Hydrophobic organic coating based water–solid TENG for water-flow energy collection and self-powered cathodic protection

Water-solid triboelectric nanogenerators(TENGs),as new energy collection devices,have attracted increasing attention in ocean energy harvesting and selfpowered sensing.Polyacrylic acid(PAA)coating,usually used on the surface of marine equipment,has the property of anti-aging and anti-wear but limits triboelectrical output when used with TENGs.In this paper,polyacrylic acid coating was modified with fluorinated polyacrylate resin(F-PAA)to increase its triboelectrical output,by 6 times,and also to increase its anti-corrosion property.In addition,the corrosion resistance property can be further enhanced by cathodic protection using the electrical output generated by the water-flow triboelectrical energy transfer process.Given their easy fabrication,water-flow energy harvesting,and corrosion resistance,PAA/F-PAA coating-based TENGs have promising applications in river and ocean energy collection and corrosion protection.

Broadband and wide-angle plane focal surface Luneburg lens

The energy crisis has aroused widespread concern, and the reform of energy structure is imminent. In the future,the energy structure will be dominated by the solar energy and other renewable energy sources. The solar concentrating technology as a promising method has been widely studied for collecting solar energy. However, the previous solar concentrating technologies suffer from some drawbacks, such as low focusing efficiency and large concentrating size. The Luneburg lens with highly efficient aberration-free focusing provides a new route for solar/energy concentrator. In this work, we designed a plane focal surface Luneburg lens(PFSLL) by transformation optics(TO). The PFSLL provides a relatively high focusing efficiency and concentration ratio of collection of energy. At the same time, it circumvents the disadvantage of curve surface of the classical Luneburg lens in device integration. Based on the reciprocity of electromagnetic waves, the PFSLL can also be applied to the antenna field to achieve broadband wide-angle scanning and highly directional radiation.

Coupling Enhancement of a Flexible BiFeO_(3) Film-Based Nanogenerator for Simultaneously Scavenging Light and Vibration Energies

Coupled nanogenerators have been a research hotspot due to their ability to harvest a variety of forms of energy such as light,mechanical and thermal energy and achieve a stable direct current output.Ferroelectric films are frequently investigated for photovoltaic applications due to their unique photovoltaic properties and bandgap-independent photovoltage,while the flexoelectric effect is an electromechanical property commonly found in solid dielectrics.Here,we effectively construct a new form of coupled nanogenerator based on a flexible BiFeO_(3) ferroelectric film that combines both flexoelectric and photovoltaic effects to successfully harvest both light and vibration energies.This device converts an alternating current into a direct current and achieves a 6.2% charge enhancement and a 19.3%energy enhancement to achieve a multi-dimensional"1+1>2"coupling enhancement in terms of current,charge and energy.This work proposes a new approach to the coupling of multiple energy harvesting mechanisms in ferroelectric nanogenerators and provides a new strategy to enhance the transduction efficiency of flexible functional devices.

Momentum-Dependent Symmetry Potential from Nuclear Collective Flows in Heavy Ion Collisions at Intermediate Energies

Within the isospin-dependent quantum molecular dynamics model, we investigate the nuclear collective flows produced in semi-central 197 Au＋197 Au collisions at intermediate energies. The neutron proton differential flows and difference of neutron proton collective flows are sensitive to the momentum-dependent symmetry potential. This sensitivity is less affected by both the isoscalar part of nuclear equation of state and in-medium nucleon- nucleon cross sections. Moreover, this sensitivity becomes pronounced with increasing the rapidity cut.

Hydrophobic MAO/FSG coating based TENG for self-healable energy harvesting and self-powered cathodic protection

An organic/inorganic hybrid coating with self-healable hydrophobicity is prepared as triboelectrical layer by micro-arc oxidation(MAO)and fluorinated sol-gel(FSG)coating.The MAO/FSG hybrid coating-based TENG(MF-TENG)has a current output of31μA and voltage output of 870 V,which is eight times that of the MAO based TENG.Compared with organic coating,the organic/inorganic hybrid coating has good wear resistance.When the fluorine composition on the surface of the coating is damaged,the self-healing hydrophobicity and electrical output are achieved by transferring loaded perfluorosilane to the damaged surface.The fluorinated sol-gel coating is hydrophobic,which ensures that the coating has good corrosion resistance.Also,the electricity generated in triboelectrification could improve the anti-corrosion performance by cathodic protection.Based on the anti-corrosion,anti-wear and self-healing properties,the MF-TENG has potential applicability in the field of energy collection,energy supply,and corrosion protection.