Water-soluble, highly emissive, color-tunable, and stable Cu:ZnSeS/ZnS core/shell doped nanocrystals (d-dots) with pure dopant emission have been synthesized through a simple aqueous synthetic route. The influence of various experimental variables, including introduction of chloride ions, amount of mercaptopropanoic acid (MPA), pH value and Cu-doping concentration, on the optical properties of Cu dopant emission have been systematically investigated. Through epitaxial growth of a ZnS shell on Cu:ZnSeS cores, the fabricated Cu:ZnSeS/ZnS d-dots exhibit a high PL QY of up to 40%, which is the highest ever reported for any type of water-soluble Cu-doped selenide-based II–VI semiconductor nanocrystals (NCs). Moreover, the serious photostability problem of Cu-based d-dots in the presence of air and light is solved and the quenching of the excitonic emission is suppressed as well. The stable testing of these highly luminescent d-dots shows that the Cu:ZnSeS/ZnS d-dots have better photostability and preserve more than ~90% of the initial intensity in the presence of air and light 30 days later. This new class of green emissive material shows their potential applications in biolabeling, bioimaging, and light emitting devices.

Photodegradation of gas phase benzene by SnO₂ nanoparticles has been studied in humid air, dry air and N₂ by using a tubular photoreactor. The SnO₂ nanoparticles are synthesized by the oxidation of anhydrous stannic chloride (SnCl₄) in a propane/air turbulent flame. Direct hole oxidation and the ·OH radical mechanisms have been discussed based on experimental results. The goal of this research is to explore a viable and efficient alternative photocatalyst and photocatalytic process, in particular, for humidity-tolerant photocatalyst or photocatalytic process in environmental applications.

This study explored the regenerated performance of activated carbon (AC) as SO₂ adsorbent. The optimal conditions of SO₂ removal were determined by experiment, and then the adsorption efficiency of AC was studied by a method of thermal regeneration. The characteristics of regenerated AC were analyzed by Brunauer-Emmett-Teller (BET) and Scanning Electron Microscopy (SEM) methods. The test results showed that the most suitable adsorption conditions were using 4 g of activated carbon, 1.65 L/min gas flue rate, and 5% O₂. During the ten regenerations, the desulfurization efficiency and sulfur capacity of AC still maintained a high level. The characterization results showed that the increase of material surface area and pore volume were 101 m² g⁻¹, and 0.13 cm³ g⁻¹, respectively, after the cycles.