Hydrogen is often considered the fuel of the future because its combustion liberates only water and no harmful greenhouse gases. In addition, hydrogen is an unlimited and sustainable resource on Earth, if it can be generated efficiently and ecologically from water, rather than via steam reformation of hydrocarbons. One of the most promising technologies is the photoelectrochemical production of hydrogen from water. Despite significant progress over the last decade, the electrolysis of water requires significant overpotentials and Ieads to the formation of undesirable by-products, such as peroxides and superoxide radicals, which are known to poison the photocatalyst, thereby reducing its lifetime. Whilst organic spintronics are explored to develop low power devices for information processing, the importance of electronic spin control in photoelectrochemical processes has been largely neglected. This project will explore the possibility to develop organic spin-filters, which will make it possible to control reaction pathways by preventing the formation of radical intermediates with opposite spins, thereby restraining the production of undesirable side products. The control of chemical kinetics through spin selection can have extraordinary consequences in controlling a particular redox process and presents a radical departure from traditional methods of electrochemical reaction rate control. We aim to examine the effect of the spin on the photogenerated charge carriers’ transfer and recombination in hybrid photocatalytic nanostructures. This will be achieved by studying how the magnetic field and the nanostructure interact and affect the photoelectrochemical current of selected systems. Can we tune the photogenerated charge carrier transport and recombination processes in hybrid nanostructured systems by inducing spin changes under an applied magnetic field? And can we therefore control the photocatalytic performance of these systems?
To create hybrid photocatalytic nanostructures, the successful candidate will design a system with photoactive nanoparticles that will be anchored to spin-selective organic molecules. They will shape a self-assembled layer of the produced hybrid nanostructures that can be easily attached to an electrode of a ferromagnetic material, such as nickel. This will allow them to impose a magnetic field on the system using an external permanent magnet and explore whether the electrons’ spin orientation affects the photocharge carrier transport and lifetime in such hybrid systems, and to what extent. This is a very pioneering project and will undoubtedly lead to great advances and exciting results in the area of energy materials.
The successful candidate will be supervised by Dr. Jorge Sobrido (QMUL) and Dr. Schroeder (UCL), and co-supervised by Dr. Briscoe (QMUL). They will design the chiral photoactive systems. This is a truly multidisciplinary project that involves: (i) Synthesis of chiral semiconductors to act as spin-filter (Organic Chemistry); (ii) Anchoring of the spin-filter to the metallic electrode surface and functionalising them with photoactive species as catalytic sites (Surface Chemistry and Inorganic Chemistry); (iii) Photoelectrochemical characterisation of the chiral hybrid systems in an external magnetic field (Photophysics and Electrochemistry). This project would suit candidates with a background on Chemistry and Materials Science, with knowledge of semiconducting materials and enthusiasm for energy applications.
QMUL Research Studentship Details
Available to Home/EU & International Applicants.
Full Time programme only
Applicant required to start in September/October 2018
The studentship arrangement will cover tuition fees and provide an annual stipend for up to three years (Currently set as £16,553 in 2017/18).