Research

Overview

LNCE develops synthetic approaches to tailor-make novel nanomaterial platforms with the aim of advancing the knowledge in energy research. To achieve control on composition, morphology and interfaces, we use colloidal chemistry, which is one of the most powerful solution-based bottom-up approaches to nanomaterials. To verify mechanistic hypothesis and to assess the relevant materials properties that we are seeking for, we implement our materials into proof-of-concept devices.
Currently, we are focusing on energy storage into chemical bonds, namely artificial photosynthesis. Transforming water, CO2 and solar energy into fuels is a promising approach to reduce the global dependence on fossil fuels and thus to move towards a more sustainable society. Materials and phenomena to carry this transformation in an efficient manner have yet to be discovered. Our research aims at providing new solutions by means of colloidal chemisty.

research overview

Multinary Metal Oxides and Their Heterostructures

Achieving fine control over the composition and stoichiometry of multi-elements oxides is a non trivial challenge that chemists and materials scientists are facing in different applications areas, from  batteries to fuels cell and resistive switching memories. In the context of solar-to-energy conversion, multi-cations oxides are receiving attention as light absorbers to drive water oxidation, as they are stable under the harsh environment required by this reaction. LNCE is contributing to advance the field by devising robust synthetic approaches to complex oxide materials, so to establish meaningful structure/properties relationships and to validate theoretical predictions.

Some examples of our research on this topic:

metaloxide1 metaloxide2

We have learned how to selectively  position nitrogen dopants in TiO2 nanourchins and correlate the lattice position of the dopant to the photoelectrochemical properties. (J. Phys. Chem. 2015)

We have synthesized antimony-alloyed bismuth vanadate, a new light absorber, in a wide compositional range, using colloidal nanocrystals as nucleation seeds. (Adv. Mater. 2015)
metaloxide3
We have reported a novel solution-based route to nanostructured bismuth vanadate (BiVO4) that facilitates the assembly of BiVO4/metal oxide (TiO2, WO3, and Al2O3) nanocomposites. These nanocomposites serve as platforms to understand and to direct chanrge separation, transport and photoelectrochemical efficiency. (Nano Lett. 2015)

Electrocatalytically-Active Nanocrystals

Defining design principles to precisely control nanocrystals composition and morphology is scientifically interesting and technologically important at the same time. Catalytic properties are strongly impacted by the catalyst size and shape. Furthermore, at the nanoscale new properties may arise which deviate from the bulk behavior. LNCE is exploiting such advantages of colloidal chemistry to build solid relations between catalyst structure and its activity and to gain deeper insights into the mechanisms for electrocatalytic CO2 conversion (CO2RR).

Cu nanocubes for CO2RR

We have synthesized colloidal copper nanocrystals with different sizes and shapes and investigated their behaviour as CO2RR electrocatalysts. The unique size-dependent trend in the catalytic activity of the copper cubes suggests the key role played by edge sites in CO2RR. (Angew. Chem. Int. Ed. 2016)

Nanocrystal Assembly into Multifunctional Hybrids

Energy devices require materials able to transport mass, charge and energy during operation. Such complexity is hard to meet by single component materials. Therefore, the demand for hybrid multifunctional materials has been increasing in different applications.
LNCE is assembling colloidal nanocrystals with building blocks belonging to intrinsically different classes of materials, such as polymers or metal organic frameworks. The goal here is to establish novel synthetic schemes to achieve an exquisite control and tunability of these hybrid materials across multiple lengthscales by understanding and manipulating the nucleation and growth kinetics.

We have learned to precisely match the dissolution rate of Cu nanocrystals and the Cu-MOF-74 crystallization kinetics to construct uniform [email protected] hybrids.

(Chem. Mater. 2016)

QD-alumina CsPbBr3 quantum dots (QDs) were stabilized towards water, light, and heat by embedding them in an alumina matrix (AlOx), which was deposited by atomic layer deposition. The interactions between the ALD precursors and the surface of the QDs are key to uniformly coat the QDs while preserving their optoelectronic properties.​

(Angew. Chemie. Int. Ed. 2017)