基于丝网印刷法制备的Pd/TiO_(2)薄膜用于光催化CO_(2)转化  

Preparation of Pd/TiO_(2) film based on screen-printing method and its photocatalytic performance in CO_(2) conversion

作　　者：于筱航 邱鹏远 钟山 宋磊 李红娇 唐思扬 梁斌[1,3] YU Xiaohang;QIU Pengyuan;ZHONG Shan;SONG Lei;LI Hongjiao;TANG Siyang;LIANG Bin(School of Chemical Engineering,Sichuan University,Chengdu 610207,Sichuan,China;SINOPEC Shanghai Research Institute of Petrochemical Technology Co.,Ltd.,Shanghai 201208,China;Institute of New Energy and Low-Carbon Technology,Sichuan University,Chengdu 610207,Sichuan,China)

机构地区：[1]四川大学化学工程学院,四川成都610207 [2]中石化(上海)石油化工研究院有限公司,上海201208 [3]四川大学新能源与低碳技术研究院,四川成都610207

出　　处：《低碳化学与化工》2023年第3期69-77,97,共10页Low-Carbon Chemistry and Chemical Engineering

基　　金：国家自然科学基金(22138008)。

摘　　要：光催化剂的固载化对其应用和回收有重要意义。首先以钛片作基底,乙基纤维素和松油醇作粘结剂,采用丝网印刷法制备TiO_(2)薄膜(w-xfilm-y,其中w为粘结剂与TiO_(2)质量比,x为印刷层数,y为焙烧温度),最后用光沉积法负载Pd颗粒制得Pd/TiO_(2)薄膜(负载型薄膜催化剂w-xfilm-y-0.18Pd,其中0.18为Pd的质量分数)。以颗粒催化剂(P-z-Pd,其中z为Pd质量分数)作对照,测试了两种气氛(CO_(2)和H_(2)、CO_(2)和C2H6)下w-xfilm-y-0.18Pd的光催化CO_(2)转化性能。采用XRD、HRTEM和XPS等表征了w-xfilm-y-0.18Pd的结构和活性中心,采用UV-Vis DRS和ESR技术分析了w-xfilm-y-0.18Pd的光学性质和活性物种。结果表明,丝网印刷一层的TiO_(2)薄膜的厚度为5μm,负载Pd颗粒后TiO_(2)薄膜的光吸收能力增强,TiO_(2)颗粒固载化不影响TiO_(2)的晶型,但影响了Pd颗粒的表面分散,导致Pd颗粒的粒径从2.3 nm增加到3.9 nm。w-xfilm-y-0.18Pd表面负载的Pd颗粒作为电子捕获阱,定向迁移光生电子至Pd颗粒负载面进行富集,强化了CO_(2)加氢制CH_(4)性能,与P-0.25-Pd相比,CH_(4)生成速率从26.0μmol/(g·h)提高到198.5μmol/(g·h)。w-xfilm-y-0.18Pd负载的Pd颗粒粒径增大,光照时羟基自由基数量减少,导致其催化CO_(2)氧化C2H6脱氢制C2H_(4)性能较差,与P-0.25-Pd相比,C2H_(4)生成速率从479.9μmol/(g·h)降低至42.5μmol/(g·h)。The immobilization of photocatalyst is important for its application and recovery.In this work,TiO_(2) film(w-xfilm-y,w is the mass ratio of binder to TiO_(2),x is the number of printing layers,y is the roasting temperature)was firstly prepared by screen printing method with titanium sheet as base and ethyl cellulose and terpineol as binder.Finally,Pd nanoparticles were loaded onto the TiO_(2) film using the photodeposition method to obtain Pd/TiO_(2)(supported thin film catalysts w-xfilm-y-0.18Pd,0.18 is the mass fraction of Pd).A comparative study was conducted using particle catalyst(P-z-Pd,z is the mass fraction of Pd)as control group to assess the photocatalytic CO_(2) conversion performance of w-xfilm-y-0.18Pd in two different atmospheres(CO_(2) and H_(2),CO_(2) and C2H6).The structure and active center of the w-xfilm-y-0.18Pd were characterized by XRD,HRTEM and XPS techniques,and the optical property and active species of the catalyst were analyzed using UV-Vis DRS and ESR techniques.The results show that the thickness of the TiO_(2) film,screen-printed in a single layer,is 5μm.After loading Pd particles onto the TiO_(2) film,the light absorption capacity of the TiO_(2) film is enhanced.The immobilization of the TiO_(2) particles does not affect the crystal structure of TiO_(2),while it can affect the surface dispersion of metal particles,resulting in an increase of Pd particle size from 2.3 nm to 3.9 nm.Pd particles loaded on the surface of w-xfilm-y-0.18Pd act as electrons capture trap,and directionally migrates photogenerated electrons to the load surface of Pd particles for enrichment,which enhances the performance of CO_(2) hydrogenation to CH_(4).Comparing with P-0.25-Pd,the CH_(4) production rate of w-xfilm-y-0.18Pd increases from 26.0μmol/(g·h)to 198.5μmol/(g·h).The size of Pd particles loaded on w-xfilm-y-0.18Pd increases and the number of hydroxyl radicals decreases under light,resulting in the poor catalytic performance in catalyzing CO_(2) oxidation of C2H6 dehydrogenation to C2H_(4).Compa

关 键 词：固载化 光催化 丝网印刷 TiO_(2)薄膜 PD CO_(2)加氢 烷烃脱氢 

分 类 号：TQ034[化学工程]