The role of crystal facets and disorder on photo-electrosynthesis

Abstract

We review how crystal facets, structural reconstructions and disorder impact the performance of electrodes for energy conversion.

Operando IR Optical Control of Localized Charge Carriers in BiVO4 Photoanodes

“…Among all native defects and dopants, oxygen vacancies in metal oxide photoelectrodes have been observed to play a critical role in transport and overall device efficiency . The absence of an oxygen atom in the oxide’s structure results in the formation of subvalent metallic sites, which can give rise to sub-band gap states responsible for n-type doping . Increasingly, research efforts have been devoted to exposing the underlying mechanisms behind the generation of mobile carriers and elucidating how vacancy control can affect and improve the process.…”

“…7,8 These charge localization processes impact PEC performance by limiting the attainable Fermi level splitting, 9 and consequently limit the reactions that can be photodriven, and by restricting charge movement inducing a transport bottleneck. 10 Importantly, slow transport hinders charge separation and prevents the accumulation of charges at the electrochemical interface, potentially influencing electron transfer steps and even altering reaction mechanisms. 11 Such broad impact highlights the importance of controlling charge transport pathways and has been the driver of intense research since the first reports of photoelectrochemical activity.…”