CrI3-WTe2: A Novel Two-Dimensional Heterostructure as Multisensor for BrF3 and COCL2 Toxic Gases

2D Heterostructure of CoCl2 /Co3 O4 Built for Strong Enhanced Magnetism

As a remarkable structure, 2D magnetic heterojunctions have attracted researchers' attention owing to their controlled manipulation in the electronic device. However, successful fabrication as well as modulation of their structure and compound remain challenging. Herein, a novel method is designed to obtain a CoCl2 /Co3 O4 heterojunction on Si/SiO2 substrate with the assistance of supercritical CO2 (SC CO2 ), and the as-fabricated sample has significantly increased coercivity and saturation magnetization, which is 11 times higher than pure Co3 O4 . Further, it can be found that the CO2 pressure has the decisive effect on the saturation magnetization of the sample. Therefore, it suggests that the tunable electronic-magnetic device can be anticipated to be obtained in the future.

Metal-Decorated Phthalocyanine Monolayer as a Potential Gas Sensing Material for Phosgene: A First-Principles Study

Research into a gas sensing material with excellent performance to detect or remove toxic phosgene (COCl₂) is of great significance to environmental and biological protection. In the present work, the adsorption performance of COCl₂ on pristine phthalocyanine (Pc) and metal-decorated Pc (MePc, Me = Cu, Ga, and Ru) monolayers was studied by first-principles calculations. The results show that the absorption process of COCl₂ on pristine Pc and CuPc both belong to physisorption, indicating that they are not suitable gas sensing materials for COCl₂. When Pc sheets are decorated by Ga and Ru atoms, the adsorption of COCl₂ is changed into chemisorption, and the corresponding adsorption energies are -0.57 and -0.50 eV for GaPc and RuPc, respectively. The microcosmic mechanism between COCl₂ and adsorbents (GaPc, RuPc) was clarified by the analysis of the density of states, the charge density difference, and the Hirshfeld charge. In addition, the COCl₂ adsorption results in a significant conductivity variation of the RuPc monolayer, demonstrating it exhibits a high sensitivity to the COCl₂ molecule. Meanwhile, quick desorption processes were noticed at various temperatures for the COCl₂/RuPc system. Consequently, the RuPc monolayer can be considered as a potential candidate for phosgene sensors because of the moderate adsorption strength, high sensitivity, and fast desorption speed.