X-rays with excellent penetration power and high
chemical sensitivity are suited to understand heterogeneous
materials. In a new report on Science Advances, A. Pattammattel,
and a team of scientists at the National Synchrotron Light Source
in New York, U.S., described nanoscale chemical speciation by
combining scanning nanoprobe and fluorescence-yield X-ray
absorption near-edge structure—known as nano-XANES. The team showed
the resolving power of nano-XANES by mapping states of iron of a
reference sample composed of stainless steel and hematite
nanoparticles using 50-nanometer scanning steps. Using nano-XANES,
the team also studied the trace secondary phases of lithium iron
phosphate (LFP) particles and noted the individual
iron(Fe)-phosphide nanoparticles within the pristine lithium iron
phosphate, while partially delithiated particles showed
Fe-phosphide nanonetworks. This work on nano-XANES highlight the
contradictory reports on iron-phosphide morphology within the
existing literature and will bridge the capability gap of
spectromicroscopy methods to provide exciting research
opportunities.