Suppressing ion migration in metal halide perovskite via interstitial doping with a trace amount of multivalent cationsNature Materials，Pub Date:2022-11-17,DOI:10.1038/s41563-022-01390-3Yepin Zhao, Ilhan Yavuz, Minhuan Wang, Marc H. Weber, Mingjie Xu, Joo-Hong Lee, Shaun Tan, Tianyi Huang, Dong Meng, Rui Wang, Jingjing Xue, Sung-Joon Lee, Sang-Hoon Bae, Anni Zhang, Seung-Gu Choi, Yanfeng Yin, Jin Liu, Tae-Hee Han, Yantao Shi, Hongru Ma, Wenxin Yang, Qiyu Xing, Yifan Zhou, Pengju Shi, …Yang Yang Cations with suitable sizes to occupy an interstitial site of perovskite crystals have been widely used to inhibit ion migration and promote the performance and stability of perovskite optoelectronics. However, such interstitial doping inevitably leads to lattice microstrain that impairs the long-range ordering and stability of the crystals, causing a sacrificial trade-off. Here, we unravel the evident influence of the valence states of the interstitial cations on their efficacy to suppress the ion migration. Incorporation of a trivalent neodymium cation (Nd3+) effectively mitigates the ion migration in the perovskite lattice with a reduced dosage (0.08%) compared to a widely used monovalent cation dopant (Na+, 0.45%). The photovoltaic performances and operational stability of the prototypical perovskite solar cells are enhanced with a trace amount of Nd3+doping while minimizing the sacrificial trade-off.https://www.nature.com/articles/s41563-022-01390-3
Covalent organic framework membranes for efficient separation of monovalent cationsNature Communications，Pub Date:2022-11-19,DOI:10.1038/s41467-022-34849-7Hongjian Wang, Yeming Zhai, Yang Li, Yu Cao, Benbing Shi, Runlai Li, Zingting Zhu, Haifei Jiang, Zheyuan Guo, Meidi Wang, Long Chen, Yawei Liu, Kai-Ge Zhou, Fusheng Pan, Zhongyi Jiang Covalent organic frameworks (COF), with rigid, highly ordered and tunable structures, can actively manipulate the synergy of entropic selectivity and enthalpic selectivity, holding great potential as next-generation membrane materials for ion separations. Here, we demonstrated the efficient separation of monovalent cations by COF membrane. The channels of COF membrane are decorated with three different kinds of acid groups. A concept of confined cascade separation was proposed to elucidate the separation process. The channels of COF membrane comprised two kinds of domains, acid-domains and acid-free-domains. The acid-domains serve as confined stages, rendering high selectivity, while the acid-free-domains preserve the pristine channel size, rendering high permeation flux. A set of descriptors of stage properties were designed to elucidate their effect on selective ion transport behavior. The resulting COF membrane acquired high ion separation performances, with an actual selectivity of 4.2–4.7 for K+/Li+binary mixtures and an ideal selectivity of ~13.7 for K+/Li+.https://www.nature.com/articles/s41467-022-34849-7
Precise tuning of interlayer electronic coupling in layered conductive metal-organic frameworksNature Communications，Pub Date:2022-11-24,DOI:10.1038/s41467-022-34820-6Yang Lu, Yingying Zhang, Chi-Yuan Yang, Sergio Revuelta, Haoyuan Qi, Chuanhui Huang, Wenlong Jin, Zichao Li, Victor Vega-Mayoral, Yannan Liu, Xing Huang, Darius Pohl, Miroslav Položij, Shengqiang Zhou, Enrique Cánovas, Thomas Heine, Simone Fabiano, Xinliang Feng, Renhao DongTwo-dimensional conjugated metal-organic frameworks (2D c-MOFs) have attracted increasing interests for (opto)-electronics and spintronics. They generally consist of van der Waals stacked layers and exhibit layer-depended electronic properties. While considerable efforts have been made to regulate the charge transport within a layer, precise control of electronic coupling between layers has not yet been achieved. Herein, we report a strategy to precisely tune interlayer charge transport in 2D c-MOFs via side-chain induced control of the layer spacing. We design hexaiminotriindole ligands allowing programmed functionalization with tailored alkyl chains (HATI_CX, X = 1,3,4; X refers to the carbon numbers of the alkyl chains) for the synthesis of semiconducting Ni3(HATI_CX)2. The layer spacing of these MOFs can be precisely varied from 3.40 to 3.70 Å, leading to widened band gap, suppressed carrier mobilities, and significant improvement of the Seebeck coefficient. With this demonstration, we further achieve a record-high thermoelectric power factor of 68 ± 3 nW m−1 K−2in Ni3(HATI_C3)2, superior to the reported holes-dominated MOFs.https://www.nature.com/articles/s41467-022-34820-6
Engineering Single-Atom Sites into Pore-Confined Nanospaces of Porphyrinic Metal–Organic Frameworks for the Highly Efficient Photocatalytic Hydrogen Evolution ReactionJournal of the American Chemical Society，Pub Date:2022-11-25, DOI:10.1021/jacs.2c10801Qijie Mo, Li Zhang, Sihong Li, Haili Song, Yanan Fan, Cheng-Yong SuAs a type of heterogeneous catalyst expected for the maximum atom efficiency, a series of single-atom catalysts (SACs) containing spatially isolated metal single atoms (M-SAs) have been successfully prepared by confining M-SAs in the pore-nanospaces of porphyrinic metal–organic frameworks (MOFs). The prepared MOF composites of M-SAs@Pd-PCN-222-NH2(M = Pt, Ir, Au, and Ru) display exceptionally high and persistent efficiency in the photocatalytic hydrogen evolution reaction with a turnover number (TON) of up to 21713 in 32 h and a beginning/lasting turnover frequency (TOF) larger than 1200/600 h–1based on M-SAs under visible light irradiation (λ ≥ 420 nm). The photo-/electrochemical property studies and density functional theory calculations disclose that the close proximity of the catalytically active Pt-SAs to the Pd–porphyrin photosensitizers with the confinement and stabilization effect by chemical binding could accelerate electron–hole separation and charge transfer in pore-nanospaces, thus promoting the catalytic H2evolution reaction with lasting effectiveness.https://pubs.acs.org/doi/abs/10.1021/jacs.2c10801
Reticular Chemistry with Art: A Case Study of Olympic Rings-Inspired Metal–Organic FrameworksJournal of the American Chemical Society，Pub Date:2022-11-23, DOI:10.1021/jacs.2c09832Jincheng Si, Hai-Lun Xia, Kang Zhou, Jingbai Li, Kai Xing，Jiafeng Miao, Jian Zhang, Hao Wang, Lu-Lu Qu, Xiao-Yuan Liu, Jing LiHerein, we demonstrate the successful utilization of reticular chemistry as an excellent designing strategy for the deliberate construction of a zirconium–tetracarboxylate metal–organic framework (MOF) inspired by the Olympic rings. HIAM-4017, with an unprecedented (4,8)-c underlying net topology termedjcs, was developed via insightful reconstruction of the rings and judicious design of a nonsymmetric organic linker. HIAM-4017 exhibits high porosity and excellent chemical and thermal stability. Furthermore, excited-state intramolecular proton transfer (ESIPT) was achieved in an isoreticular MOF, HIAM-4018, with a large Stokes shift of 155 nm as a result of introducing the hydroxyl group to the linker skeleton to induce OH···N interactions. Such interactions were analyzed thoroughly by employing the time-dependent density functional theory (TD-DFT). Because of their good thermal and chemical stability, and strong luminescence, nanosized HIAM-4017 and HIAM-4018 were fabricated and used for Cr2O72–detection. Both MOFs demonstrate excellent sensitivity and selectivity. This work represents a neat example of building structure- and property-specific MOFs guided by reticular chemistry.https://pubs.acs.org/doi/abs/10.1021/jacs.2c09832
Surface-Clean Au25 Nanoclusters in Modulated Microenvironment Enabled by Metal–Organic Frameworks for Enhanced CatalysisJournal of the American Chemical Society，Pub Date:2022-11-21, DOI:10.1021/jacs.2c09136He Wang, Xiyuan Liu, Weijie Yang, Guangyang Mao, Zheng Meng, Zhikun Wu, Hai-Long Jiang Metal nanoclusters (NCs) with atomically precise structures have sparked interest in catalysis. Unfortunately, their high aggregation tendency and the spatial resistance of surface ligands pose significant challenges. Herein, Au25NCs are encapsulated into isoreticular metal–organic frameworks (MOFs), namely UiO-66-X (X = H, NH2, OH, and NO2), followed by the removal of surface ligands on Au25NCs. The resulting surface-clean Au25NCs, protected by the MOF spatial confinement, exhibit much superior activity and stability with respect to pristine Au25NCs in the oxidative esterification of furfural. Remarkably, experimental and theoretical results jointly demonstrate that diverse functional groups on UiO-66-X modulate the Au25electronic state, giving rise to the discriminated substrate adsorption energy of Au25@UiO-66-X. As a result, the high electron density and suitable substrate adsorption ability dominate the activity trend: Au25@UiO-66-NH2> Au25@UiO-66-OH > Au25@UiO-66 > Au25@UiO-66-NO2. This work develops a new strategy for the stabilization of surface-clean metal NCs in pore wall-engineered MOFs for enhanced catalysis.https://pubs.acs.org/doi/abs/10.1021/jacs.2c09136
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