaviour of electroluminochromic species on different electrode substrates (carbon, gold, silver) in order to investigate the effect of the structure and composition of the substrate on the electro-optical properties, which could have interest in the development of novel optical devices. We have also applied this technique to indirect sensing of species difficult to measure by the individual techniques such as chloride in sweat samples.