CeO2-Cu2O 2D/3D S型异质结界面促进有序电荷转移以实现高效光催化析氢

doi:10.3866/PKU.WHXB202302051

物理化学学报 >> 2023, Vol. 39 >> Issue (12): 2302051.doi: 10.3866/PKU.WHXB202302051

CeO₂-Cu₂O 2D/3D S型异质结界面促进有序电荷转移以实现高效光催化析氢

张利君¹^,², 吴有林¹, Tsubaki Noritatsu²^,*(), 靳治良¹^,*()

¹ 北方民族大学化学与化学工程学院，银川 750021
² 富山大学工学部，应用化学系，五福 3190，富山 930-8555，日本

收稿日期:2023-02-28 录用日期:2023-04-10 发布日期:2023-04-17
通讯作者: Tsubaki Noritatsu,靳治良 E-mail:tsubaki@eng.u-toyama.ac.jp;zl-jin@nun.edu.cn
基金资助:
国家自然科学基金(22062001);宁夏废弃食用油转化为清洁能源高附加值化学品创新团队和低品位资源高值化利用及环境化工一体化技术创新团队资助项目

2D/3D S-Scheme Heterojunction Interface of CeO₂-Cu₂O Promotes Ordered Charge Transfer for Efficient Photocatalytic Hydrogen Evolution

Lijun Zhang¹^,², Youlin Wu¹, Noritatsu Tsubaki²^,*(), Zhiliang Jin¹^,*()

¹ School of Chemistry and Chemical Engineering, North Minzu University, Yinchuan 750021, China
² Department of Applied Chemistry, Graduate School of Engineering, University of Toyama, Gofuku 3190, Toyama 930-8555, Japan

Received:2023-02-28 Accepted:2023-04-10 Published:2023-04-17
Contact: Noritatsu Tsubaki, Zhiliang Jin E-mail:tsubaki@eng.u-toyama.ac.jp;zl-jin@nun.edu.cn
Supported by:
the National Natural Science Foundation of China(22062001);the Innovative Team for Transforming Waste Cooking Oil into Clean Energy and High Value-Added Chemicals, Ningxia Low-Grade Resource High Value Utilization and Environmental Chemical Integration Technology Innovation Team Project

摘要/Abstract

摘要：

快速的本征载流子复合严重限制了CeO₂基催化材料的光催化活性。在这里，提出了一种异质结界面工程策略，合理地进行界面调节。构建了具有强电子相互作用的2D/3D S型异质结。合成了一种用于固定在2D CeO₂边缘的3D Cu₂O颗粒的复合光催化剂。密度泛函理论(DFT)第一性原理计算和实验结果表明，CeO₂和Cu₂O之间形成强耦合的S型异质结电子传输界面，实现了高效的载流子分离和传输。复合催化剂的光催化析氢活性在以三乙醇胺为牺牲剂的体系中得到大幅提高，是CeO₂的48倍。此外，CeO₂-Cu₂O光催化剂还具有高度稳定的光催化氢活性。这为在新型纳米复合结构中构建独特界面提供了一种通用策略。

关键词: CeO₂, Cu₂O, DFT, S型异质结, 光催化析氢

Abstract:

Rapid intrinsic carrier recombination severely restricts the photocatalytic activity of CeO₂-based catalytic materials. In this study, a heterogeneous interfacial engineering strategy is proposed to rationally perform interface modulation. A 2D/3D S-scheme heterojunction with strong electronic interactions was constructed. A composite photocatalyst was synthesized for the 3D Cu₂O particles anchored at the edge of 2D CeO₂. First-principles calculations (based on density functional theory) and the experimental results show that a strongly coupled S-scheme heterojunction electron transport interface is formed between CeO₂ and Cu₂O, resulting in efficient carrier separation and transfer. The photocatalytic hydrogen evolution activity of the composite catalyst is significantly improved in the system with triethanolamine as the sacrificial agent and is 48 times as that of CeO₂. In addition, the resulting CeO₂-Cu₂O photocatalyst affords highly stable photocatalytic hydrogen activity. This provides a general technique for constructing unique interfaces in novel nanocomposite structures.

Key words: CeO₂, Cu₂O, DFT, S-scheme heterostructure, Photocatalytic hydrogen evolution

张利君, 吴有林, Tsubaki Noritatsu, 靳治良. CeO₂-Cu₂O 2D/3D S型异质结界面促进有序电荷转移以实现高效光催化析氢[J]. 物理化学学报, 2023, 39(12), 2302051. doi: 10.3866/PKU.WHXB202302051

Lijun Zhang, Youlin Wu, Noritatsu Tsubaki, Zhiliang Jin. 2D/3D S-Scheme Heterojunction Interface of CeO₂-Cu₂O Promotes Ordered Charge Transfer for Efficient Photocatalytic Hydrogen Evolution[J]. Acta Phys. -Chim. Sin. 2023, 39(12), 2302051. doi: 10.3866/PKU.WHXB202302051

链接本文: https://www.whxb.pku.edu.cn/CN/10.3866/PKU.WHXB202302051

https://www.whxb.pku.edu.cn/CN/Y2023/V39/I12/2302051

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Samples	m(CeO₂)/g	V/mL		Atomic fraction
Samples	m(CeO₂)/g	0.1 mol∙L⁻¹ Cu(AC)₂∙H₂O	0.6 mol∙L⁻¹ NaOH	Ce	O	Cu
CCO-1	0.35	5	5	17.54%	74.54%	7.92%
CCO-2	0.35	10	10	18.80%	71.81%	9.39%
CCO-3	0.35	15	15	18.57%	70.74%	10.69%
CCO-4	0.35	20	20	17.87%	67.61%	14.53%

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CeO₂-Cu₂O 2D/3D S型异质结界面促进有序电荷转移以实现高效光催化析氢

2D/3D S-Scheme Heterojunction Interface of CeO₂-Cu₂O Promotes Ordered Charge Transfer for Efficient Photocatalytic Hydrogen Evolution

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