Mechanistic Study of CO2 Photoreduction with H2O on Cu/TiO2 Nanocomposites by in Situ X-ray Absorption and Infrared Spectroscopies

X射线吸收光谱法 光催化 漫反射红外傅里叶变换 煅烧 吸收(声学) 吸附 光化学 傅里叶变换红外光谱 红外光谱学 氧气 化学 吸收光谱法 氧化还原 催化作用 红外线的 材料科学 无机化学 物理化学 化学工程 冶金 复合材料 有机化学 量子力学 光学 工程类 生物化学 物理
作者
Lianjun Liu,Cunyu Zhao,Jeffrey T. Miller,Ying Li
出处
期刊:Journal of Physical Chemistry C [American Chemical Society]
卷期号:121 (1): 490-499 被引量:113
标识
DOI:10.1021/acs.jpcc.6b10835
摘要

Cu/TiO2 composites are extensively studied for photocatalytic reduction of CO2 with H2O, but the roles of Cu species (Cu2+, Cu+, or Cu0) is not well understood, and the photocatalyst deactivation mechanism is seldom addressed. In this work, we have employed in situ techniques, i.e., X-ray absorption spectroscopy (XAS) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), to explore the surface chemistry of Cu/TiO2 composites under CO2 photoreduction environment. We found that the air-calcined Cu/TiO2 (Cu/Ti(air)) surface was dominated by isolated Cu2+ sites, while the one post-treated with H2 at 200 °C (Cu/Ti(H2)) was rich in Cu+ and oxygen vacancy (VO). Cu/Ti(H2) showed more than 50% higher activity than Cu/Ti(air) for CO2 photoreduction to CO, mainly resulting from the synergy of Cu+, OH groups, and VO that could scavenge holes to enhance electron transfer, provide CO2 adsorption sites, and facilitate the activation and conversion of the adsorbed CO2 (HCO3– and CO2–). Meanwhile, the consumption of OH groups and Cu+ active sites by holes may result in the deactivation of Cu/Ti(H2). Moreover, in situ XAS results directly demonstrated that (1) the photoinduced oxidation of Cu+ to Cu2+ changed the surrounding environments of Cu by increasing the coordination number; (2) thermal treatment by H2 could not fully recover the OH and Cu+ sites to their original states; and (3) adding hole scavengers (e.g., methanol) maintained or even increased the more active Cu+ species from the photoreduction of Cu2+, thus leading to a higher and more stable CO2 reduction activity. Findings in this work and the application of in situ XAS technique will help develop a more efficient photocatalyst for CO2 photoreduction and advance the understanding of the reaction mechanism and surface chemistry.
最长约 10秒,即可获得该文献文件

科研通智能强力驱动
Strongly Powered by AbleSci AI
更新
PDF的下载单位、IP信息已删除 (2025-6-4)

科研通是完全免费的文献互助平台,具备全网最快的应助速度,最高的求助完成率。 对每一个文献求助,科研通都将尽心尽力,给求助人一个满意的交代。
实时播报
DijiaXu应助猪猪hero采纳,获得10
1秒前
2秒前
悦耳静枫完成签到,获得积分10
2秒前
霍骁发布了新的文献求助10
3秒前
XAN关注了科研通微信公众号
4秒前
4秒前
5秒前
简因完成签到 ,获得积分10
6秒前
7秒前
11发布了新的文献求助10
8秒前
8秒前
9秒前
不学无术发布了新的文献求助10
11秒前
hanna完成签到 ,获得积分10
11秒前
12秒前
科研通AI5应助科研通管家采纳,获得10
12秒前
斯文败类应助科研通管家采纳,获得10
12秒前
小二郎应助科研通管家采纳,获得10
13秒前
领导范儿应助科研通管家采纳,获得10
13秒前
Orange应助科研通管家采纳,获得10
13秒前
香蕉觅云应助科研通管家采纳,获得10
13秒前
FashionBoy应助科研通管家采纳,获得10
13秒前
桐桐应助科研通管家采纳,获得10
13秒前
彭于晏应助科研通管家采纳,获得10
13秒前
慕青应助科研通管家采纳,获得10
13秒前
科研通AI5应助科研通管家采纳,获得10
13秒前
爆米花应助科研通管家采纳,获得10
13秒前
czh应助科研通管家采纳,获得20
13秒前
qqshown完成签到,获得积分10
14秒前
14秒前
14秒前
14秒前
14秒前
16秒前
量子星尘发布了新的文献求助10
16秒前
XAN发布了新的文献求助10
17秒前
DijiaXu应助必过六级采纳,获得10
19秒前
小门发布了新的文献求助10
19秒前
20秒前
Afaq发布了新的文献求助10
20秒前
高分求助中
A new approach to the extrapolation of accelerated life test data 1000
ACSM’s Guidelines for Exercise Testing and Prescription, 12th edition 500
‘Unruly’ Children: Historical Fieldnotes and Learning Morality in a Taiwan Village (New Departures in Anthropology) 400
Indomethacinのヒトにおける経皮吸収 400
Phylogenetic study of the order Polydesmida (Myriapoda: Diplopoda) 370
基于可调谐半导体激光吸收光谱技术泄漏气体检测系统的研究 350
Robot-supported joining of reinforcement textiles with one-sided sewing heads 320
热门求助领域 (近24小时)
化学 材料科学 医学 生物 工程类 有机化学 生物化学 物理 内科学 纳米技术 计算机科学 化学工程 复合材料 遗传学 基因 物理化学 催化作用 冶金 细胞生物学 免疫学
热门帖子
关注 科研通微信公众号,转发送积分 3989263
求助须知:如何正确求助?哪些是违规求助? 3531418
关于积分的说明 11253814
捐赠科研通 3270066
什么是DOI,文献DOI怎么找? 1804884
邀请新用户注册赠送积分活动 882084
科研通“疑难数据库(出版商)”最低求助积分说明 809136