Three-Dimensional Welded Mn_(1) Site Catalysts with nearly 100% Singlet Oxygen Fabrication for Contaminant Elimination

Reactive oxygen species(ROS)have a significant part in the elimination of recalcitrant organic pollutants and commonly coexist in one advanced oxidation system.It is difficult for us to make clear the effect of the co-instantaneous generation of radicals and nonradicals,which would cover and obscure the transformation pathway.Herein,a coordinate welding process is presented for fabricating accessible Mn1 site catalysts(Mn SSCs)in order to clarify the nonradical(singlet oxygen/^(1)O_(2))generated pathway and transformation in oxidative removal of contaminants.The Mn SSCs achieve nearly 100%^(1)O_(2) fabrication by activating peroxymonosulfate,which displays an excellent sulfamethoxazole elimination performance,super anti-anion interference,and extraordinary stability.As revealed by density functional theory calculations,the Mn SSCs with a special welded three-dimensional nanostructure could significantly boost the activation process by oxidizing the peroxymonosulfate at the interlayer of Mn SSCs and reducing dissolved oxygen on the surface of Mn SSCs.This design of Mn SSCs with a three-dimensional welded nanostructure might offer a potential approach for employing single site catalysts for environmental remediation.

Roles of glutathione and L-cysteine in the biomimetic green synthesis of CdSe quantum dots

Biological synthesis of quantum dots （QDs） as an environmental-friendly and facile preparation method has attracted increasing interests. However, it is difficult to distinguish the roles ofbio-thiols in QDs synthesis process because of the complex nature in organisms. In this work, the CdSe QDs synthesis conditions in organisms were reconstructed by using a simplified in vitro approach to uncover the roles of two small bio-thiols in the QDs formation. CdSe QDs were synthesized with glutathione （GSH） and L-cysteine （Cys） respectively. Compared with Cys at the same molar concentration, the CdSe QDs synthesized by GSH had a larger and broader particle size distribution with improved optical properties and crystal structure. Furthermore, quantum chemical calculations indicate that the stronger Cd^2＋ binding capacity ofGSH contributed a lot to the CdSe QDs formation despite ofthe greater capability Cys for selenite reduction. This work clearly demonstrates the different roles of small thiols in the Cd2^＋- stabilization in the environment and biomimetic QDs synthesis process.