A review on photoelectrochemical cathodic protection semiconductor thin films for metals

Photoelectrochemical(PEC) cathodic protection is considered as an environment friendly method for metals anticorrosion. In this technology, a n-type semiconductor photoanode provides the photogenerated electrons for metal to achieve cathodic protection. Comparing with traditional PEC photoanode for water splitting, it requires the photoanode providing a suitable cathodic potential for the metal, instead of pursuit ultimate photon to electric conversion efficiency, thus it is a more possible PEC technology for engineering application. To date, great efforts have been devoted to developing novel n-type semiconductors and advanced modification method to improve the performance on PEC cathodic protection metals. Herein, recent progresses in this field are summarized. We highlight the fabrication process of PEC cathodic protection thin film, various nanostructure controlling, doping, compositing methods and their operation mechanism. Finally, the current challenges and future potential works on improving the PEC cathodic protection performance are discussed.

Conversion of CO2 by non-Thermal Inductively-Coupled Plasma Catalysis

CO2 decomposition is a very strongly endothermic reaction where very high temperatures are required to thermally dissociate CO2.Radio frequency inductively-coupled plasma enables to selectively activate and dissociate CO2 at room temperature.Tuning the flow rate and the frequency of the radio frequency inductively-coupled plasma gives high yields of CO under mild conditions.Finally the discovery of a plasma catalytic effect has been demonstrated for CO2 dissociation that shows a significant increase of the CO yield by metallic meshes.The metallic meshes become catalysts under exposure to plasma to activate the recombination reaction of atomic O to yield O2,thereby reducing the reaction to convert CO back to CO2.Inductively-coupled hybrid plasma catalysis allows access to study and to utilize high CO2 conversion in a non-thermal plasma regime.This advance offers opportunities to investigate the possibility to use radio frequency inductively-coupled plasma to store superfluous renewable electricity into high-valuable CO in time where the price of renewable electricity is plunging.

Tunable engineering of photo-and electro-induced carrier dynamics in perovskite photoelectronic devices

The last decade has witnessed great progress in photovoltaic technology based on organometal halide perovskites because of their low nonradiative recombination loss,long carrier lifetime,and long diffusion length.The excellent optical properties and easy preparation of organometal halide perovskite-based photovoltaic products enable their wide applications in electro-optical and opto-electrical conversions.In this review,photoinduced free carriers,exciton recombination,and diffusion properties of perovskite photoelectronic devices are discussed.By controlling grain sizes and grain boundaries,suppressing defects,and conducting interfacial charge transfer,their dynamics can be controlled in a versatile manner.The generality and differences in"effective carriers"for device applications,including their electro-optical and opto-electrical conversions,are discussed.In all-optical devices,a strong light-matter interaction causes nonlinear effects,such as two-photon absorption,self-phase modulation,and optical blenching,which enable high-resolution imaging,optical modulation,and optical switching.This review provides a basis for constructing high-performance photoelectronic devices.