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[Display omitted] • A green, high-efficiency, and recyclable eutectic solvent was designed for the recycling of EOL PV modules. • Eutectic solvent was used to separate the EVA and Al layers in end-of-life photovoltaic modules. • EVA was separated by hydrothermal method and the separation mechanism was revealed. • The EVA separation rate remains 100% after 10 solvent cycles. Sustainable End-of-life (EOL) photovoltaic (PV) modules recycling is essential for achieving resource conservation and alleviating environmental issues. Ethylene vinyle acetate (EVA) adhesive films separation is a prerequisite for the realization of valuable component recovery of PV modules. However, the conventional wet chemical separation processes are usually accompanied by the challenges of low separation efficiency, high toxicity and difficult multiple recycling. Herein, a green, biodegradable, low-cost and recyclable deep eutectic solvent (DES) is firstly developed to efficiently separate EVA films in EOL PV modules. The high temperature stability and the acidic characteristic of DES can facilitate the separation of EVA film between component layers. At 175 ℃, the warping effect caused by the differential thermal contraction between the module component layers creates favorable conditions for the efficient reaction and separation by the DES. Additionally, the acidic medium reacts with the aluminum electrode layer of PV cells, which further enhances the separation efficiency of EVA films. The EVA separation rate reached 100%, the separation rate of the EVA containing aluminum (Al) up to 98.4% after 12.5 h at 175 ℃. Moreover, the developed DES exhibits excellent recyclable performance, the EVA separation rate remained 100% after 10 cycles. Compared to the traditional solvent toluene, DES has advantages in terms of economics, environmental impact, and efficiency. This strategy of design a green, biodegradable, low-cost and recyclable solvent to replace traditional solvents, and provides a promising route to efficiently separate EVA films in EOL PV modules. [ABSTRACT FROM AUTHOR]

In this work, the effects of different copper salts on the etching behavior of n-type monocrystalline silicon wafers were detailedly studied. Firstly, the inverted pyramid, inverted pyramid-like and oval pit texturing structures were obtained by HF/H2O2/Cu(NO3)2, HF/H2O2/CuSO4 and HF/H2O2/CuCl2 etching systems. Then, the evolution process of copper nano-particles (Cu-NPs) deposition was studied to reveal the influencing mechanism of different anion species during the copper-assisted chemical etching (Cu-ACE) process. The textured wafer surfaces were characterized by scanning electron microscopy (SEM) and ultraviolet-visible (UVis) spectrophotometer, the etching rate, silicon wafer thinning and the deposition amount of Cu-NPs were systematically analyzed. The binding force between anion and cation species, the oxidation of anions and the formation of complex groups [CuCl2]− can greatly affect the deposition process of Cu-NPs, and resulting in different etching morphology and etching behavior. The moderate size and dispersive Cu-NPs in HF/H2O2/Cu(NO3)2 system leads to that the etching process is mild and the anisotropic etching ability can fully demonstrated. The regular inverted pyramid structures can be formed under low thinning of silicon wafers. [ABSTRACT FROM AUTHOR]

This paper proposes an adaptive dynamic programming (ADP)‐based decentralized event‐triggered control strategy for large‐scale nonlinear systems with event‐triggered scheme to efficiently reduce communication cost and computational burden. Under the event‐triggered mechanism, an local neural networks (NNs)‐based observer is introduced to identify the mismatched interconnections and the estimation error is guaranteed to be uniformly ultimately bounded (UUB). Then, a decentralized triggering condition related to the approximation error of interconnections is designed to reduce the local controller updates with guaranteed overall stabilization of large‐scale systems. By virtue of critic‐only structure, the local optimal control policy can be approximated via aperiodic tuning rule using ADP. In addition, the closed‐loop large‐scale system ensures to be asymptotically stable with adaptive triggering threshold according to Lyapunov method. Finally, the simulation results justify the theoretical analysis and illustrate the effectiveness of the proposed event‐triggered control (ETC) strategy. [ABSTRACT FROM AUTHOR]