Disputation: Kaiqi Xu

Msc. Kaiqi Xu at the Department of Chemistry, Faculty of Mathematics and Natural Sciences, is defending the thesis   «Artificial photosynthesis – Advanced nanomaterials and use of biocatalysts for novel photoelectrochemical cells» for the degree of Philosophiae Doctor.


Bildet av kandidaten.


The University of Oslo is closed at the moment due to the Corona Pandemic. The Disputation will therefore be live streamed using Zoom. 
The Chair of Defense will lead the Disputation and the Defense technician will solve technical issues.

Ex auditorio questions: The Chair of Defense will invite the audience to ex auditorio questions. These can be asked orally, by clicking "Participants - Raise hand" in the Zoom menu. The Zoom-host will grant you to speak in the meeting.


Click here to join the disputation


Download Zoom here


Order the Dissertation as PDF using this email address (with name of the Candidate): a.c.gartner@kjemi.uio.no


Trial lecture

"Electron transfer at metal and semiconductor electrodes"

Friday April 24th. 10:15 AM, Zoom

Click here to join the trial lecture

Conferral summary

CO2-utnyttelse kan gi et viktig bidrag til en karbonfri energiøkonomi dersom fangst og konvertering av CO2 kan gjøres effektivt med fornybar energi. Gjennom dette prosjektet har vi demonstrert hvordan en bio-katalysator (enzym) kan kombineres med mer tradisjonell kjemiteknikk for å oppnå dette. Vi koblet Ta3N5 nanorørene som fotoanode med et optimalisert enzym oksygen-tolerant format-dehydrogenase (FDH) - i en soldrevet fotoelektrokjemisk celle som konverterer CO2 og vann til maursyre med nær 100% faradaisk effektivitet.

CO2 utilization is considered a key player in a carbon-free energy economy, emphasising the importance of CO2 capture and conversion. We have successfully demonstrated how a bio-catalyst (enzyme) can be coupled with traditional chemical engineering for this purpose. To approach this, a stable, highly photo-active material - Ta3N5 nanotubes - has been synthesized and tested in a photoelectrochemical cell. It reaches close to its theoretical performance in photo-assisted water splitting. We then coupled the Ta3N5 nanotubes as the photoabsorber together with an optimised enzyme - formate dehydrogenase (FDH) - in a photoelectrochemical cell. The aim is to mimic natural photosynthesis to reduce CO2 into a valuable chemical form – formic acid. A solar-driven reduction of CO2 and water to formic acid at close to 100% faradaic efficiency has been reached.


Published Sep. 10, 2020 10:08 AM - Last modified Sep. 10, 2020 10:16 AM