TY  - JOUR
A1  - Dutta, Anushree
A1  - Schürmann, Robin
A1  - Kogikoski Junior, Sergio
A1  - Mueller, Niclas S.
A1  - Reich, Stephanie
A1  - Bald, Ilko
T1  - Kinetics and mechanism of plasmon-driven dehalogenation reaction of brominated purine nucleobases on Ag and Au
JF  - ACS catalysis / American Chemical Society
N2  - Plasmon-driven photocatalysis is an emerging and promising application of noble metal nanoparticles (NPs). An understanding of the fundamental aspects of plasmon interaction with molecules and factors controlling their reaction rate in a heterogeneous system is of high importance. Therefore, the dehalogenation kinetics of 8-bromoguanine (BrGua) and 8-bromoadenine (BrAde) on aggregated surfaces of silver (Ag) and gold (Au) NPs have been studied to understand the reaction kinetics and the underlying reaction mechanism prevalent in heterogeneous reaction systems induced by plasmons monitored by surface enhanced Raman scattering (SERS). We conclude that the time-average constant concentration of hot electrons and the time scale of dissociation of transient negative ions (TNI) are crucial in defining the reaction rate law based on a proposed kinetic model. An overall higher reaction rate of dehalogenation is observed on Ag compared with Au, which is explained by the favorable hot-hole scavenging by the reaction product and the byproduct. We therefore arrive at the conclusion that insufficient hole deactivation could retard the reaction rate significantly, marking itself as rate-determining step for the overall reaction. The wavelength dependency of the reaction rate normalized to absorbed optical power indicates the nonthermal nature of the plasmon-driven reaction. The study therefore lays a general approach toward understanding the kinetics and reaction mechanism of a plasmon-driven reaction in a heterogeneous system, and furthermore, it leads to a better understanding of the reactivity of brominated purine derivatives on Ag and Au, which could in the future be exploited, for example, in plasmon-assisted cancer therapy.
KW  - hot-electrons
KW  - plasmon-driven catalysis
KW  - fractal kinetics
KW  - brominated
KW  - purines
KW  - SERS
KW  - hole scavengers
Y1  - 2021
U6  - https://doi.org/10.1021/acscatal.1c01851
SN  - 2155-5435
VL  - 11
IS  - 13
SP  - 8370
EP  - 8381
PB  - American Chemical Society
CY  - Washington
ER  -