Study On Like Fenton-photocatalytic Wastewater Fuel Cell System

Wastewater contains a large number of organic pollutants,and organic matter contains rich chemical energy.Therefore,developing a new approach to eliminate organic wastes and simultaneously recover the ample chemical energy stored in them would be greatly promising.The photocatalytic fuel cell?PFC?as a novel technology for organic pollutants degradation and simultaneous electricity production has drawn increasing attention.However,the performance of the existing PFC systems is still limited because the main radical reactions for organic pollutants degradation of these established PFCs principally occur on the surface of electrodes material,which resulted in a lower reaction efficiency.On this basis,we proposed here a new like Fenton-photocatalytic fuel cell?Fenton-PFC?system by introduce ferrous ions to the existing PFC system which can extend the radical reactions from occurring on the he surface of electrodes material to the whole system,so the radical reactions can be strengthened to enhance the performance of refractory organic pollutants degradation and electricity production simultaneously.Preparation of anode and cathode electrodes.In this paper,first,the TiO₂ nanotube array?TNA?photoanode was prepared and its lattice structure of the nanostructure array was detected by scanning electron microscopy?SEM?and X-ray diffraction?XRD?.At the same time,Pt decorated Si photovoltaic cell?Pt/SiPVC?was obtained by decorating Pt black on the Ag grids of Si photovoltaic cell?SiPVC?that has a high visible light response efficiency for its special p-n type structure.TNA photoanode has a neat uniform structure and its photocurrent density can reach 0.53 mA cm^-22 and 0.73 mA cm^-22 and didn't decrease significantly under UV light?0.0 V vs.Ag/AgCl reference electrode?and solar light?0.6V vs.Ag/AgCl reference electrode?;the photocurrent density of Pt/SiPVC photocathode can also reach 0.42 mA cm^-22 and was relatively stable under solar light?-0.2 V vs.Ag/AgCl reference electrode?.Therefore,both of them have good photoelectric response and stability.The design of like Fenton-photocatalytic fuel cell?Fenton-PFC??TNA-Pt?system.The like Fenton-PFC?TNA-Pt?system was established with TNA as the anode material,Pt black as the cathode material,FeSO₄ as the Fe²⁺source,Na₂SO₄ as the electrolyte and methyl orange?MO?as the substrate under the UV irradiation of 1.0 mW cm^-22 light intensity.The paper studied the effect of electrolyte concentration,pH and Fe²⁺concentration on the like Fenton-PFC system.The results showed that the performance of the like Fenton-PFC?TNA-Pt?system was optimized at0.10 M Na₂SO₄,pH 1.5 and 0.2 mM Fe²⁺:the short-circuit current density(J_sc)reached 1.57 mA cm^-2,the maximum output power density(JV_max)reached 0.57 mW cm^-22 and the degradation rate of MO was 97.34%after60 min.In order to evaluate the performance of the PFC system,methyl orange,methylene blue and Congo red and tracycline as typical refractory organics were selected as model substrates to examine the enhanced performance in electricity generation and organic degradation via the like Fenton-PFC?TNA-Pt?system compared with the traditional PFC?TNA-Pt?system under the same conditions.The results showed that the degradation rates of the like Fenton-PFC?TNA-Pt?system were 97.34%,95.36%,93.23%and 73.80%,which were 62.35%,51.61%,52.65%and 39.40%higher than the traditional PFC?TNA-Pt?.Meanwhile,the electricity generation of the like Fenton-PFC is up to 1.2–2.04 times larger than the traditional PFC.The results show that the like Fenton-PFC system can effectively improve the performance of the traditional PFC.The design of a solar responsive dual photoelectrodes like Fenton-PFC?TNA-Pt/SiPVC?system.In order to further improve the solar response efficiency of the like Fenton-PFC system,the Pt/SiPVC that have high visible light responding performance was used as the photocathode material with TNA as the photocathode,FeSO4 as the Fe²⁺source,0.10 M Na₂SO₄ as electrolyte and methylene blue?MB?as substrate to established a solar responsive dual photoelectrodes like Fenton-PFC?TNA-Pt/SiPVC?system under the simulated solar light of 100 mW cm^-22 light intensity.The results showed that the performance of the like Fenton-PFC?TNA-Pt/SiPVC?system was optimized at pH 3.0 and 0.2 mM Fe²⁺:the J_scc was 0.322 mA cm^-2,JVmax was 0.103 mW cm^-22 and the degradation rate of MB was 91.98%after 90 min.And under the same conditions,the degradation rates of like Fenton-PFC?TNA-Pt/SiPVC?system for methyl orange,methylene blue and Congo red and tracycline were respectively91.98%,98.57%,92.36%and 68.09%,which are 29.63%,46.96%,39.71%and 28.69%higher than the traditional PFC?TNA-Pt/SiPVC?system.Meanwhile,the electricity generation of the Fenton-PFC is up to1.41-1.60 times larger than the traditional PFC.