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[Display omitted] • An electrostatic dust removal method for solar photovoltaic panels is investigated. • The dust removal mechanism is analyzed. • Relative humidity affects the effectiveness of dust removal. • Optimizing the metal plate type can improve the dust removal efficiency. Electrostatic dust removal has the advantages of energy saving, high efficiency, and controllability, and has become the preferred dust removal solution for solar photovoltaic (PV) panels in recent years. This paper investigates a new electrostatic adsorption dust removal method for solar PV panels based on the electrostatic dust removal effect of carbon nanotubes (CNTs) transparent conductive films. In the sheet resistance range of 500–1×105 Ω/□, the electrostatic dust removal effect of CNTs transparent conductive films has little relationship with the film sheet resistance, and when the electric field strength in the dust removal area is 6 kV/cm, the final dust removal rate of different films can reach more than 98.6 %, and the power generation efficiency of the PV panels can reach 94–97 % of that of the ordinary PV panels in the surface clean state after dust removal. The influence of the environment on the dust removal effect is mainly reflected in the relative humidity. When the relative humidity of the dust removal environment is 70 %, it shows the optimal dust removal effect, and the electric field strength required for the dust particles to jump is the lowest, which is 2.46 kV/cm. The highest dust removal efficiency can be achieved by using a metal plate with a lower surface curvature of 1/9.08 cm−1, and the final dust removal rate can reach 98.92 %. The research results are of great significance for further developing electrostatic dust removal technology in the solar PV panel dust removal field. [ABSTRACT FROM AUTHOR]

Traditional thermosetting epoxy resins are widely applied in many fields due to their excellent performance. However, stable internal crosslinked networks hinder the repair of epoxy resins damaged during the operation and the recycling of decommissioned epoxy resins. Since vitrimers are epoxy resins that exhibit dynamic covalent bonding, reversible repair properties, and recyclability, they offer a potential solution to this problem. Therefore, by introducing an ester-exchange catalyst, we further introduced disulfide (S–S) bonds to the crosslinked network to construct a vitrimer resin exhibiting double-dynamic bonds, systematically investigated the basic thermodynamic and electrical properties of resins containing different S–S bond contents, and studied the self-healing properties of the possible multispecies and multiscale physical and electrical damages during device operation. Moreover, we investigated the self-healing properties of resins containing different S–S bonding contents. Results showed that the resin exhibited excellent electrical insulation, and the dynamic properties of the resin increased with the increasing number of S–S bonds in the crosslinked network, which considerably increased the repair efficiency and damage repair scale. In addition, the excellent dynamic properties rendered the resin degradable, enabling the non-destructive recycling of valuable materials from the resin matrix and specific processable remodelling and endowed the resin with thermally elastic shape memory properties. This work helps expand the class of vitrimer resins and promotes the application of vitrimers for manufacturing environmentally friendly electrical equipment. • Construction of a double dynamic cross-linked vitrimer resin system. • Comprehensive testing and analysis of the mechanical, thermal and electrical properties. • The prepared resins exhibit excellent overall performance as well as shape memory and degradability. • Carry out multi-type and multi-scale damage repair research of self-healing properties. • Can realize the non-destructive recovery of high-value materials from waste resin. [ABSTRACT FROM AUTHOR]

Composite cross-arms have been developed to take place of the steel cross-arm in the power system. In order to suit the environmental impact factors in the long-term operation, superior comprehensive properties of the internally insulated materials for composite cross-arm are required. In the present study, a syntactic foam based on hollow polymer microsphere (HPM)-filled siliconized epoxy resin (SER) was prepared for satisfying these requirements. First, the SER was synthesized using poly (methylphenylsiloxane) and an epoxy resin via a graft reaction. The as-synthesized SER was characterized via Fourier transform infrared, 1H nuclear magnetic resonance (NMR), and 13C NMR spectroscopies. Subsequently, a series of SER-based syntactic foams were fabricated using HPM with five different mass fractions. According to the thermogravimetric analysis results, the thermal stability of the composites considerably improved because of the introduction of the siloxane bond. The dielectric constant and dielectric loss of the composites simultaneously decreased with increasing HPM content. The dielectric strength of the composites remained 10.08–21.31 kV/mm after hydrothermal treatment, indicating excellent electrical insulation reliability. Notably, after water diffusion pre-stressing, the leakage current properties of the composites only slightly differed as the HPM content increased. These results further support their application as an internally insulated material for a composite cross-arm. Image 1 [ABSTRACT FROM AUTHOR]