【摘要】：電極材料是決定電容性能的重要因素。貴金屬氧化物IrO2通過自身的氧化還原反應(yīng)來實現(xiàn)能量的存儲,理論上有著很高的贗電容,同時又具金屬導(dǎo)電特性和優(yōu)異的耐酸堿腐蝕性,是優(yōu)秀的電容儲能材料。目前對IrO2作為電容器電極材料的報道相對較少。添加CeO2可有效提高氧化釕電容性能,但是未見有關(guān)CeO2對IrO2基氧化物電容性能影響的研究報導(dǎo)。本文采用熱分解法制備了銥鈰二元和銥錫鈰三元電極材料。采用XRD、SEM測試手段表征了電極材料的相結(jié)構(gòu)及微觀形貌,并采用循環(huán)伏安和恒流充放電、交流阻抗等方法對其電化學(xué)性能進行了詳細研究。結(jié)果如下：(1)制備溫度對Ti/Ir0.7Ce0.3O2電極結(jié)構(gòu)和電容性能有顯著影響。隨制備溫度升高，，Ir0.7Ce0.3O2涂層由非晶態(tài)向晶態(tài)轉(zhuǎn)變,晶化程度逐漸升高,電極比電容則呈現(xiàn)先增大后減小變化。當制備溫度為380℃時,Ti/Ir0.7Ce0.3O2電極的電容達到最大值。經(jīng)過8000次循環(huán)充放電測試后,比電容增加6.8%,說明該電極擁有優(yōu)異的循環(huán)充放電穩(wěn)定性。(2)成分對Ti/IrO2-CeO2電極的結(jié)構(gòu)與電容性能亦有顯著影響。隨CeO2含量增加,IrO2晶化程度逐漸降低,說明CeO2有抑制IrO2結(jié)晶的作用。添加60mo1%CeO2可獲得最高比電容,但功率特性較差。添加40% CeO2也能明顯提高Ti/IrO2-CeO2電極的比電容,此時功率特性明顯得到改善。CeO2含量升高會導(dǎo)致電極涂層導(dǎo)電性能下降,當CeO2添加量達到80%時,整個電極相當于一個電阻。(3)CeO2替代Tr0.3Sn0.7O2中部分SnO2可有效提高電極電容性能。隨CeO2含量增加,IrO2-SnO2晶化程度逐漸下降,當CeO2含量超過30mol%時,IrO2-SnO2為非晶結(jié)構(gòu)。含10mol%CeO2電極的比電容為392.3 F/g,20mol%CeO2電極的比電容可達505.7F/g,均高于Ti/Ir0.3Sn0.7O2電極,后者提高約2倍。CeO2在0～20mol之間,電極具有較好的功率特性。繼續(xù)添加CeO2,功率特性衰減嚴重,與電極導(dǎo)電性下降有關(guān)。(4)Ti/Ir0.3Sn0.5Ce0.2O2電極在340和380℃可獲得較高比電容。嘗試采用交流阻抗方法對電極電容性能進行表征,比電容分別522 F/g,490 F/g,高于循環(huán)伏安方法計算得到的電容,因為交流阻抗可減少溶液電阻對電容的影響。同時對交流阻抗數(shù)據(jù)進行擬合,得到電極的內(nèi)外活性比例,為電極內(nèi)外活性面積的分析提供了新方法。
[Abstract]:The electrode material is an important factor to determine the performance of the capacitor. The noble metal oxide IrO2 can realize the storage of energy by the self-oxidation reduction reaction, has a high pseudo-capacitance in theory, and also has the characteristics of metal conduction and excellent acid and alkali resistance, and is an excellent capacitive energy storage material. The current coverage of IrO2 as a capacitor electrode material is relatively small. The addition of CeO2 can effectively improve the performance of the oxidation and capacitance, but no research has been found on the effect of CeO2 on the capacitance performance of the IrO2-based oxide. In this paper, the three-way electrode materials of the binary and the tribdenum disulfide are prepared by the thermal decomposition method. The phase structure and micro-morphology of the electrode material were characterized by XRD and SEM. The electrochemical performance of the electrode material was studied by cyclic voltammetry and constant current charging and discharging, and AC impedance. The results are as follows: (1) The preparation temperature has a significant effect on the structure and the capacitance of the Ti/ Ir0.7Ce0. 3O2 electrode. As the preparation temperature is increased, Ir0.7Ce0. 3O2 coating is changed from the amorphous state to the crystalline state, the degree of crystallization is gradually increased, and the ratio of the electrode to the capacitance is firstly increased and then the change is reduced. The capacitance of Ti/ Ir0.7Ce0. 3O2 electrode reached the maximum when the preparation temperature was 380 鈩

本文編號：2464160