CuNi双金属MOFs串联催化促进硝酸盐还原合成氨

doi:10.15541/jim20250321

无机材料学报 ›› 2026, Vol. 41 ›› Issue (5): 628-636.DOI: 10.15541/jim20250321 CSTR: 32189.14.jim20250321

CuNi双金属MOFs串联催化促进硝酸盐还原合成氨

王萌¹^,²(), 曹磊磊¹, 苟王燕¹, 程娅伊¹, 战琪¹, 原孟磊²()

¹ 西安航空学院材料工程学院, 西安 710077
² 西北工业大学材料学院, 西安 710072

收稿日期:2025-08-01 修回日期:2025-09-30 出版日期:2025-10-17 网络出版日期:2025-10-17
通讯作者: 原孟磊, 副教授. E-mail: mlyuan@nwpu.edu.cn
作者简介:王萌(1989-), 女, 博士. E-mail: m_wang@xaau.edu.cn
基金资助:
国家自然科学基金(22578364);国家自然科学基金(52302310);陕西省自然科学基础研究计划项目(2025JC-YBQN-150);陕西省自然科学基础研究计划项目(2025JC-YBMS-136);陕西省教育厅专项科研计划项目(24JK0496)

Tandem Catalysis of CuNi Bimetallic MOFs Boosting Nitrate Reduction for Ammonia Production

WANG Meng¹^,²(), CAO Leilei¹, GOU Wangyan¹, CHENG Yayi¹, ZHAN Qi¹, YUAN Menglei²()

¹ School of Materials Engineering, Xihang University, Xi’an 710077, China
² School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072, China

Received:2025-08-01 Revised:2025-09-30 Published:2025-10-17 Online:2025-10-17
Contact: YUAN Menglei, associate professor. E-mail: mlyuan@nwpu.edu.cn
About author:WANG Meng (1989-), female, PhD. E-mail: m_wang@xaau.edu.cn
Supported by:
National Natural Science Foundation of China(22578364);National Natural Science Foundation of China(52302310);Shaanxi Province Natural Science Basic Research Program(2025JC-YBQN-150);Shaanxi Province Natural Science Basic Research Program(2025JC-YBMS-136);Scientific Research Program of Shaanxi Provincial Department of Education(24JK0496)

摘要/Abstract

摘要：

电催化硝酸盐还原反应(NO₃RR)是一种生产氨和净化废水的绿色技术, 但是其反应过程会与析氢反应竞争, 并且造成亚硝酸盐中间体积累。设计和构筑具有不同催化特性的双活性位点可以提高反应活性, 进而通过串联催化策略(NO₃^-→NO₂^-→NH₃)显著提升氨的生成速率与选择性。本研究以结构明确的金属有机框架(MOFs)为模板, 通过简单的水热法构筑了CuNi双金属MOFs串联催化体系。研究结果表明, Cu活性位点可高效催化NO₃^-还原为NO₂^-, Ni位点展现出优异的活性氢物种^*H供应能力及NO₂^-转化效率, 二者形成高效的串联催化机制, 实现了高达90.1%的氨合成法拉第效率和28.8 mg·h^-1·mg_cat^-1的氨产率。经过多次循环测试后, 双金属MOFs催化剂的合成氨性能未出现衰减, 表现出优异的循环稳定性。本研究可为高性能串联催化剂的设计与优化提供新的见解。

关键词: 合成氨, 硝酸盐还原反应, 双金属, 金属有机框架, 串联催化

Abstract:

Electrocatalytic nitrate reduction reaction (NO₃RR), as a green technology for producing ammonia and purifying wastewater, faces challenges in terms of nitrite intermediate accumulation and competitive hydrogen evolution reactions. Tandem catalytic strategy (NO₃^-→NO₂^-→NH₃) is expected to significantly improve the rate and selectivity of ammonia production. Therefore, designing and constructing dual active sites with different catalytic properties contributes to improving reaction activity. Herein, a CuNi bimetallic metal organic framework (MOF) tandem catalytic system using well-defined MOFs as templates was constructed through simple hydrothermal synthesis. The research results indicated that Cu active sites could efficiently catalyze the reduction of NO₃^- to NO₂^-, while Ni sites exhibited excellent active hydrogen species ^*H supply capacity and NO₂^- conversion efficiency, forming an efficient tandem catalytic mechanism with Cu sites, and achieving a Faraday efficiency of up to 90.1% for ammonia synthesis and an ammonia yield of 28.8 mg·h^-1·mg_cat^-1. In addition, the bimetallic MOFs catalyst showed excellent cycling stability without any degradation in ammonia synthesis after multiple cycling tests. This work provides new insights for the design and optimization of high-performance tandem catalysts.

Key words: ammonia production, nitrate reduction reaction, bimetallic, metal organic framework, tandem catalysis

中图分类号:

O646

王萌, 曹磊磊, 苟王燕, 程娅伊, 战琪, 原孟磊. CuNi双金属MOFs串联催化促进硝酸盐还原合成氨[J]. 无机材料学报, 2026, 41(5): 628-636.

WANG Meng, CAO Leilei, GOU Wangyan, CHENG Yayi, ZHAN Qi, YUAN Menglei. Tandem Catalysis of CuNi Bimetallic MOFs Boosting Nitrate Reduction for Ammonia Production[J]. Journal of Inorganic Materials, 2026, 41(5): 628-636.

图/表 17

图1 合成催化剂的SEM照片

Fig. 1 SEM images of the prepared catalysts (a) Ni-BDP; (b) CuNi-BDP; (c) Cu2Ni-BDP

图2 CuNi-BDP的(a) TEM照片和(b)元素分布图

Fig. 2 (a) TEM image and (b) elemental mappings of CuNi-BDP

图3 合成催化剂的XRD图谱

Fig. 3 XRD patterns of the prepared catalysts

图4 合成催化剂的XPS谱图

Fig. 4 XPS spectra of the prepared catalysts (a, b) Total surveys of (a) Ni-BDP and (b) CuNi-BDP; (c, d) High resolution XPS spectra of (c) Ni2p and (d) Cu2p for Ni-BDP and CuNi-BDP

图5 合成催化剂的FT-IR光谱图

Fig. 5 FT-IR spectra of the prepared catalysts

图6 电催化NO3RR性能测试

Fig. 6 Electrocatalytic activity for NO3RR (a) LSV curves of Ni-BDP, CuNi-BDP and Cu2Ni-BDP in 1 mol/L KOH+0.1 mol/L KNO3; (b) NH3 yield rates and (c) FE at various potential for Ni-BDP, CuNi-BDP and Cu2Ni-BDP; (d) Double-layer capacitance and (e) Nyquist plots of Ni-BDP, CuNi-BDP and Cu2Ni-BDP; (f) Cycling tests of CuNi-BDP at -0.5 V (vs. RHE). Colorful figures are available on website

图7 CuNi-BDP副产物NO2-的(a)产率和(b) FE

Fig. 7 (a) Yield rates and (b) FE of NO2- byproduct for CuNi-BDP

图8 反应机理图

Fig. 8 Schematic diagram of reaction mechanism

图S1 Ni-BDP在(a)不同电解液中的LSV曲线和(b)不同电位下的计时电流(CA)曲线

Fig. S1 (a) LSV curves in different electrolytes and (b) chronoamperometric (CA) curves at various potential of Ni-BDP

图S2 CuNi-BDP在(a)不同电解液中的LSV曲线和(b)不同电位下的CA曲线

Fig. S2 (a) LSV curves in different electrolytes and (b) CA curves at various potential of CuNi-BDP

图S3 Cu2Ni-BDP在(a)不同电解液中的LSV曲线和(b)不同电位下的CA曲线

Fig. S3 (a) LSV curves in different electrolytes and (b) CA curves at various potential of Cu2Ni-BDP

图S4 (a)不同浓度NH3的UV-Vis光谱和(b)对应的标准曲线

Fig. S4 (a) UV-Vis spectra of NH3 with different concentrations and (b) corresponding calibration curve

图S5 (a)不同浓度NO2-的UV-Vis光谱和(b)对应的标准曲线

Fig. S5 (a) UV-Vis spectra of NO2- with different concentrations and (b) corresponding calibration curve

图S6 催化剂在不同扫描速率下的CV曲线

Fig. S6 CV curves at different scan rates for catalysts (a) Ni-BDP; (b) CuNi-BDP; (c) Cu2Ni-BDP

图S7 CuNi-BDP催化剂在NO3RR循环测试后的(a) SEM照片、(b) XRD图谱和(c, d) XPS谱图

Fig. S7 (a) SEM image, (b) XRD pattern and (c, d) XPS spectra of CuNi-BDP after NO3RR cycle test

表S1 CuNi-BDP和Cu2Ni-BDP的ICP-MS数据

Table S1 ICP-MS data of CuNi-BDP and Cu2Ni-BDP

Catalyst	Element	Metal content/% (in mass)	Ni/Cu atomic ratio
CuNi-BDP	Ni	15.66	8.56
CuNi-BDP	Cu	1.98	8.56
Cu₂Ni-BDP	Ni	13.45	3.99
Cu₂Ni-BDP	Cu	3.65	3.99

表S2 不同双金属催化剂的NO3RR性能对比

Table S2 Comparison of NO3RR performance for different bimetallic catalysts

Catalyst	NO₃^- concentration	NH₃ FE	NH₃ yield rate	Ref.
CuNi-BDP	0.1 mol/L	90.1% (-0.5 V)	28.8 mg·h^-1·mg_cat^-1 (-0.7 V)	This work
Fe/Cu-HNG	0.1 mol/L	92.5% (−0.3 V)	18.4 mg·h^-1·mg_cat^-1(-0.5 V)	[S1]
Cu₇Ni₃/OMC	500 mg/L	78.9% (−0.4 V)	0.237 mg·h^-1·mg_cat^-1(-0.8 V)	[S2]
Co_3-_xNi_xO₄	0.1 mol/L	94.9% (-1.0 V)	20 mg·h^-1·cm^-2(-1.0 V)	[S3]
Fe-V₂O₅	0.1 mol/L	97.1% (-0.7 V)	12.5 mg·h^-1·cm^-2(-0.7 V)	[S4]
Fe₃O₄@TiO₂/TP	0.1 mol/L	88.4% (-0.7 V)	12.4 mg·h^-1·cm^-2(-1.1 V)	[S5]
Ru₁Cu₁₀/rGO	100 mg/L	98% (-0.05 V)	6.46 mg·h^-1·cm^-2(-0.6 V)	[S6]
Cu₄₉Fe₁	200 mg/L	94.5% (-0.74 V)	3.91 mg·h^-1·cm^-2(-0.74 V)	[S7]
Au/Cu SAAs	100 mg/L	98.3% (-0.8 V)	3.28 mg·h^-1·cm^-2(-0.8 V)	[S8]
Ru/WO₃₋_x	0.1 mol/L	95.1% (0 V)	12.38 mg·h^-1·cm^-2(-0.6 V)	[S9]
Ni₃Co₆S₈	50 mg/L	85.3% (-0.4 V)	2.338 mg·h^-1·cm^-2 (-0.4 V)	[S10]
Pt-Fe₃O₄	0.1 mol/L	80.7% (-0.8 V)	5.42 mg·h^-1·mg^-1 (-0.8 V)	[S11]
Cu₃P-Ni₂P/CP	200 mg/L	95.25% (-0.6 V)	3.21 mg·h^-1·cm^-2(-0.6 V)	[S12]
Cu-Co₃O₄	5 mmol/L	93.77% (-1.0 V)	3.23 mg·h^-1·cm^-2(-1.0 V)	[S13]
Cu_xCo_yO-NC	0.1 mol/L	97.9% (-0.79 V)	7.65 mg·h^-1·cm^-2(-0.79 V)	[S14]
Pd-CoO_x	0.1 mol/L	98.7% (-0.4 V)	30.3 mg·h^-1·cm^-2(-0.4 V)	[S15]

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CuNi双金属MOFs串联催化促进硝酸盐还原合成氨

Tandem Catalysis of CuNi Bimetallic MOFs Boosting Nitrate Reduction for Ammonia Production

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