A Green Strategy to Synthesize Ag/Ag3PO4/Chitosan Composite Photocatalysts and Their Photocatalytic Degradation Performance under Visible Light Irradiation

In this work, the plasmonic Ag/Ag3PO4/chitosan(Ag/Ag3PO4/CS) composite photocatalyst was prepared by a low-temperature strategy. Environmentally friendly CS plays triple vital roles in this composite. First, it was devoted to in situ reducing metallic silver from silver ions of Ag3PO4. Also, as the carrier of Ag/Ag3PO4 nanoparticles,CS can effectively prevent aggregation. Furthermore, benefitting from the settlement of hydrophilic CS, the prepared composite could be easily separated and recovered from the solution system. X-ray diffraction(XRD), the scanning electron microscope, energy-dispersive X-ray spectroscopy(EDS), ultraviolet-visible(UV-vis) diffused reflectance spectroscopy, and X-ray photoelectron spectroscopy(XPS) were employed to characterize the properties of materials. The results of photo-decomposition testing showed that the Ag/Ag3PO4/CS composite possessed good activity for the decomposition of Rhodamine B(Rh B) under visible light.

Breather Interaction Properties Induced by Self-Steepening and Space-Time Correction

We study the properties of breather interactions in nonlinear Kerr media with self-steepening and space-time correction and with either self-focusing or self-defocusing nonlinearity,and present a new family of exact breather solutions via the Darboux transformation with a special-designed quadratic spectral parameter.In contrast to the previous results of the nonlinear Schrodinger equation(NLSE)hierarchy,we show that the relative phase of colliding breathers has a significant effect on the collision manifestation.In particular,only the out-of-phase interactions can generate small amplitude waves at the collision center,which are analogous to the NLSE superregular breathers.Our results will deepen our understanding of the properties of breather interactions and they will offer the possibility of experimental observations of super-regular breather dynamics in systems with self-steepening and space-time correction.

Tungsten chalcogenides as anodes for potassium-ion batteries

Potassium-ion batteries(PIBs)by virtue of their strong cost competitiveness and similar electrochemical properties to lithiumion batteries have been deemed to be a promising electrochemical energy storage technology.To promote the application in the commercial market,developing electrode materials with high specifi c capacities,superior cycling stability,and reliable safety is of great importance.Anode materials as an important component of PIBs play a decisive role,among which twodimensional transition metal chalcogenides(2D TMCs)have attracted wide attention owing to their unique material and electrochemical properties.In the 2D TMCs’family,molybdenum chalcogenides as fl agship are the most studied materials and demonstrated the potential as anodes.With the deepening of research on 2D TMCs,another shining member that possesses similar properties to molybdenum chalcogenides,tungsten chalcogenides(WS_(2),WSe_(2),and WTe_(2)),has aroused tremendous attention.Despite many inspiring results,various challenges remain to be further addressed;meanwhile,some results are still unclear and disputed.Herein,this review fi rst introduces their material properties and electrochemical storage mechanisms.Then,we systematically overview the research progress and put forward promoting improvement strategies.Finally,challenges and opportunities that would be future research directions are discussed.

On the Security of Smart Home Systems:A Survey

Among the plethora of IoT(Internet of Things)applications,the smart home is one of the fastest-growing.However,the rapid development of the smart home has also made smart home systems a target for attackers.Recently,researchers have made many efforts to investigate and enhance the security of smart home systems.Toward a more secure smart home ecosystem,we present a detailed literature review on the security of smart home systems.Specifically,we categorize smart home systems’security issues into the platform,device,and communication issues.After exploring the research and specific issues in each of these security areas,we summarize the root causes of the security flaws in today's smart home systems,which include the heterogeneity of internal components of the systems,vendors'customization,the lack of clear responsibility boundaries and the absence of standard security standards.Finally,to better understand the security of smart home systems and potentially provide better protection for smart home systems,we propose research directions,including automated vulnerability mining,vigorous security checking,and data-driven security analysis.