通过简单的一锅法制备Fe2O3、 Fe3N、单原子Fe(SA-Fe)和N掺杂的磁性石墨烯材料(Fe-MNG)应用于催化活化过一硫酸盐(PMS).结果 表明,Fe-MNG/PMS体系可在宽的pH范围(3-10)氧化降解磺胺异恶唑(SIZ),降解率均达到99％以上.经过五次循环使用其对SIZ的降解率仍保持在95％以上.Fe-MNG中的SA-Fe、N等活性位点可高效催化活化PMS产生各种活性氧物种(ROS).淬灭实验和电子顺磁共振波谱分析表明Fe-MNG/PMS体系中产生多种ROS,包括硫酸根自由基(SO4·-)、羟基自由基(HO·)和单线态氧(1O2),证明存在自由基和非自由基两种氧化过程.此外,Fe-MNG具有大的比表面积(446.18m2/g),能将水中有机微污染物吸附富集到材料表面,同时在Fe-MNG表面催化PMS产生大量ROS,实现对有机微污染物的原位、高效氧化去除.Fe-MNG还具有磁性,易于分离和回收,具有潜在的应用前景.

Single-atom Cu catalytic sites supported on reduced graphene oxide exhibited an enhanced performance toward the activation of peroxymonosulfate.

The development of low-cost, highly efficient and durable non-precious-metal (NPM) electrocatalysts for the oxygen reduction reaction (ORR) is of great significance. Herein, we report an ingenious two-step strategy for the fabrication of NPM electrocatalysts containing multifarious cobalt species embedded in nitrogen-rich nanocarbons (Co-N-C). Firstly, Co ions were fixed by coordination with 1H-Imidazo[4,5-f][1,10]phenanthroline (Hip), and secondly the Co-Hip precursor with abundant Co, C and N sources was subjected to calcination at various temperatures (700-900 °C). The obtained Co-N-C catalysts exhibited excellent activity in terms of the ORR in alkaline conditions, with a half-wave potential of 0.82 eV versus the reversible hydrogen electrode, which is close to that of commercial Pt/C. Moreover, the Co-N-C exhibited an unexpected catalytic activity with long-term stability and immunity to methanol which is better than commercial Pt/C catalyst, suggesting that Co-N-C with dual active sites of the single-atom Co sites (Co-N4) and Co2N can be a promising alternative to replace Pt-based electrocatalysts in fuel cells. This work can provide a new route to designing promising catalysts with dual active sites for ORR.

Firstly, titanium dioxide nanoparticles ( TiO2 NPs) was modified to the surface of indium tin oxide ( ITO) electrode by high-temperature calcination to prepare TiO2 NPs/ITO electrode. And then sulfide quantum dots( PbS QDs) were modified to the surface of TiO2 NPs/ITO electrode by successive ionic layer adsorption and reaction( SILAR) cycle to prepare the PbS QDs/Ti02 NPs/ITO electrode. And it was used to detect glutathione( GSH). In this sensor, when PbS QDs are excited by 470 nm visible light, it will produce electrons ( e) and holes (11+). Immediately after, h+ will be captured by GSH in solution, and then GSH is oxidized into GSSH. Therefore, the recombination of electrons and holes were avoided effectively. Thus the photoelectric efficiency has been significantly improved. This sensor had satisfactory sensitivity and selectivity for GSH. what' s more, the detection range is 0. 06-1 mmol/L, and the detection limit ( LOD) is 4. 6 x 10-3 mmol/L( S/N= 3)