Development of RuS_(2) for near-infrared photodetector by atomic layer deposition and post-sulfurization

The chalcogenides of platinum-group metals(PGMs)have been known to be present in minerals and the intermediate products of refining.Over recent years,their applications in various fields,including catalysis,have been explored.Given that certain PGM chalcogenides behave as compound semiconductors,they can be used as materials for photodetectors.In this study,RuS_(2),featuring a bandgap suitable for near-infrared photodetectors,was prepared by forming Ru on a SiO_(2)/Si substrate via the atomic layer deposition method using[Ru(TMM)(CO)_(3)]as the precursor.Annealing was conducted at 800℃ for 1 h under H_(2)S flow.High-resolution transmission electron microscopy(HRTEM)and X-ray diffraction(XRD)analysis clearly confirmed that the as-deposited hexagonal close-packed(hcp)Ru transformed to cubic RuS_(2) after post-annealing.The surface morphologies,chemical states,and electrical and optical properties of RuS_(2) were investigated.The influence of the metallic Ru surface morphology prior to sulfurization on the reaction between Ru and H_(2)S was also discussed.To evaluate the potential of using RuS_(2) as a photodetector,a photodetector was fabricated by forming electrodes on RuS_(2) to measure its photocurrent under near-infrared light.Thus,RuS_(2) was proven to exhibit a short response time(59μs)and generate a photocurrent of 84 nA under near-infrared light at 940 nm.

Engineering heterostructure and crystallinity of Ru/RuS_(2) nanoparticle composited with N-doped graphene as electrocatalysts for alkaline hydrogen evolution

Crystalline engineering and heterostructure have attracted much attention as effective strategies to improve the electrocatalytic activity for hydrogen evolution reaction(HER).In this study,a new heterostructure catalyst(Ru/RuS_(2)@N-rGO)with low crystallinity was fabricated by a simple and low-temperature method for HER in alkaline solution,applying the Na_(2)SO_(4)as S source and polypyrrole as N source.Optimizing through the controllable crystalline engineering and composition ratio of Ru and RuS_(2),the Ru/RuS_(2)@N-rGO heterocatalyst at the calcining 500°C revealed highly efficient HER activity with overpotential 18 mV at a current density 10 mA/cm^(2)and remarkable stability for 24 h in 1.0 mol/L KOH.This work provides a facile and effective method in designing advanced electrocatalysts for HER in the alkaline electrolytes by synergistically structural and component modulations.