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• The CuO/RuO 2 electrode was prepared by the two-step thermal decomposition method for the first time. • Compared with the ordinary RuO 2 electrode, the selectivity of CER of CuO/RuO 2 electrode is remarkably improved. • During the preparation of AEW, the HClO content of AEW2 (prepared by CuO/RuO 2) is 2.5 times that of AEW1 (prepared by RuO 2). • In the sterilization experiments on E. coli and B. subtilis , the germicidal efficacy of AEW2 is obviously superior to that of AEW1. Electrochemical chlorine evolution reaction (CER) is one of the most important practical applications of electrochemical reaction, which can be used for electrochemical disinfection. The electrochemical disinfectant of acidic electrolyzed water (AEW) is obtained by electrolyzing extremely dilute chlorine-containing solution in ion-exchange membrane electrolyzer. In the anode area, HClO is produced by CER, which has a strong bactericidal effect. Due to the low concentration of chloride ion, it is necessary to improve the CER selectivity of the electrode in order to improve the efficiency of chlorine electrolysis. In this paper, CuO/RuO 2 electrode was prepared by the two-step thermal decomposition method, and the surface morphology and electronic structure of RuO 2 electrode were modified. Compared with the ordinary RuO 2 electrode, the CER activity of CuO/RuO 2 electrode is improved. For the oxygen evolution reaction (OER), the activity of CuO/RuO 2 electrode is significantly lower than that of RuO 2 electrode. The CER mechanism of CuO/RuO 2 electrode is the second electron transfer, and the OER mechanism is the formation and transformation of OH ads. The potential difference between CER and OER of CuO/RuO 2 -3 electrode is 105 mV, which is 52 mV higher than that of RuO 2 electrode, so the selectivity of CER of CuO/RuO 2 electrode is remarkably improved. During the preparation of AEW, the HClO of AEW2 (prepared by CuO/RuO 2 -3 electrode) is 0.72 mmol/L, which is 2.5 times that of AEW1 (prepared by RuO 2 electrode). In the sterilization experiments on E. coli and B. subtilis , the germicidal efficacy of AEW2 (3.71 and 2.99 log 10 CFU/mL) is obviously superior to that of AEW1 (0.76 and 0.61 log 10 CFU/mL). [ABSTRACT FROM AUTHOR]

The research and development of high-efficiency low-temperature disinfection technology in all aspects of cold-chain food has begun to receive attention. This paper aims to develop low temperature acidic electrolyzed water (LT-AEW) disinfectant. The anti-freezing temperature, disinfection efficiency and practical application effect were evaluated in detail. The results had shown that the freezing point of AEW can be reduced to −18 °C by adding 25% CaCl 2 , 20% NaCl, 30% ethylene glycol (EG) and 35% propylene glycol (PG). At the low temperature (−1, −10 and −18 °C), the bactericidal efficiencies of all EG-acidic electrolyzed waters (EG-AEWs) with different EG contents were close. The reason is that although the low temperature environment will reduce the sterilization efficiency of EG-AEW, the addition of EG can promote the increase of HClO content in EG-AEW, thus increasing the sterilization efficiency. As long as the HClO content reached 35.2, 50.8 and 64.3 mg L−1, the killing logarithm (KL) value had achieved 4.50, 4.49 and 5.07 log 10 (CFU mL−1). Finally, the KL values of EG-AEW against Escherichia coli on the corrugated board and stainless-steel board both exceeded 3 log 10 (CFU mL−1) at the low temperature, which indicates that EG-AEW can be applied in food cold chain. • A low temperature acidic electrolyzed water (LT-AEW) is studied for the first time. • The freezing point of ethylene glycol AEW (EG-AEW) can reach to −18 °C. • The killing logarithm of EG-AEW against E. coli is 5.07 log 10 (CFU mL−1) at −18 °C. • EG-AEW can effectively sterilize E. coli on corrugated and stainless-steel board. [ABSTRACT FROM AUTHOR]