| 摘要: | 基於釕的電極用於超級電容器，其具有高比電容（Cp）和導電性以及其他贗電容材料。應用熱分解（TD）作為質量電極製造方法是可靠的。然而，由於在處理期間形成的不同晶體結構，控制退火溫度仍然存在挑戰。含水結構對應於較低結晶特性，其由較低退火溫度處理產生，與由較高熱處理產生的結晶 - 無水結構相比，證明其具有高1000倍的Cp。具有多次退火（MA）處理的改性TD能夠保持含水形式，具有高穩定性和耐久性性能。首先，為了確定最佳退火溫度，Ru基電極的單一退火（SA）在不同的熱條件下進行：225℃，250℃和275℃，退火持續時間為3小時。其次，在總共3,4.5和6小時的不同退火持續時間內引入作為改性TD的MA。不同的MA時間：在這些不同的持續時間中應用2倍MA和3倍MA。與SA不同，在MA處理中，總Ru沉積基底沒有直接完全掉落。它分為2和3等體積分別為2次和3次MA。通過XRD，XPS和SEM表徵沉積物形態和結構。此外，通過循環伏安法測試分析了沉積物的電化學性能。第三，選擇最好的MA處理產生的沉積物，加入不同量的2.5wt％，5wt％，10wt％和20wt％的剝離石墨烯。然後基於沉積物表現出的電化學性能確定最佳添加量。
本研究中TD的最佳退火溫度為250oC。該確定基於第一SA的沉積物的電化學性能。沉積物在5mV / s下的Cp值為163.4F / g，在500mV / s時為76.0F / g，保留率為46.5，穩定性為74％。另一方面，總退火持續時間為6小時的3倍MA能夠在5mV / s和500mV / s的掃描速率下提供更好的性能，Cp值為308.8F / g和190.6F / g。保留率約為61.7，穩定性為93％。 EC石墨烯的添加旨在由於其較低的吸濕性而保持良好的沉積耐久性。添加到基於Ru的沉積中的最佳EC石墨烯量為5％，具有更好的電化學性能。 EC石墨烯摻雜沉積物的Cp值較高，mV / s時為407.1 F / g，500mV / s時為240.8 F / g，穩定性為96％。
經證實，多次退火處理的性能幾乎是單次退火處理的3倍。該處理能夠在這種熱條件下保持含水形式的RuO2導致更高的Cp值。此外，MA通過更短的保持時間提供更好的熱量通過每層。因此，它可以防止在表面形成高度有序的金紅石。此外，為了提高MA生成的沉積物的耐久性和穩定性，添加EC石墨烯作為摻雜劑。事實證明，EC石墨烯由於其較少的吸濕性能而能夠提高性能。
;Ruthenium-based electrodes are used for supercapacitor with its high specific capacitance (Cp) and conductivity among other pseudocapacitive materials. Applying Thermal Decomposition (TD) as mass electrode fabrication method is reliably proven. However, challenges are remains in controlling annealing temperature due to different crystal structure formed during the treatment. Hydrous structure corresponds to the less crystalline characteristic which is resulted from lower annealing temperature treatment proven to have 1000 times higher Cp compared to crystalline-anhydrous structure resulted from higher thermal treatment. Modified TD with multiple-annealing (MA) treatment is able to maintain hydrous form with high stability and durability performance.
First, to determine the optimum annealing temperature, single annealing (SA) of Ru-based electrode is done in different thermal conditions: 225oC, 250oC, and 275oC with annealing duration of 3 hours. Second, MA as modified TD is introduced in different annealing duration of total 3, 4.5, and 6 hours. Different MA times: 2-times MA and 3-times MA applied in these various durations. Different with SA, in MA treatment, total Ru deposition base is not fully dropped directly. It is divided into 2 and 3 equal volume for 2 times and 3 times MA, respectively. Deposit morphology and structure are characterized by XRD, XPS, and SEM. Furthermore, electrochemical performance of deposit is analyzed by Cyclic Voltammetry test. Third, the best MA treatment produced deposit was chosen to be added with exfoliated graphene at various amount of 2.5wt%, 5wt%, 10wt%, and 20wt%. Optimum addition amount then determined based on the electrochemical performance exhibited by deposit.
Optimum annealing temperature for TD in this research is 250oC. This determination is based on the electrochemical performance of deposit by first SA. Deposit exhibit Cp value 163.4 F/g at 5 mV/s and 76.0 F/g at 500 mV/s with retention reach 46.5 and stability of 74%. On the other hand, 3-times MA in total annealing duration of 6 hours able to give better performance with Cp value of 308.8 F/g and 190.6 F/g at scan rate of 5mV/s and 500 mV/s, respectively. The retention is about 61.7 with the stability of 93%. Addition of EC graphene was aimed to maintain good durability of deposit due to its less hygroscopic behavior. The optimum EC graphene amount to be added into Ru based deposition was 5% with better electrochemical performance. The Cp value of EC graphene doped deposit was higher, about 407.1 F/g at mV/s and 240.8 F/g at 500mV/s with the stability of 96%.
Multiple-annealing treatment had proven give almost 3 times better performance than single annealing treatment. This treatment was able to maintain RuO2 in hydrous form in such thermal condition resulted in higher Cp value. Moreover, MA provide better heat spread through each layer by shorter holding time. Thus, it prevents high ordered of rutile formation at the surface. Furthermore, to enhance the durability and stability of MA produced deposit, EC graphene was added as doping agent. It’s proven that EC graphene able to enhance the performance due to its less hygroscopic behavior. |
