  Metal alloys hold the promise of providing hot carrier generation
distributions superior to pure metals in applications such as sensing,
catalysis and solar energy harvesting. Guidelines for finding the optimal alloy
configuration for a target application require understanding the connection
between alloy composition and hot carrier distribution. Here we present a
DFT-based computational approach to investigate the photo-generated hot carrier
distribution of metal alloys based on the joint density of states and the
electronic structure. We classified the metals by their electronic structure
into closed d-shell, open d-shell, p-block and s-block elements. It is shown
that combining closed d-shell elements enables modulating the distribution of
highly energetic holes typical of pure metals but also leads to hot carrier
production by IR light excitation and the appearance of highly energetic
electrons due to band folding and splitting. This feature arises as an emergent
property of alloying and is only unveiled when the hot carrier distribution
computation takes momentum conservation into account. The combination of closed
d-shell with open d-shell elements allows an abundant production of hot
carriers in a broad energy range, while alloying a closed d-shell elements with
an s-block element opens the door to hot electron distribution skewed toward
high energy electrons. The combination of d-shell with p-block elements results
in moderate hot carrier distribution whose asymmetry can be tuned by
composition. Overall, the obtained insights that connect alloy composition,
band structure and resulting carrier distribution provide a toolkit to match
elements in an alloy for the deliberate engineering of hot carrier
distribution.
