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Evolution of the Pd0/PdO phase change on Pd-MCM-41 catalyst for efficient production of furfural from the fast pyrolysis of cellulose
(Elsevier, 2024-09-15) Wang, JW; Zhou, QQ; Gu, JX; Yang, S; Gu, QF; De Girolamo, A; Zhang, L
Furfural (C5H4O2) is a high-value platform chemical that is traditionally derived from the solvolysis of hemicellulose. However, its production from pyrolysis is far from satisfactory. In particular, the abundant cellulose within lignocellulosic biomass has yet to be successfully upgraded into furfural. Consequently, the overall yield of furfural from a lignocellulosic biomass is extremely low. Herein, we report a facile heterogeneous catalyst prepared from a simple impregnation of palladium (Pd) onto MCM-41 mesoporous silica. The catalyst demonstrated a remarkably high selectivity of ∼58.5% and yield of ∼32.5 wt% for furfural from the fast pyrolysis of wet cellulose. It was also confirmed to reach a selectivity of 65.4% and yield of 44.5 wt% for furfural from wet xylan, as well as a furfural yield of 23.9 wt% from wet sugarcane bagasse. All these values are superior to the literature reports. Through advanced characterisation including in-situ synchrotron high-temperature XRD and DRIFTS measurement, the loading of Pd in a tiny quantity of 1 mol% was confirmed to be sufficient in enhancing the surface hydrophilicity of the MCM-41 support, promoting the adsorption of reactants especially the formaldehyde group (HCHO), as well as the desorption of the target product furfural. In addition, Pd oxide (i.e., Pd2+O) was confirmed to be the catalytic active site. However, it was partly reduced into metallic Pd0 during the cellulose pyrolysis, due to the preferred reduction by adsorbed formaldehyde group and other reductants including H2 and CO in the vicinity of the PdO sites on the Pd-O-Si interface. Nevertheless, the catalyst was proven to retain the memory of its initial state after combustive regeneration in air, having oxidation state of Pd, particle size, and dispersion degree being reversed to its original construction. Accordingly, its activity remained stable upon cyclic testing. All these results demonstrate a high practical viability of this heterogenous catalyst for the valorisation of cellulose-rich biomass, an otherwise abundant crop waste across the world. © 2024 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ ).
Correction to “Impurity tolerance of unsaturated Ni-N‑C active sites for practical electrochemical CO2 reduction"
(American Chemical Society, 2024-11-26) Leverett, J; Yuwono, JA; Kumar, P; Tran-Phu, T; Qu, JT; Cairney, JM; Wang, Xi; Simonov, AN; Hocking, RK; Johannessen, B; Dai, L; Daiyan, R; Amal, R
The authors regret that the affiliation recorded for Bernt Johannessen is incomplete. The full affiliation should be “Australian Synchrotron, ANSTO, Clayton VIC 3168, Australia”. The authors would like to apologize for any inconvenience caused. The correction does not in any way affect the results or conclusions of the publication.
Synergistic effect of Co‐Mo pinning in lay‐structured oxide cathode for enhancing stability toward potassium‐Iion batteries
(Wiley, 2024-03-10) Han, WZ; Gao, XW; Song, YY; Wang, XC; Gao, GP; Chen, H; Gu, QF; Luo, WB
Owing to the high economic efficiency and energy density potential, manganese‐based layer‐structured oxides have attracted great interests as cathode materials for potassium ion batteries. In order to alleviate the continuous phase transition and K+ re‐embedding from Jahn‐Teller distortion, the [Mn‐Co‐Mo]O6 octahedra are introduced into P3‐K0.45MnO2 herein to optimize the local electron structure. Based on the experimental and computational results, the octahedral center metal molybdenum in [MoO6] octahedra proposes a smaller ionic radius and higher oxidation state to induce second‐order JTE (pseudo‐JTE) distortion in the adjacent [MnO6] octahedra. This distortion compresses the [MnO6] octahedra along the c‐axis, leading to an increased interlayer spacing in the K+ layer. Meanwhile, the Mn3+/Mn4+ is balanced by [CoO6] octahedra and the K+ diffusion pathway is optimized as well. The proposed P3‐K0.45Mn0.9Co0.05Mo0.05O2 cathode material shows an enhanced cycling stability and rate performance. It demonstrates a high capacity of 80.2 mAh g−1 at 100 mAh g−1 and 77.3 mAh g−1 at 500 mAh g−1. Furthermore, it showcases a 2000 cycles stability with a 59.6% capacity retention. This work presents a promising solution to the challenges faced by manganese‐based layered oxide cathodes and offers a deep mechanism understanding and improved electrochemical performance. © 1999-2025 John Wiley & Sons, Inc or related companies.
Flexible wearable energy storage devices: materials, structures, and applications
(Wiley, 2024-01-08) Zhang, Q; Gao, XW; Liu, X; Mu, JJ; Gu, QF; Liu, ZM; Luo, WB
Wearable electronics are expected to be light, durable, flexible, and comfortable. Many fibrous, planar, and tridimensional structures have been designed to realize flexible devices that can sustain geometrical deformations, such as bending, twisting, folding, and stretching normally under the premise of relatively good electrochemical performance and mechanical stability. As a flexible electrode for batteries or other devices, it possesses favorable mechanical strength and large specific capacity and preserves efficient ionic and electronic conductivity with a certain shape, structure, and function. To fulfill flexible energy‐storage devices, much effort has been devoted to the design of structures and materials with mechanical characteristics. This review attempts to critically review the state of the art with respect to materials of electrodes and electrolyte, the device structure, and the corresponding fabrication techniques as well as applications of the flexible energy storage devices. Finally, the limitations of materials and preparation methods, the functions, and the working conditions of devices in the future were discussed and presented. © 2024 The Authors. Battery Energy published by Xijing University and John Wiley & Sons Australia, Ltd.
Long-range A-site cation disorder in NaA(MO4)2 (M = Mo, W) double scheelite oxides
(Elsevier, 2023-05) Mullens, BG; Nicholas, MK; Marlton, FP; Brand, HEA; Gu, QF; Maynard-Casely, HE; Kennedy, BJ
Synchrotron X-ray and neutron powder diffraction methods have been used to obtain accurate long-range average structures of some double scheelite compounds of the type NaA(BO4)2 (A = La, Pr, Nd, Sm, Lu, and Bi; B = Mo, W) at room temperature. Phase pure samples were synthesized using standard solid-state methods. Rietveld refinements using combined synchrotron X-ray diffraction (SXRD) and neutron diffraction (NPD) revealed a random distribution of the Na and A-type cations regardless of the presence of 6s2 lone pairs (such as Bi3+) and the difference in oxidation states and ionic radii between the cations. The NaA(BO4)2 (A = La, Pr, Nd, Sm, Lu, and Bi) series displayed linear trends in lattice parameters and AO8 polyhedra volume with the ionic radius of the A-type cation for the lanthanoids, but a deviation from the trend was observed for A = Bi3+. The NaBi(BO4)2 structure has a smaller than expected unit cell volume than based on extrapolation from the corresponding NaLn(BO4)2 series, possibly due to short-range ordering of the 6s2 lone pair electrons. © 2023 Elsevier Inc.

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