Optofluidic Microreactors for Advanced Photocatalysis

This PhD project explores the application of hollow-core photonic crystal fibres (HC- PCFs) as a novel and advanced characterization technique to monitor photocatalysis. The use of HC-PCFs as the core element of a newly developed characterisation platform has many benefits: HC-PCF’s light-guiding abilities and low-loss properties make absorp- tion spectroscopy based screening of reaction intermediates at low sample concentrations possible. The photoreduction of methyl viologen by carbon nanodots (CNDs) was studied and compared to theory by modelling reaction pathways. Oxidation states of cobaloximes, that are currently employed as molecular catalysts for solar hydrogen generation, could be studied and analysed in different pH environments. Furthermore, a novel enzyme based photocatalyst was characterized and its application in photocatalysis explored. With the resulting new insight and understanding of the reaction kinetics and reaction pathways, these nanoscale photocatalytic systems can be improved further to increase conversion efficiency. A functionalisation of HC-PCFs by depositing gold nanoparticles on the core wall lays the foundation towards surface-enhanced Raman sensing of reaction interme- diates. Spatial light modulation (SLM) techniques are applied to excite a wide variety of higher-order modes with well-defined cross-sectional intensity distributions inside the HC-PCF’s core. An automated fast-switching between inverted higher-order modes can in the future be exploited to enable pump-probe and diffusion/ adhesion measurements.

Name dc:type.qualificationname

Doctor of Philosophy (PhD)

Level dc:type.qualificationlevel

Doctoral

Grantor dc:publisher.institution

University of Cambridge

Year dc:date.issued

2019

Author dc:creator

• Koehler, Philipp

Advisors dc:contributor.advisor

• Euser, Tijmen
• Reisner, Erwin

• Optofluidics
• Photocatalysis
• Renewable Engery
• Hollow-Core Photonic Crystal Fibre
• Carbon Nanodots
• Spectroscopy
• Reaction Monitoring
• Microfluidics
• Heterogeneous Catalysis
• Homogeneous Catalysis

Licence

• https://www.repository.cam.ac.uk/bitstreams/00a98099-1585-46fe-9614-5a65ca82c017/download
• http://purl.org/NET/rdflicense/allrightsreserved

Language dc:language

eng

Author Identifier

0000-0002-8305-9598
0000-0002-7781-1616

OAI identifier oai:identifier

oai:www.repository.cam.ac.uk:1810/309321