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An electrochemical approach towards synthesis of highly active, stable and surface selective towards chlorine evolution reaction (CER) of (Zn, Ru)-doped TiO2 (Ru0.26Ti0.73Zn0.01Ox) for the purpose of electrochemical generation of KClO3 is demonstrated. The essential ingredients of this approach consists of (1) co-electrodeposition of Ru, Ti and Zn as metallic alloy and subsequent annealing to oxide (2) dissolution under electrochemically oxidative acidic environment of Ru and Zn-rich surface clusters having high selectivity towards oxygen evolution reaction (OER) leaving Ti-enriched structure that is more selective to CER and (3) using this electrocatalyst for KClO3 production under near-neutral pH conditions. Dissolution of Ru- and Zn enriched surfaces result in higher porosity and surface roughness. Furthermore, this electrochemical dissolution of (Zn, Ru)-rich surface results in electrocatalytic structure that is self-selective towards KClO3 formation with higher specific activity.

Electrochemical chlorine evolution reaction (CER) is one of the most important electrochemical reactions due to importance of Cl2 as an industrial chemical. However, electrochemical CER is bridled with parallel oxygen evolution reaction (OER) reducing the performance of anodic CER In this context, guiding principles behind enhancing the selectivity of CER is investigated experimentally and computationally in RuO2 doped with earth-abundant first-row-transition-metals (i.e. Ti, Fe, Mn, Co, Ni, Cu, Zn). Computational studies suggest that doping of metals having higher d-electrons than Ru in RuO2 tend to lower the binding strength of OER intermediates thereby increasing its overpotential. However, doping has less effect on the binding strength of monovalent CER intermediates resulting in higher CER selectivity. Computational studies suggest that Cu (d9)-doped RuO2 would show maximum CER selectivity and this is corroborated by experiments in acidic medium with electrodeposited Cu-doped RuO2 where 95% selectivity was obtained at a dopant concentration of 2%.

We modulate electron-hole separation at semiconductor junctions by stabilization of 'non-native' structures which are nanostructures whose discrete translational symmetry is different from that of the crystalline ground state. Four materials synthesis strategies involving click and colloidal chemistry are discussed and these methods can be potentially generalized to design a range of isomaterial and heteromaterial heterojunctions. The dynamics of electron-hole separation is demonstrated using density functional theory (DFT) which can be experimentally studied also using electrochemical impedance and photolumiscence spectroscopy.