  Optoelectronic micro- and nanostructures have a vast parameter space to
explore for modification and optimisation of their functional performance. This
paper reports on a data-led approach using high-throughput single nanostructure
spectroscopy to probe > 8,000 structures, allowing for holistic analysis of
multiple material and optoelectronic parameters with statistical confidence.
The methodology is applied to surface-guided CsPbBr$_3$ nanowires, which have
complex and interrelated geometric, structural and electronic properties.
Photoluminescence-based measurements, studying both the surface and embedded
interfaces, exploits the natural inter-nanowire geometric variation to show
that increasing the nanowire width reduces the optical bandgap, increases the
recombination rate in the nanowire bulk and reduces the rate at the surface
interface. A model of carrier recombination and diffusion is developed which
ascribes these trends to carrier density and strain effects at the interfaces
and self-consistently retrieves values for carrier mobility, trap densities,
bandgap, diffusion length and internal quantum efficiency. The model predicts
parameter trends, such as the variation of internal quantum efficiency with
width, which is confirmed by experimental verification. As this approach
requires minimal a-priori information, it is widely applicable to nano- and
micro-scale materials.
