From impurity ingress to high-performance doping: A perspective on atom probe tomography in energy materials

In this perspective article, we illustrate how advanced characterization, particularly atom probe tomography (APT), is crucial for detecting trace impurities, which can significantly affect a material's true properties. Drawing examples from studies focused on nanoelectrocatalysts, we show how contaminants can instead be turned into dopants to tune functionality. We then showcase how these concepts extend into other materials systems, including bulk thermoelectrics and 2D materials. Quantifying the distribution of impurities is critical for advancing the rational design of sustainable, next-generation materials, particularly as recycled, impurity-rich feedstocks will become the norm in a circular materials economy.