David Zitoun's Lab – INORGANIC CHEMISTRY AND NANOMATERIALS FOR ENERGY LAB

Bar Ilan University, Department of Chemistry – Bar Ilan Institute of Nanotechnology and Advanced Materials (BINA)

DAVID ZITOUN'S INORGANIC CHEMISTRY AND NANOMATERIALS FOR ENERGY LAB

Prof. David Zitoun is Full Professor and head of the Department of Chemistry and a member of the Nano-Energy and Nano-Materials Center at the Bar-Ilan Institute of Nano-technology and Advanced Materials (BINA).

My research group synthesizes nanoscale materials and investigates their applications to devices (mainly electrochemical and electrical). Towards this goal, the group investigates the synthesis of nanoscale objects, their integration in nano-, micro- or macro-electrodes and develops operando experimental techniques to gain knowledge on the phenomena at work during device operation.

The nanoscale objects reveal interesting phenomena which differ from the bulk materials and are mainly highlighted by the predominance of surfaces, the phase changes and the metastable arrangement of atoms. These nanoscale objects display unique electromagnetic and chemical properties. These effects are observed in quantum dots, plasmonic, magnetic and catalytic nanoparticles.

The main research efforts of the lab consist in the wet chemical synthesis of nanoscale objects and metastable nanostructures, mainly based on transition metals. It applies to electrode materials for batteries, to electrocatalysts for fuel cells, water splitting and redox-flow batteries and to electrical sensors.

The lab has strong collaborations with other disciplines (physics, engineering, life sciences), with the industry and with international labs (US, European Union, China, South-Korea).

RESEARCH TOPICS

Redox-flow batteries

The future of energy depends on the ability of the electrical grid to accept more variable renewable energy sources. In the next decades, the world will need 500 TWh of electricity storage. The electrochemical storage of energy in abundant and cheap chemicals can in principle be achieved in redox-flow batteries. We develop bromine based redox-flow batteries with an innovative approach towards long-lasting, low-cost components.

Electrolyzers

One of the bottlenecks towards the successful implementation of alternative energies is the lack of methods for sustainable generation of hydrogen fuel (energy carrier). Given that water will be at the very least an important component of the hydrogen production feedstock, sustainable catalysts are needed for the electrochemical generation of hydrogen from water.

Fuel Cells

Alkaline exchange membrane fuel cells (AEMFCs) have received significant interest in recent years, because this technology has the potential of overcoming cost barriers of polymer electrolyte fuel cells (PEMFCs), since the basic environment of the anion exchange membranes allows the use of less expensive electrocatalysts and low-cost metal hardware.

Batteries

The main driving force for the syntheses of materials derives from the need for technological game-changers, specifically for electrochemical storage and conversion of energy. The needs for higher energy density and faster charge in batteries are highlighted by the continuous emergence of novel electrode materials and methods for electrode fabrication processes. In general, the development of in-situ (or operando) characterization techniques provides uniquely valuable information about chemical processes since the interpretation of ex-situ measurements can only offer a partial picture of the chemical reactions.concentration. We do develop fast and selective sensors based on nanoparticles assemblies.

Sensing

Sensors can detect dangerous chemicals with relatively good accuracy but suffer from slow response and mediocre selectivity. In particular, the advent of hydrogen economy brings new challenges in terms of safety and sensing with a need for fast and low-cost monitoring of hydrogen concentration. We do develop fast and selective sensors based on nanoparticles assemblies.

Fundamental challenges

The advancement of chemical synthesis of complex nanoparticles is of key importance to discover novel physico-chemical behaviors. On the other hand, the rational design of active materials has sometimes reached its limits and external stimuli can benefit to the chemical activity. For instance, it has long been forecast that magnetic or plasmonic heating (or in some cases hot electrons) could leverage the use of earth-abundant electrocatalysts and provide sustainable alternatives to precious group metals. While the demonstration of these effects is still a challenge, the fabrication of devices working on these principles is a completely new field. In parallel, the quest for new materials will be achieved by combinatorial research. The tools are now in development in the laboratory for solid-state batteries, water splitting and gas sensing. The combinatorial requires high throughput synthesis and characterization and, finally, the development of data-mining specific tools.