摘要
以MnCl_(2)为原料,聚乙烯醇(PVA)为稳定剂,利用PVA介导沉淀法制备Mn_(3)O_(4)纳米粒子(PVA/Mn_(3)O_(4)),进一步将冻干的PVA/Mn_(3)O_(4)复合物炭化制备了超小尺寸的Mn_(3)O_(4)-C催化剂。使用XRD、XPS、TEM、BET表征制备材料的结构和形貌,发现PVA能够有效减小Mn_(3)O_(4)在制备过程中的聚集和长大。无PVA介导沉淀法制备的Mn_(3)O_(4)-P平均粒径为(38.8±9.3)nm。加入PVA后,制备过程中PVA分子链间的Mn_(3)O_(4)纳米粒子平均粒径为(3.2±0.8)nm,经过Ar保护炭化处理后,平均粒径为(4.5±1.2)nm的Mn_(3)O_(4)纳米粒子被均匀固定在碳基底上。制备的Mn_(3)O_(4)-C催化剂具有高效的类芬顿催化降解亚甲基蓝(MB)的能力,在MB质量浓度为40 mg/L的40 mL溶液中,催化剂质量浓度为75 mg/L,H_(2)O_(2)投加量为4 mL,反应时间为40 min,反应温度为80℃的条件下,MB的降解率为94.4%。催化剂经过3次循环使用后,MB的降解率保持在91.1%,且碳基底上的Mn_(3)O_(4)纳米粒子结构和形貌与使用前相似。
An ultrafine carbon-supported Mn_(3)O_(4)nanocatalyst was synthesized from carbonization of lyophilized PVA/Mn_(3)O_(4)complex,which was prepared via poly(vinyl alcohol)(PVA)mediated precipitation of MnCl_(2),and characterized by XRD,XPS,TEM and BET for structure and morphology analysis.The results showed that PVA could effectively reduce the aggregation and growth of Mn_(3)O_(4)nanoparticles during the preparation process.The Mn_(3)O_(4)nanoparticles prepared in absence of PVA(Mn_(3)O_(4)-P)presented a average particle size of(38.8±9.3)nm,while that of Mn_(3)O_(4)nanoparticles dispersed in the PVA molecular chains was(3.2±0.8)nm.Meanwhile,the Ar-protected carbonization treatment of the freeze-dried PVA/Mn_(3)O_(4)complex led to uniform immobilization of Mn_(3)O_(4)nanoparticles on the carbon substrate with a average particle size of(4.5±1.2)nm.The Mn_(3)O_(4)-C catalyst obtained exhibited excellent catalytic performance for Fenton-like degradation of methylene blue(MB).Mn_(3)O_(4)-C promoted the degradation rate of 40 mL MB solution with a mass concentration of 40 mg/L to 94.4% under the conditions of catalyst mass concentration of 75 mg/L,H_(2)O_(2)dosage of 4 mL,reaction time of 40 min and reaction temperature of 80℃.Moreover,Mn_(3)O_(4)-C showed better recycle stability compared with the Mn_(3)O_(4)nanoparticles prepared in absence of PVA.The degradation rate for MB remained at 91.1% even after the catalyst was recycled for 3times,and the structure and morphology of Mn_(3)O_(4)nanoparticles on the carbon substrate were similar to those freshly prepared.
作者
陈润奇
颜雨坤
温国栋
周杨韬
那铎
张劲松
CHEN Runqi;YAN Yukun;WEN Guodong;ZHOU Yangtao;NA Duo;ZHANG Jinsong(Shenyang National Laboratory for Materials Science,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,Liaoning,China;School of Materials Science and Engineering,University of Science and Technology of China,Shenyang 110016,Liaoning,China)
出处
《精细化工》
EI
CAS
CSCD
北大核心
2023年第3期592-599,607,共9页
Fine Chemicals
基金
辽宁省自然科学基金(2021-MS-013)
沈阳材料科学国家研究中心青年科学基金项目(L2019F6,L2019F15和L2019F30)。
作者简介
陈润奇(1994-),男,硕士生,E-mail:rqchen18s@imr.ac.cn;联系人:张劲松(1963-),男,研究员,E-mail:jszhang@imr.ac.cn。
