Interface-driven energy-independent charge extraction in GaN photocatalysts.

ABSTRACT: Ultrafast charge transfer dynamics are key to photocatalytic efficiency, governing energy relaxation and surface reactivity. However, the temporal evolution of carrier energy landscapes following photoexcitation, particularly at complex metal/semiconductor interfaces, remains poorly understood. Here, we present a surface- and energy-resolved investigation of ultrafast electron dynamics across bare and Pt-modified gallium nitride (GaN) surfaces using time-resolved two-photon photoemission spectroscopy. We show that photogenerated electrons rapidly thermalize to the conduction band minimum and undergo sub-picosecond trapping in nitrogen-vacancy-related surface states. Surface modification with Pt suppresses these trapping channels and introduces an energy-independent ultrafast electron trans

SUBMITTER: Gao Y 

PROVIDER: S-EPMC12920748 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature