A device was developed that converts carbon dioxide, water and sunlight into sustainable fuels, efficiently and cheaply. The European consortium led by the Catalan Institute of Chemical Research achieved this by taking inspiration from the photosynthetic function of plants. The next step is to demonstrate its industrial viability.
The results of the project are now added to the diversification of energy sources that currently tends to A LEAFcoordinated by José Ramón Galán-Mascarós from the Catalan Institute of Chemical Research (ICIQ-CERCA) and in which scientific institutions from France, Germany, Italy and Switzerland also participate.
This research initiative on artificial photosynthesis, one of the largest funded by the European Commission, consists of an autonomous device capable of converting carbon dioxide (COtwo) and water (HtwoO) into fuels using sunlight, similar to how plants photosynthesize.
The innovative cell the team developed provides solar-to-fuel efficiency of over 10%, achieving world record current densities without the use of critical materials.
This shows that sustainability and high productivity can also be achieved with low-cost and scalable materials, according to the researchers.
Production of sustainable fuels: hydrogen
In addition, they present the new concept of hydrogen production (Htwo) and an element or ‘format’ to store it simultaneously, the latter being used to generate it later in the absence of sunlight.
Thus, this solution allows for the first time a continuous production (24/7) of hydrogen by means of an artificial leaf device.
“The A-LEAF was a truly interesting and challenging project, and ending up with a highly efficient prototype was icing on the cake.“, says professor Javier Pérez-Ramírez from ETH in Zurich.
This approach was validated in a compact electrochemical flow cell architecture, with electrodes based on copper-sulfur (Cu-S) and nickel-iron-zinc oxide (Ni-Fe-Zn, for reduction of protons and COtwo and oxygen evolution reactions, respectively) supported by gas diffusion electrodes, integrated into a low-cost silicon photovoltaic module.
The cell operates at a current density of about 17 milliamps per square centimeter (mA cm−2) and a voltage of 2.5 volts (stable for more than 24 hours and during on and off operations), providing a format productivity greater than 190 micromoles per square meter per second (μmol h−1 cm−2).
The results of the study
Thus, the results of this study pave the way for the implementation of affordable artificial leaf systems in the future energy scenario, providing a sustainable solution to the great challenge of achieving the energy transition and transforming the current centralized model into a distributed one.
“This is the first example of an artificial leaf with an order of magnitude greater efficiency than the natural leaf. This big step would not have been possible without the close interaction and collaboration of many research centers with multidisciplinary competences. We are now looking to implement the next step of full-scale prototyping to demonstrate industrial feasibility.”, explains Professor Siglinda Perathoner from the Università degli Studi di Messina (Italy).
The A-leaf technology is ready for further scale and optimization, with the ultimate goal of building an artificial tree, thus supporting the dream of a sustainable future, according to the authors, who publish their study in Energy and Environmental Sciences.
“Beyond the productivity numbers, our biggest success was bringing together a European team of world leaders in their different research areas to work together with a common goal: to prove that an artificial leaf can also work when built exclusively with accessible materials, offering a performance record. in this cutting-edge technology”, concludes Galán-Mascarós.
Galán-Mascarós, JR “An artificial leaf device constructed with earth-abundant materials for combining Htwo production and storage as a format with efficiency > 10%” Energy and Environmental Sciences (2023)