| With the increasing environmental damage,human life is facing different kinds of challenges,and the emergence of many new bacteria to human beings caused tremendous damage.Electrolyzed oxidizing water（EOW）as a new fungicide with sterilization completely,no residue,rapid,wide applicability,harmless,low cost,easy to use,less corrosive and so on,in recent years;it has shown excellent bactericidal effect in food,medical,health,and other crops.So prepared with a high concentration of available chlorine electrolysis of water has become the focus of our study.But when 0.05% sodium chloride solution was electrolyzed prepared by the electrolysis,generated at the anode with a germicidal effect ingredients available chlorine,oxygen evolution reaction will happen;so how to improve the chlorine evolution reaction,reducing the oxygen evolution reaction（OER）to increase chlorine evolutionreaction（CER）is also a focus of the study.Furthermore,since facing energy crisis,coupled with the cathode hydrogen evolution reaction will occur,it may prepared inverted pole electrode used to solve the energy problem is the content of this textbook study.In this paper,Ru-based group,the special morphology of Ru metal-metal oxides and catalytic activity compared with classical Adams method,the following key elements as follows:（1）By sol-gel method,we synthesie thread and leaf-like RuO2 catalyst,which were prepared to classic Adams method RuO2.By SEM can know,Adams catalyst has no special morphology and evere agglomeration.From chlorine evolution polarization curves,the chlorine evolution of thread and leaf-like are 77 mA·cm-2、57.6 mA·cm-2,which are higher than Adams 58 mA·cm-2.So,we have improved CER by enhancing the catalytic activity area.But on per unit of electricity,Adams method is 2.48 A·C-1 higher than the thread and leaf-like 1.16 A·C-1、0.73 A·C-1.Therefore,to achieve a real sense of high CER,we should not only consider the impact of morphology,but also the composition of the catalyst.（2）Solvothermal/hydrothermal method was used to prepare spherical and honeycomb catalyst.There is no agglomeration between particles and have a certain gap,especially spherical catalyst the gap is very large,and the surface is relatively smooth.XRD can be seen,the content of Ru is very large,because n-butanol/water has a certain reduction at high temperature and pressure,which will reduce Ru3+ to Ru.During the annealing process,only surface Ru can be oxidized to RuO2.By chlorine evolution polarization curves and Tafel curve analysis,we know spherical catalyst has the highest chlorine evolution current on per unit area and per unit of electricity,that are 90 mA·cm-2 and 10.45 A·C-1 which are 1.6 timse and 4.2 times than Adams;honeycomb chlorine evolution currents of 79 mA·cm-2 and 2.74 A·C-1 which are 1.4 timse and 1.1tims than Adams method.Chlorine evolution Tafel mechanism shows that desorption of chlorine is the rate control step,spherical catalyst has the highest CER since the gap is bigger.（3）Using solvothermal method to optimize the condition of spherical morphology.Seen from SEM the catalysts show good spherical morphology.XRD shows that the catalyst is a mixture of Ru and RuO2.From CV,we know that under different reaction temperature and time catalysts active area have much difference.The particle size of catalysts prepared at 120℃ is larger than 140℃ and 180℃.By comparation of CER,at 140℃ and 180℃ 2 h the reaction of chlorine evolution have a higher activity on per unit area were 89 mA·cm-2 and 90 mA·cm-2,respectively,on per unit of electricity are 10.07A·C-1 and 10.45 A·C-1,but Tafel slope shows that at 180℃ for 2 h is 38.8 mV.dec-1 less than 140℃ for 2h is 51.9 mV·dec-1,so 180℃ for 2 h is more conducive to chlorine desorption.（4）Solvothermal method was used to synthesis different proportions of Ru-Cu binary oxides.We can also obtain spherical dispersion,non-agglomerated composite oxide by adding different proportions of Cu O source.From XRD,we know that with increasing Cu content,the composite catalysts peak become more width and obvious,explaning crystals size is decreasing.That is to say adding CuO source can change the characteristics of Ru.With the increasing of Cu content,on per unit area and electricity,CER are showing increased initially and then decreased;as the ratio of Ru and Cu material was 1:0.8,the composite catalyst has the best activity for chlorine evolution at 11.6 A·C-1 higher than the pure Ru 10.45 A·C-1 on the unit of electricity.And the potential difference between oxygen evolution and chlorine evolution has the maximum reaching to 165 mV,whereas the pure Ru is 105 mV.So this ratio of Ru and Cu has improved the selective of CER. |
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