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2. Regulating Mono/Binuclear Fe Species in Framework Al-Rich Zeolites for Efficient Low-Temperature Alkane Oxidation

Author

Zhang, Qiang, primary, Li, Jialiang, additional, He, Guangyuan, additional, Li, Junyan, additional, Chen, Ziyi, additional, Zhang, Qing, additional, Wang, Chunyu, additional, Qi, Guodong, additional, Wang, Qiang, additional, Zhang, Peng, additional, Xu, Jun, additional, Terasaki, Osamu, additional, Mei, Donghai, additional, Liu, Zhongmin, additional, and Yu, Jihong, additional

Published
2024
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15. Enabling High-Performance All-Solid-State Batteries via Guest Wrench in Zeolite Strategy

Author

Chi, Xiwen, primary, Li, Malin, additional, Chen, Xiao, additional, Xu, Jun, additional, Yin, Xin, additional, Li, Shanghua, additional, Jin, Ziyue, additional, Luo, Zhaodi, additional, Wang, Xingxing, additional, Kong, Dechen, additional, Han, Meng, additional, Xu, Ji-Jing, additional, Liu, Zonghang, additional, Mei, Donghai, additional, Wang, Jiaao, additional, Henkelman, Graeme, additional, and Yu, Jihong, additional

Published
2023
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24. Elucidation of Active Sites in Aldol Condensation of Acetone over Single-Facet Dominant Anatase TiO2 (101) and (001) Catalysts

Author

Lin, Fan, Wang, Huamin, Zhao, Yuntao, Fu, Jia, Mei, Donghai, Jaegers, Nicholas R, Gao, Feng, and Wang, Yong

Subjects
Chemical Sciences, Physical Chemistry, Single-facet catalyst, anatase titania nanocrystals, aldol condensation, kinetics, density functional theory, surface hydroxyl, Chemical sciences
Abstract

Aldol condensations of carbonyl compounds for C-C bond formation are a very important class of reactions in organic synthesis and upgrading of biomass-derived feedstocks. However, the atomic level understanding of reaction mechanisms and structure-activity correlation on widely used transition metal oxide catalysts are limited due to the high degree of structural heterogeneity of catalysts such as commercial TiO2 powders. Here, we provide a deep understanding of the reaction mechanisms, kinetics, and structure-function relationships for vapor phase acetone aldol condensation through the controlled synthesis of two catalysts with high surface areas and clean, dominant facets, coupled with detailed characterization and kinetic studies that are further assisted by density functional theory (DFT) calculations. Temperature-dependent diffuse reflectance infrared Fourier transform spectroscopy showed the existence of abundant acetone bonded to surface hydroxyl groups (acetone-OsH) and acetone bonded to Lewis acid sites (acetone-Ti5c) on the surface of both {101} and {001} facet dominant TiO2. Intermolecular C-C coupling of theenolate intermediate from acetone-Ti5c and a vicinal acetone-OsH is a kinetically relevant step, which is consistent with kinetic and isotopic studies as well as DFT calculations. The {001} facet showed a lower apparent activation energy (or higher activity) than the {101} facet. This is likely caused by the weaker Lewis acid and Brønsted base strengths of the {001} facet which favors the reprotonation-desorption of the coupled intermediate, making the C-C coupling step more exothermic on the {001} facet and resulting in an earlier transition state with a lower activation barrier. It is also possible that the {001} facet has a smoother surface configuration and less steric hindrance during intermolecular C-C bond formation than the {101} facet.

Published
2021

31. Reversible Electrochemical Interface of Mg Metal and Conventional Electrolyte Enabled by Intermediate Adsorption

Author

Wang, Hui, Feng, Xuefei, Chen, Ying, Liu, Yi-Sheng, Han, Kee Sung, Zhou, Mingxia, Engelhard, Mark H, Murugesan, Vijayakumar, Assary, Rajeev S, Liu, Tianbiao Leo, Henderson, Wesley, Nie, Zimin, Gu, Meng, Xiao, Jie, Wang, Chongmin, Persson, Kristin, Mei, Donghai, Zhang, Ji-Guang, Mueller, Karl T, Guo, Jinghua, Zavadil, Kevin, Shao, Yuyan, and Liu, Jun

Abstract

Conventional electrolytes made by mixing simple Mg2+ salts and aprotic solvents, analogous to those in Li-ion batteries, are incompatible with Mg anodes because Mg metal readily reacts with such electrolytes, producing a passivation layer that blocks Mg2+ transport. Here, we report that, through tuning a conventional electrolyte - Mg(TFSI)2 (TFSI- is N(SO2CF3)2-) - with an Mg(BH4)2 cosalt, highly reversible Mg plating/stripping with a high Coulombic efficiency is achieved by neutralizing the first solvation shell of Mg cationic clusters between Mg2+ and TFSI- and enhanced reductive stability of free TFSI-. A critical adsorption step between Mg0 atoms and active Mg cation clusters involving BH4- anions is identified to be the key enabler for reversible Mg plating/stripping through analysis of the distribution of relaxation times (DRT) from operando electrochemical impedance spectroscopy (EIS), operando electrochemical X-ray absorption spectroscopy (XAS), nuclear magnetic resonance (NMR), and density functional theory (DFT) calculations.

Published
2020

39. Localized High-Concentration Sulfone Electrolytes for High-Efficiency Lithium-Metal Batteries

Author

Ren, Xiaodi, Chen, Shuru, Lee, Hongkyung, Mei, Donghai, Engelhard, Mark H, Burton, Sarah D, Zhao, Wengao, Zheng, Jianming, Li, Qiuyan, Ding, Michael S, Schroeder, Marshall, Alvarado, Judith, Xu, Kang, Meng, Y Shirley, Liu, Jun, Zhang, Ji-Guang, and Xu, Wu

Subjects
Affordable and Clean Energy, Macromolecular and Materials Chemistry
Abstract

To enable next-generation high-energy-density lithium (Li)-metal batteries (LMBs), an electrolyte that has simultaneous high Li-metal Coulombic efficiency (CE) and high anodic stability on cathodes is of significant importance. Sulfones are known for strong resistance against oxidation, yet their application in LMBs is restricted because of their poor compatibility with Li-metal anodes, high viscosity, and poor wettability. Here, we demonstrate that a high Li CE over 98% can be achieved in concentrated sulfone-based electrolytes. Furthermore, the viscosity and wettability issues of sulfones are resolved by the addition of a fluorinated ether, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, to form a localized high-concentration electrolyte (LHCE), which not only provides further improvement in Li CE (98.8%) but also remains anodically stable with high-voltage cathodes, suppresses Al corrosion, and enables LMBs to operate in a wide temperature range. As a result, significantly improved cycling performance of LMBs has been realized with sulfone-based LHCE. For high-voltage rechargeable lithium (Li)-metal batteries (LMBs), electrolytes with good stabilities on both the highly oxidative cathodes and the highly reductive Li-metal anodes are urgently desired. Sulfones have excellent oxidative stability, yet their high viscosity, poor wettability, and, in particular, incompatibility with Li anodes greatly hinder their applications in LMBs. Here, we demonstrate that a high Li Coulombic efficiency (CE) of 98.2% during repeated Li plating and stripping cycles can be realized in concentrated lithium bis(fluorosulfonyl)imide (LiFSI)-tetramethylene sulfone electrolyte. More importantly, the localized high-concentration electrolyte, formed by the dilution of the high-concentration electrolyte with a non-solvating fluorinated ether, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, solves the viscosity and wettability issues, further improves Li CE (98.8%), and improves the high-voltage (4.9 V) performance of LMBs with effective Al protection. High-voltage batteries with Li-metal anodes can offer desirable high energy densities. Despite their excellent oxidative stability, sulfones have various limitations to be useful in Li-metal batteries, in particular their instability with Li metal. Here, we achieved a high Li Coulombic efficiency of nearly 99% in a sulfone-based localized high-concentration electrolyte (LHCE) with the addition of a non-solvating co-solvent. In addition, this co-solvent is highly beneficial for realizing stable battery cycling up to 4.9 V.

Published
2018

40. Author Correction: Self-adaptive dual-metal-site pairs in metal-organic frameworks for selective CO2 photoreduction to CH4

Author

Li, Jian, primary, Huang, Hongliang, additional, Xue, Wenjuan, additional, Sun, Kang, additional, Song, Xiaohui, additional, Wu, Chunrui, additional, Nie, Lei, additional, Li, Yang, additional, Liu, Chengyuan, additional, Pan, Yang, additional, Jiang, Hai-Long, additional, Mei, Donghai, additional, and Zhong, Chongli, additional

Published
2022
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45. Confinement of CsPbBr3 Perovskite Nanocrystals into Extra‐large‐pore Zeolite for Efficient and Stable Photocatalytic Hydrogen Evolution.

Author

Gao, Shiqin, Wang, Bolun, Chen, Feijian, He, Guangyuan, Zhang, Tianjun, Li, Lin, Li, Junyan, Zhou, Yida, Feng, Binyao, Mei, Donghai, and Yu, Jihong

Subjects
NANOCRYSTALS, HYDROGEN evolution reactions, BAND gaps, ENERGY harvesting, DENSITY functional theory, ACTIVATION energy
Abstract

Metal halide perovskites (MHPs), renowned for their outstanding optoelectronic properties, hold significant promise as photocatalysts for hydrogen evolution reaction (HER). However, the low stability and insufficient exposure of catalytically active sites of bulky MHPs seriously impair their catalytic efficiency. Herein, we utilized an extra‐large‐pore zeolite ZEO‐1 (JZO) as a host to confine and stabilize the CsPbBr3 nanocrystals (3.4 nm) for boosting hydrogen iodide (HI) splitting. The as‐prepared CsPbBr3@ZEO‐1 featured sufficiently exposed active sites, superior stability in acidic media, along with intrinsic extra‐large pores of ZEO‐1 that were favorable for molecule/ion adsorption and diffusion. Most importantly, the unique nanoconfinement effect of ZEO‐1 led to the narrowing of the band gap of CsPbBr3, allowing for more efficient light utilization. As a result, the photocatalytic HER rate of the as‐prepared CsPbBr3@ZEO‐1 photocatalyst was increased to 1734 μmol ⋅ h−1 ⋅ g−1(CsPbBr3) under visible light irradiation compared with bulk CsPbBr3 (11 μmol ⋅ h−1 ⋅ g−1(CsPbBr3)), and the long‐term durability (36 h) can be achieved. Furthermore, Pt was incorporated with well‐dispersed CsPbBr3 nanocrystals into ZEO‐1, resulting in a significant enhancement in activity (4826 μmol ⋅ h−1 ⋅ g−1(CsPbBr3)), surpassing most of the Pt‐integrated perovskite‐based photocatalysts. Density functional theory (DFT) calculations and charge‐carrier dynamics investigation revealed that the dramatically boosted photocatalytic performance of Pt/CsPbBr3@ZEO‐1 could be attributed to the promotion of charge separation and transfer, as well as to the substantially lowered energy barrier for HER. This work highlights the advantage of extra‐large‐pore zeolites as the nanoscale platform to accommodate multiple photoactive components, opening up promising prospects in the design and exploitation of novel zeolite‐confined photocatalysts for energy harvesting and storage. [ABSTRACT FROM AUTHOR]

Published
2024
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