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For the monitoring of heterogeneously catalyzed reactions surface enhanced Raman spectroscopy (SERS) has several advantages over other available techniques.The use of this requires that SERS activity as well as catalytic activity is combined into the same particle.A few obstacles make it challenging when designing suitable substrates.One important consideration to account for is the possibility of plasmon catalyzed side reactions.Localized surface Plasmon resonance (LSPR), encountered in for example silver and gold nanoparticles,is the main contributing factor of surface enhanced Raman signals.Combining the catalytically active particles with plasmonic SERS active particles can therefore give rise to the interference of plasmon catalyzed side reactions.Graphene has lately been found to have several interesting properties.One having the ability to enhance the Raman signals of analytes at the surface without being plamonic. In this thesis two different composites are investigated as substrates for reaction monitoring using Raman spectroscopy.The first composite is small sized silver nanoparticles dispersed on reduced graphene oxide and the second one is silver particles wrapped by graphene oxide and subsequently decorated by small sized silver nanoparticles.Both substrates are investigated for the silver catalyzed reduction of p-NTP to p-ATP by NaBH4.Apart from the reaction monitoring the thesis will also cover the synthesis strategy for these composites.The small.sized silver nanoparticles dispersed on reduced graphene oxide were synthesized by in-situ growth of silver nanoparticles onto graphene oxide.The material showed week SERS enhancing ability for R6G.However, the SERS activity was strong enough to successfully monitor the wished reaction with Raman spectroscopy. The wrapping of silver particles by grapheme oxide was achieved by using aminated silver particles and cracked graphene oxide.The wrapped particles were then treated with ammonia water which gave rise to small sized silver nanoparticles at the surface.The wrapping by graphene oxide was shown to quench the fluorescence signal, giving it advantage as a SERS substrate.When used for reaction monitoring however the obtained product was not the wished p-ATP but DMAB.DMAB is produced from p-NTP via a plasmon catalyzed reaction.However, when adding p-NTP to graphene oxide wrapped silver particles, with no small sized silver nanoparticles on the surface, tendency to form DMAB under laser radiation is showed to be much lower.That these results are in fact due to an enhancement in the LSPR signal when adding the small sized silver nanoparticles should be further confirmed.A possible explanation however is that the small sized silver nanoparticles "couple" with the silver core through the thin graphene oxide shield.