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Liu XH, Lu T, Jiao X, Jiang Z, Chen C, Wang Y, Jian Y, He C. Formaldehyde Ambient-Temperature Decomposition over Pd/Mn 3O 4-MnO Driven by Active Sites' Self-Tandem Catalysis. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:1752-1762. [PMID: 38190653 DOI: 10.1021/acs.est.3c06876] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2024]
Abstract
The widespread presence of formaldehyde (HCHO) pollutant has aroused significant environmental and health concerns. The catalytic oxidation of HCHO into CO2 and H2O at ambient temperature is regarded as one of the most efficacious and environmentally friendly approaches; to achieve this, however, accelerating the intermediate formate species formation and decomposition remains an ongoing obstacle. Herein, a unique tandem catalytic system with outstanding performance in low-temperature HCHO oxidation is proposed on well-structured Pd/Mn3O4-MnO catalysts possessing bifunctional catalytic centers. Notably, the optimized tandem catalyst achieves complete oxidation of 100 ppm of HCHO at just 18 °C, much better than the Pd/Mn3O4 (30%) and Pd/MnO (27%) counterparts as well as other physical tandem catalysts. The operando analyses and physical tandem investigations reveal that HCHO is primarily activated to gaseous HCOOH on the surface of Pd/Mn3O4 and subsequently converted to H2CO3 on the Pd/MnO component for deep decomposition. Theoretical studies disclose that Pd/Mn3O4 exhibits a favorable reaction energy barrier for the HCHO → HCOOH step compared to Pd/MnO; while conversely, the HCOOH → H2CO3 step is more facilely accomplished over Pd/MnO. Furthermore, the nanoscale intimacy between two components enhances the mobility of lattice oxygen, thereby facilitating interfacial reconstruction and promoting interaction between active sites of Pd/Mn3O4 and Pd/MnO in local vicinity, which further benefits sustained HCHO tandem catalytic oxidation. The tandem catalysis demonstrated in this work provides a generalizable platform for the future design of well-defined functional catalysts for oxidation reactions.
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Affiliation(s)
- Xiao-He Liu
- Department of Environmental Engineering, College of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710054, P. R. China
- State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, PR China
| | - Tong Lu
- Department of Environmental Engineering, College of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710054, P. R. China
- State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, PR China
| | - Xinguo Jiao
- Department of Environmental Engineering, College of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710054, P. R. China
| | - Zeyu Jiang
- State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, PR China
| | - Changwei Chen
- State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, PR China
| | - Yadi Wang
- State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, PR China
| | - Yanfei Jian
- State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, PR China
| | - Chi He
- State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi'an Jiaotong University, Xi'an 710049, Shaanxi, PR China
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Liu Y, Li Z, Liu XH, Pinna N, Wang Y. Atomically precise Au xAg 25-x nanoclusters with a modulated interstitial Au-Ag microenvironment for enhanced visible-light-driven photocatalytic hydrogen evolution. NANOSCALE HORIZONS 2023; 8:1435-1439. [PMID: 37615060 DOI: 10.1039/d3nh00235g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Abstract
Herein, we report the study of atomically precise AuxAg25-x nanoclusters (NCs) toward photocatalytic hydrogen evolution. The incorporation of Au atoms into Ag25 NCs not only narrowed the HOMO-LUMO gaps but also created an interstitial Au-Ag microenvironment, which promoted the photogenerated charge carrier utilization and optimized the reaction dynamics.
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Affiliation(s)
- Ye Liu
- Department of Chemistry, IRIS Adlershof & The Center for the Science of Materials Berlin, Humboldt-Universität zu Berlin, 12489, Berlin, Germany.
| | - Zhi Li
- School of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710049, Shaanxi, China
| | - Xiao-He Liu
- School of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710049, Shaanxi, China
| | - Nicola Pinna
- Department of Chemistry, IRIS Adlershof & The Center for the Science of Materials Berlin, Humboldt-Universität zu Berlin, 12489, Berlin, Germany.
| | - Yu Wang
- Department of Chemistry, IRIS Adlershof & The Center for the Science of Materials Berlin, Humboldt-Universität zu Berlin, 12489, Berlin, Germany.
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