Due to its low cost and suitable band gap, silicon has been studied as a photoanode material for some time. However, as a result of poor stability during the oxygen evolution reaction (OER), Si still remains unsuitable for any extended use. Ultra-thin titanium dioxide (TiO2) films have been used as protective coatings and are shown to enhance Si photoanode lifetime with added solar to hydrogen performance improvements through distancing the oxidation reaction away from the Si photoanode surface and improved charge transport through the anode. This study details the nucleation, growth chemistry, and performance of TiO2 thin films prepared via thermal and plasma enhanced atomic layer deposition (ALD) using both titanium isopropoxide and tetrakis(dimethylamido)titanium as the precursor material. The effect of post ALD treatments of plasma and air annealing was also studied. Films were investigated using photoelectrochemical cell testing to evaluate photoelectrochemical performance, and in-vacuum cycle-by-cycle x-ray photoelectron spectroscopy was used as the primary characterisation technique to study nucleation mechanisms and film properties contributing to improvements in cell performance. TiO2 grown by plasma enhanced ALD results in cleaner films with reduced carbon incorporation. However, despite increased carbon incorporation, thermally grown films showed improved photocurrent as a result of oxygen vacancies in these films. Post deposition annealing in a H2 ambient is shown to further improve photocurrent in all cases, while annealing in atmosphere leads to uniform film chemistry and enhanced photocurrent stability in all cases.

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This paper suggests that the contemporary feminist debate on relational autonomy is best understood as an attempt at ameliorative inquiry—the concept of autonomy is defined in order to secure political and theoretical advantages. Most theorists adopt some sort of constructionist, or relational, account precisely because of the political and theoretical advantages relational accounts are meant to offer. But there are also significant drawbacks to this approach. I argue that there are reasons to be skeptical of ameliorative inquiries into the concept of autonomy: first, the goals of inquiry have not been made explicit and may not be shared; second, because ameliorative inquiries are guided by unclear and unshared goals, the debate will continue to pull feminists in conflicting directions; and finally, the normative and aspirational nature of ameliorative inquiry unacceptably threatens the exclusion of some women from the category of autonomous agents.

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