  How surface chemistry influences reactions occurring thereupon has been a
long-standing question of broad scientific and technological interest for
centuries. Recently, it has re-emerged as a critical question in a
subdiscipline of chemistry - electrochemistry at heterointerphases, where the
answers have implications for both how, and in what forms, humanity stores the
rising quantities of renewable electric power generated from solar and wind
installations world-wide. Here we consider the relation between the surface
chemistry at such interphases and the reversibility of electrochemical
transformations at a rechargeable battery electrode. Conventional wisdom holds
that stronger chemical interaction between the metal deposits and electrode
promotes reversibility. We report instead that a moderate strength of chemical
interaction between the deposit and the substrate, neither too weak nor too
strong, enables highest reversibility and stability of the plating/stripping
redox processes at a battery anode. Analogous to the empirical Sabatier
principle for chemical heterogeneous catalysis, our finding arises from the
confluence of competing processes - one driven by electrochemistry and the
other by chemical alloying. Based on experimental evaluation of metal
plating/stripping systems in battery anodes of contemporary interest, we show
that such knowledge provides a powerful tool for designing key materials in
highly reversible electrochemical energy storage technologies based on
earth-abundant, low-cost metals.
