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The formation of sulfide and oxide films on copper (Cu) was studied in chloride solutions with and without added borate and sulfide. Electrochemical experiments demonstrated that Cu sulfide (Cu2S) films formed at considerably lower potentials than oxides (Cu2O/CuO) films. The growth of Cu2S was controlled by a combination of sulfide transport to the reacting Cu surface and the competition between SH− and Cl− ions for adsorption sites on the Cu surface. Scanning electron microscopy on focused ion-beam cut cross sections demonstrated that the films were porous and not passive. At more positive potentials, Raman spectroscopy and X-ray photoelectron spectroscopy demonstrated that the formation of oxide films, likely with the formation of a passive oxide film, dominated over anodic dissolution of Cu as CuI chloride complexes when the borate to chloride concentration ratio was sufficiently high. If pitting is to occur on Cu, it will require oxide not sulfide film growth. [ABSTRACT FROM AUTHOR]

The article discusses the properties of copper sulfide films on copper grown by electrochemical methods studied using electrochemical impedance spectroscopy. Topics include porosity, deposition, and oxidizing potentials.

Significant global investments are being made into smart urban mobility technologies but there is limited evidence of the potential co-benefits for reducing carbon emissions, environmental pollutants and human health impacts at scale and over the long-term. We use conservative estimates of vehicle electrification and grid decarbonisation to focus specifically on information and communication technology (ICT) interventions. In doing so, we develop a smart mobility framework focusing on more efficient road networks and driving behaviour enabled by rapid ICT deployment. Our scenarios suggest that a combination of ambitious policy measures aimed at smoothing traffic speeds as well as improving driver behaviour in urban areas could reduce carbon emissions for cars ∼29% saving ∼7 MtCO _2 and for vans ∼33% saving ∼3 MtCO _2 by 2050. Potential reductions in nitrogen oxides and particulate matter 2.5 for cars are ∼22% and vans ∼10% and ∼16% respectively. We use human toxicological classification of air pollution (HCA) to assess the potential damage on human health and our scenarios suggest an upper range of ∼23% and ∼30% reductions in HCA by 2050 for cars and vans respectively. Using conservative cost values, we estimate damage costs could be avoided from car emissions range from ∼£42–£130 million and vans ∼£89–£163 million per year. However, our baseline projections indicate that emissions and damage costs avoided from passenger cars could be partially offset by growing demand for urban van delivery and freight services that are currently outpacing improved fuel and emissions performance of the vehicle stock. This may reflect broader lifestyle and consumer trends towards on-line shopping, food and delivery services, which warrants further investigation.