Insight into the bimetallic structure sensibility of catalytic nitrate reduction over Pd-Cu nanocrystals  

作　　者：Zhiqiang Zhang Wenhang Li Cailin Zheng Kunyu Chen Heliang Pang Wenxin Shi Jinsuo Lu 

机构地区：[1]School of Environmental and Municipal Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China [2]Key Laboratory of Northwest Water Resources,Environment and Ecology,Ministry of Education,Xian 710055,China [3]State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology,Harbin 150090,China [4]Construction engineering quality and safety supervision center station,House and Urban Rural Development Department of Ankang,Ankang 725000,China [5]College of Urban Construction and Environmental Engineering,Chongqing University,Chongqing 400044,China

出　　处：《Journal of Environmental Sciences》2025年第3期221-233,共13页环境科学学报(英文版)

基　　金：support from the National Natural Science Foundation of China(Nos.52370100,52000146,and 51978098);China Postdoctoral Science Foundation(No.2020M673351).

摘　　要：Catalytic reduction of nitrate over bimetallic catalysts has emerged as a technology for sustainable treatment of nitrate-containing groundwater.However,the structure of bimetallic has been much less investigated for catalyst optimization.Herein,two main types of Pd-Cu bimetallic nanocrystal structures,heterostructure and intermetallic,were prepared and characterized using high-resolution transmission electron microscopy(HRTEM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).The results show that two individual Pd and Cu nanocrystals with a mixed interface exist in the heterostructure nanocrystals,while Pd and Cu atoms are uniformly distributed across the intermetallic Pd-Cu nanocrystals.The catalytic nitrate reduction experiments were carried out in a semibatch reactor under constant hydrogen flow.The nitrate conversion rate of the heterostructure Pd-Cu nanocrystals supported onα-Al_(2)O_(3),γ-Al_(2)O_(3),SBA-15,and XC-72R exhibited 3.82-,6.76-,4.28-,2.44-fold enhancements relative to the intermetallic nanocrystals,and the nitrogen and nitrite were the main products for the heterostructure and intermetallic Pd-Cu nanocrystals,respectively.This indicates that the catalytic nitrate reduction over Pd-Cu catalyst is sensitive to the bimetallic structures of the catalysts,and heterostructure bimetallic nanocrystals exhibit better catalytic performances on both the activity and selectivity,which may provide new insights into the design and optimization of catalysts to improve catalytic activity and selectivity for nitrate reduction in water.

关 键 词：Catalytic nitrate reduction Pd-Cu bimetallic catalyst HETEROSTRUCTURE INTERMETALLIC Activity and selectivity 

分 类 号：O64[理学—物理化学]