多孔銀的電催化性能研究
發(fā)布時(shí)間：2018-10-15 11:50
【摘要】：本文通過掃描電子顯微鏡、EDX能譜分析、電沉積技術(shù)等手段,循環(huán)伏安及恒電位等曲線的測(cè)定對(duì)多孔銀電極(NPS)及鉑微粒修飾多孔銀電極(NPS-Pt)對(duì)甲醛及葡萄糖溶液的電催化氧化性能展開了一系列研究。結(jié)果表明:當(dāng)多孔銀電極在0.3 mol/L的HCHO溶液中,支持電解質(zhì)KOH濃度為0.9 mol/L,掃描速度為20 mV/s時(shí)測(cè)得的甲醛的氧化峰電流密度最大且最穩(wěn)定。隨著循環(huán)次數(shù)的增加,多孔銀電極表面發(fā)生了一定程度的粗化甚至球化,比表面積減小,導(dǎo)致催化活性降低。葡萄糖在純銀電極上的氧化包括在0.7 V左右AgO出現(xiàn)時(shí)的直接氧化以及在負(fù)向掃描過程中伴隨著Ag2O出現(xiàn)時(shí)的逐漸氧化的過程。多孔銀電極對(duì)葡萄糖的催化活性明顯高于純銀電極。當(dāng)支持電解液KOH濃度為0.1 mol/L,葡萄糖濃度在10 mmol/L-30mmol/L范圍逐漸增大時(shí),多孔銀電極催化葡萄糖產(chǎn)生的氧化峰電流值也逐漸增大。隨著循環(huán)次數(shù)的增多,多孔銀電極催化葡萄糖的氧化峰電流密度逐漸減小,電極表面發(fā)生了粗化。在1 mmol/L H2PtCl6.6H2O+0.5 mol/L H2SO4溶液中對(duì)多孔銀電極進(jìn)行電沉積鉑時(shí),當(dāng)沉積速度為10 mV/s,沉積圈數(shù)為5圈時(shí),得到的鉑微粒修飾多孔銀電極對(duì)甲醛的催化氧化活性最高。整個(gè)電沉積過程及修飾電極對(duì)甲醛催化的動(dòng)力學(xué)過程均受擴(kuò)散控制。多孔銀電極沉積鉑后多孔的形貌并沒有改變,能譜顯示修飾電極鉑含量為3.12%,沉積鉑的總量約為100μg。對(duì)多孔銀電極及其修飾電極對(duì)甲醛的電催化氧化活性及穩(wěn)定性進(jìn)行比較,測(cè)試結(jié)果表明:甲醛在修飾電極上氧化活化能低、反應(yīng)速度快、活性高,穩(wěn)定性也得到了明顯的提高。
[Abstract]:In this paper, scanning electron microscopy, EDX energy spectrum analysis, electrodeposition technology and other means, Determination of cyclic voltammetry and potentiostatic curves the electrocatalytic oxidation properties of porous silver electrode (NPS) and platinum particle modified porous silver electrode (NPS-Pt) for formaldehyde and glucose solution were studied. The results show that the oxidation peak current density of formaldehyde is the largest and the most stable when the concentration of supporting electrolyte KOH is 0. 9 mol/L, and the scanning speed is 20 mV/s, when the porous silver electrode is in the HCHO solution of 0. 3 mol/L. With the increase of cycle times, the surface of porous silver electrode is coarsened or even spheroidized to a certain extent, and the specific surface area decreases, which leads to the decrease of catalytic activity. The oxidation of glucose on the sterling silver electrode includes the direct oxidation at about 0.7 V AgO and the gradual oxidation with the appearance of Ag2O in the negative scanning process. The catalytic activity of porous silver electrode for glucose was significantly higher than that of pure silver electrode. When the concentration of support electrolyte KOH was 0. 1 mol/L, glucose concentration increased in the range of 10 mmol/L-30mmol/L, the oxidation peak current value of glucose catalyzed by porous silver electrode increased gradually. With the increase of cycle times, the oxidation peak current density of glucose catalyzed by porous silver electrode decreases gradually and coarsening occurs on the electrode surface. When platinum was electrodeposited in 1 mmol/L H2PtCl6.6H2O 0.5 mol/L H2SO4 solution, the platinum particle modified porous silver electrode had the highest catalytic activity for formaldehyde oxidation when the deposition rate was 10 mV/s, and the number of cycles was 5 cycles. The whole electrodeposition process and the kinetic process of the modified electrode catalyzed by formaldehyde were controlled by diffusion. The morphology of the porous electrode was not changed after the deposition of platinum on the porous silver electrode. The platinum content of the modified electrode was 3.12 and the total amount of platinum deposited was about 100 渭 g. The electrocatalytic oxidation activity and stability of the porous silver electrode and its modified electrode for formaldehyde were compared. The results showed that the oxidation activation energy of formaldehyde on the modified electrode was low, the reaction rate was high, the activity was high, and the stability was improved obviously.
【學(xué)位授予單位】：大連交通大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TB383.4;O614.122
[Abstract]:In this paper, scanning electron microscopy, EDX energy spectrum analysis, electrodeposition technology and other means, Determination of cyclic voltammetry and potentiostatic curves the electrocatalytic oxidation properties of porous silver electrode (NPS) and platinum particle modified porous silver electrode (NPS-Pt) for formaldehyde and glucose solution were studied. The results show that the oxidation peak current density of formaldehyde is the largest and the most stable when the concentration of supporting electrolyte KOH is 0. 9 mol/L, and the scanning speed is 20 mV/s, when the porous silver electrode is in the HCHO solution of 0. 3 mol/L. With the increase of cycle times, the surface of porous silver electrode is coarsened or even spheroidized to a certain extent, and the specific surface area decreases, which leads to the decrease of catalytic activity. The oxidation of glucose on the sterling silver electrode includes the direct oxidation at about 0.7 V AgO and the gradual oxidation with the appearance of Ag2O in the negative scanning process. The catalytic activity of porous silver electrode for glucose was significantly higher than that of pure silver electrode. When the concentration of support electrolyte KOH was 0. 1 mol/L, glucose concentration increased in the range of 10 mmol/L-30mmol/L, the oxidation peak current value of glucose catalyzed by porous silver electrode increased gradually. With the increase of cycle times, the oxidation peak current density of glucose catalyzed by porous silver electrode decreases gradually and coarsening occurs on the electrode surface. When platinum was electrodeposited in 1 mmol/L H2PtCl6.6H2O 0.5 mol/L H2SO4 solution, the platinum particle modified porous silver electrode had the highest catalytic activity for formaldehyde oxidation when the deposition rate was 10 mV/s, and the number of cycles was 5 cycles. The whole electrodeposition process and the kinetic process of the modified electrode catalyzed by formaldehyde were controlled by diffusion. The morphology of the porous electrode was not changed after the deposition of platinum on the porous silver electrode. The platinum content of the modified electrode was 3.12 and the total amount of platinum deposited was about 100 渭 g. The electrocatalytic oxidation activity and stability of the porous silver electrode and its modified electrode for formaldehyde were compared. The results showed that the oxidation activation energy of formaldehyde on the modified electrode was low, the reaction rate was high, the activity was high, and the stability was improved obviously.
【學(xué)位授予單位】：大連交通大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TB383.4;O614.122
【相似文獻(xiàn)】
相關(guān)期刊論文 前10條
1 關(guān)抗芳;;新法制備銀—硫化銀電極[J];杭州化工;1983年01期
2 孫玉華;鮑芳;顧偉;姚建林;顧仁敖;;銀電極表面上C_(60)薄膜的表面增強(qiáng)拉曼光譜研究[J];光譜學(xué)與光譜分析;2007年04期
3 周國(guó)定,蔡生民,童汝亭;鋅銀電池中氧化銀電極的光電化學(xué)研究[J];物理化學(xué)學(xué)報(bào);1989年05期
4 陳昌國(guó),林惠瓊,黃宗卿;銀電極表面氧化物的形成與轉(zhuǎn)變[J];物理化學(xué)學(xué)報(bào);1992年01期
5 陳勝利，吳秉亮，楊漢西;電化學(xué)石英晶體微天平對(duì)銀電極氧化還原過程的研究[J];高等學(xué)�；瘜W(xué)學(xué)報(bào);1994年01期
6 劉光達(dá);銀電極電解氫氧化鈉水溶液的陽(yáng)極反應(yīng)[J];大學(xué)化學(xué);1995年04期
7 ，
本文編號(hào)：2272459
本文鏈接：http://sikaile.net/kejilunwen/cailiaohuaxuelunwen/2272459.html
最近更新
教材專著
