Iodine Solution Treatment in Nonpolar Solvents as a Facile Approach to Improve the Morphology and Photostability of Perovskite Films.

We propose a new, simple, and easily implemented approach to improve the morphology of thin films of lead halide perovskites. A key feature of the approach is the controllable size increase of perovskite grains facilitated by polyiodides formed on the surface of the perovskite upon its treatment with iodine solutions in nonpolar solvents with the best results obtained for iodine solution in toluene saturated with MAI. Such a treatment demonstrated an increase in the average grain size of the films of up to 3.

Turning cellulose waste into electricity: hydrogen conversion by a hydrogenase electrode.

Hydrogen-producing thermophilic cellulolytic microorganisms were isolated from cow faeces. Rates of cellulose hydrolysis and hydrogen formation were 0.2 mM L(-1) h(-1) and 1 mM L(-1) h(-1), respectively.

Ultramicrosensors based on transition metal hexacyanoferrates for scanning electrochemical microscopy.

We report here a way for improving the stability of ultramicroelectrodes (UME) based on hexacyanoferrate-modified metals for the detection of hydrogen peroxide. The most stable sensors were obtained by electrochemical deposition of six layers of hexacyanoferrates (HCF), more specifically, an alternating pattern of three layers of Prussian Blue and three layers of Ni-HCF. The microelectrodes modified with mixed layers were continuously monitored in 1 mM hydrogen peroxide and proved to be stable for more than 5 h under these conditions.

Demonstration of hydrogenase electrode operation in a bioreactor.

This work describes the first step towards combination of the bioreactor with a starch-degrading microbial consortium and hydrogenase electrode (HE) in one unit for electricity generation. For this purpose, the bioreactor for microbial fermentation was designed with a set of electrodes (pH-sensor, Ag|AgCl reference electrode, Pt-electrode, and HE) inside the bioreactor. Potentials of all electrodes and H(2) accumulation were monitored in the system under the precise pH control.