@article{KogikoskiJuniorDuttaBald2021,
  author    = {Kogikoski Junior, Sergio and Dutta, Anushree and Bald, Ilko},
  title     = {Spatial separation of plasmonic hot-electron generation and a hydrodehalogenation reaction center using a DNA wire},
  series = {ACS nano},
  volume    = {15},
  journal   = {ACS nano},
  number    = {12},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {1936-0851},
  doi       = {10.1021/acsnano.1c09176},
  pages     = {20562 -- 20573},
  year      = {2021},
  abstract  = {Using hot charge carriers far from a plasmonic nanoparticle surface is very attractive for many applications in catalysis and nanomedicine and will lead to a better understanding of plasmon-induced processes, such as hot-charge-carrier- or heat-driven chemical reactions. Herein we show that DNA is able to transfer hot electrons generated by a silver nanoparticle over several nanometers to drive a chemical reaction in a molecule nonadsorbed on the surface. For this we use 8-bromo-adenosine introduced in different positions within a double-stranded DNA oligonucleotide. The DNA is also used to assemble the nanoparticles into nanoparticles ensembles enabling the use of surface-enhanced Raman scattering to track the decomposition reaction. To prove the DNA-mediated transfer, the probe molecule was insulated from the source of charge carriers, which hindered the reaction. The results indicate that DNA can be used to study the transfer of hot electrons and the mechanisms of advanced plasmonic catalysts.},
  language  = {en}
}
@article{DuttaSchuermannBalko2020,
  author    = {Dutta, Anushree and Sch{\"u}rmann, Robin Mathis and Balko, Ilko},
  title     = {Plasmon mediated decomposition of brominated nucleobases on silver nanoparticles},
  series = {The european physical journal D},
  volume    = {74},
  journal   = {The european physical journal D},
  number    = {19},
  publisher = {Springer},
  address   = {Berlin},
  issn      = {1434-6079},
  doi       = {10.1140/epjd/e2019-100115-1},
  year      = {2020},
  abstract  = {The localized surface plasmon resonances (LSPRs) of silver nanoparticles (AgNPs) give rise to the generation of so called hot electrons and a high local electric field enhancement, which enable an application of AgNPs in different fields ranging from catalysis to sensing. Hot electrons generated upon the decay of LSPRs are transferred to molecules adsorbed on the surface of the NPs and trigger chemical reactions via dissociative electron attachment (DEA). Herein, we report on the hot electron induced decomposition of the brominated nucleobases - 8-bromoadenine, 8-bromoguanine, 5-bromocytosine and 5-bromouracil on laser illuminated AgNP surfaces. Surface enhanced Raman scattering (SERS) spectra of all canonical nucleobases and their brominated analogues have been recorded at different laser illumination times, and for the very first time we present SERS measurements of 8-bromoguanine and 5-bromocytosine. Reaction products have been identified by their vibrational fingerprint revealing the cleavage of the carbon bromide bond in all cases even under mild illumination conditions. These results indicate that the well-known reactions from DEA experiments in the gas phase (i) are also taking place on nanoparticle surfaces under ambient conditions, (ii) can be monitored by SERS, and (iii) are also of importance in analytical SERS applications involving electrophilic molecules, as the bands originating from reaction products need to be identified.},
  language  = {en}
}
@article{DuttaSchuermannKogikoskiJunioretal.2021,
  author    = {Dutta, Anushree and Sch{\"u}rmann, Robin and Kogikoski Junior, Sergio and Mueller, Niclas S. and Reich, Stephanie and Bald, Ilko},
  title     = {Kinetics and mechanism of plasmon-driven dehalogenation reaction of brominated purine nucleobases on Ag and Au},
  series = {ACS catalysis / American Chemical Society},
  volume    = {11},
  journal   = {ACS catalysis / American Chemical Society},
  number    = {13},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {2155-5435},
  doi       = {10.1021/acscatal.1c01851},
  pages     = {8370 -- 8381},
  year      = {2021},
  abstract  = {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.},
  language  = {en}
}