Band Edge Engineering of Hydroxide Nanoparticles for Semiconductor and Electrochemical Applications

Band Edge Engineering of Hydroxide Nanoparticles for Semiconductor and Electrochemical Applications

Matthias J. Young, Nicholas M. Bedford, Tatyana Kiryutina, Taylor J. Woehl

The band edge properties of a material largely determine its viability as an active material for optoelectronic, photochemical, and electrochemical applications, among others. Layered double hydroxides (LDHs) are a class of semiconducting materials which have garnered recent interest due to their (photo)catalytic, electrochemical, and corrosion-resistant properties. In this work, we examine the effect of cation composition on the band gap and band edge positions in a range of LDH structures. We employ atomistic materials simulations to model the band edge properties of LDH structures with structures comprised of various +2 cations (e.g. Co,Mg,Ni) and +3 cations (e.g. Al,Cr,V).This modelling is compared and contrasted with the experimental optical properties of LDH nanoparticles. We also explore the effect of substitutional dopants and point defects on the band edge properties of Mg-Al LDHs. LDH nanoparticles are synthesized using coprecipitation and their structural properties are evaluated using TEM and synchrotron characterization techniques. A subset of these LDH structures are also evaluated for their electrochemical and optoelectronic properties.