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We report the design and performance of a 3-electrode device for real time in situ scanning transmission X-ray microscopy studies of electrochemical processes under both static (sealed, non-flow) conditions and with a continuous flow of electrolytes. The device was made using a combination of silicon microfabrication and 3D printing technologies. The performance is illustrated by results of a study of copper deposition and stripping at a gold working electrode. X-ray absorption spectromicroscopy at the Cu 2p edge was used to follow the evolution as a function of potential and time of the spatial distributions of Cu(0) and Cu(i) species electro-deposited from an aqueous solution of copper sulphate. The results are interpreted in terms of competing mechanisms for the reduction of Cu(ii).

Titanium–6 aluminium–4 vanadium (Ti64) alloy was modified to a hydrophilic, cytocompatible, antibacterial and bioactive surface via a simple cost effective chemical treatment method. A fine porous network structure of sodium hydrogen titanate (SHT) was formed on the Ti64 alloy surface by using sodium hydroxide treatment. The incorporated Na+ ions are replaced by Ag+ ions by a subsequent silver nitrate treatment. Contact angle measurement indicated that the silver containing Ti64 alloy surface is hydrophilic at lower silver concentration. The antibacterial study of the thus prepared sample against Staphylococcus aureus confirmed the bacterial resistance of the Ti64 alloy. As evident from the AAS result, the sustained release of Ag into the culture medium results in antibacterial activity. Cytocompatibility studies on MG63 cell lines showed above 80% cell viability and also good cell attachment. This confirmed the nontoxic behavior of the present optimized silver concentration on the Ti64 surface for MG63 cells. In vitro bioactivity of the silver containing Ti64 sample in simulated body fluid showed bone-like apatite formation and the apatite-forming ability is not affected by Ag concentration or by heat treatment. Taken together, this surface modification study adds further information to our knowledge on the development of a bioactive Ti64 alloy with hydrophilicity, antibacterial activity and biocompatibility that may have considerable potential application as orthopedic and dental implants.