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[Display omitted] Thermal runaway is a hazardous risk, occurring more readily in high-energy–density lithium-ion batteries (LIBs), which leads to a rapid temperature rise and even combustion or explosion when using flammable electrolyte systems. Flame retardants (FRs), such as trimethyl phosphate (TMPa) and triethyl phosphate (TEP), are commonly utilized due to their effective flame suppression, low toxicity, and excellent thermal stability. However, the lack of in-depth understanding of the flame retardancy mechanism and solid electrolyte interphase (SEI) formation process has made the development of functional electrolytes difficult at present. In this study, we clarified the flame retardancy and interfacial reaction mechanisms of low-flammable TMPa localized high-concentration electrolytes (LHCE) using hybrid ab initio and reactive force field (HAIR) schemes. Long-term HAIR simulation reveals that phosphorous radicals produced by the decomposition of TMPa capture carbon radicals, encouraging their polymerization into low-flammable oligomers, while fluorine-containing solvents in the electrolyte capture hydrogen radicals and produce nonflammable hydrofluoric acid (HF). This synergistic flame retardancy mechanism provides essential atomic-level insights for the rational design of high-safety electrolytes in the future. [ABSTRACT FROM AUTHOR]

Ru has recently been considered as a promising alternative of Pt toward hydrogen oxidation reaction (HOR) due to its lower price and similar hydrogen binding energy (HBE) in comparison to Pt. Nevertheless, the catalytic performance of Ru toward HOR is far from the satisfaction of practical application. Herein, it is demonstrated that the modification of Ru multi‐layered nanosheet (MLNS) with Ni can significantly promote the HOR performance. In particular, the HOR performance is strongly related to the Ni location on the surface or in the lattice of Ru MLNS. Experimental and theoretical investigations suggest that Ni in the lattice of Ru MLNS (lattice engineering) optimizes the HBE, while Ni species on the surface (surface engineering) decrease the free energy of water formation, as a result of the significantly enhanced HOR performance. The optimal catalyst, where Ni is located both on the surface and in the lattice, displays superior alkaline HOR performance to commercial Pt/C and Ru/C. The present study not only systematically reveals the significance of Ni modification on Ru toward HOR, but also promotes the fundamental researches on catalyst design for fuel cell reactions and beyond. [ABSTRACT FROM AUTHOR]

The hydrazine oxidation reaction (HzOR) has been considered as a more energy-efficient alternative to the oxygen evolution reaction in water electrolysis. To design efficient electrocatalysts for HzOR, precise engineering of materials is required to increase active sites and build electronic structures. Herein, nitrogen contained face-centered cubic rhodium (N-fcc-Rh) nanosheets are prepared by directly annealing metastable trigonal rhodium oxide precursor in the ammonia atmosphere. Benefiting from the abundant active sites and unique electronic structure, the optimal N-fcc-Rh-300 electrocatalyst achieves an ultra-low working potential of − 81 mV (vs. RHE) at 10 mA cm−2 in 1.0 M KOH/0.5 M N 2 H 4. Density functional theory calculations suggest the N element in the N-fcc-Rh electrocatalyst enables to the reduction of the formation energy of the potential-determining step from *NH 2 NH 2 to *NHNH 2 for the HzOR process. This work reveals a new strategy to prepare advanced metal electrocatalysts for various electrochemical applications. [Display omitted] • Nitrogen contained face-centered cubic rhodium nanosheets. • Excellent HzOR activity with working potential of − 81 mV (vs. RHE) at 10 mA cm−2. • N elements into Rh leads to a shift of the d-band center away from the Fermi level. [ABSTRACT FROM AUTHOR]

This study explores the large-scale involvement of Chinese enterprises in teaching-focused university-industry collaboration (TFUIC), drawing upon the theoretical perspective of resource dependency. Based upon content analysis of Ministry of Education-selected exemplary cases and semi-structured interviews with corporate insiders, the study not only delineates multiple approaches companies take to boost higher education quality, but also unravel the role of economic resources, technological and professional resources in underpinning the implementation of TFUIC. Resources underpinning enterprises’ long-term incentives for participation and the primacy issue between the university sector and industry sector remain challenges to TFUIC. [ABSTRACT FROM AUTHOR]

[Display omitted] • The porous rhodium nanosheets with tunable compressive strain were successfully obtained by directly annealing metastable trigonal rhodium oxide. • The record HzOR performance. • A clear strain effect and catalytic mechanism for alkaline HzOR in single-metal-element systems. Electrocatalytic water decomposition is an essential pathway for large-scale preparation of high-purity hydrogen, while the conventional oxygen evolution reaction (OER) with a kinetically sluggish four-electron process becomes a huge challenge for its further application. Hydrazine oxidation reaction (HzOR) is considered an effective strategy to replace the sluggish OER process, attributed to its lower thermodynamic oxidation potential. Here, porous rhodium nanosheets (Rh-NSs) with tunable lattice strain are successfully obtained by directly annealing metastable trigonal rhodium oxide (Tri-RhO 2) in a hydrogen atmosphere. More importantly, ligand and synergetic effects can be effectively avoided in a single-metal-element system, providing an ideal model electrocatalyst for understanding the correlation between reactivity and lattice strain. The electrochemical results show that the optimal Rh-NSs-300 (the Tri-RhO 2 precursor is annealed at 300 °C) may deliver ultralow working potential (vs. RHE) of −103 mV at the current density of 10 mA cm−2 with a Tafel slope of 15.4 mV dec-1 for HzOR. In addition, the working potential (vs. RHE) of Rh-NSs-300 only drops 35 mV after the 72 h test by chronopotentiometry method at the constant current density of 10 mA cm−2. Density functional theory (DFT) calculations indicate that HzOR can more easily occur on Rh-NSs with tunable compressive strain than pure Rh. [ABSTRACT FROM AUTHOR]

Solid electrolyte interphase (SEI) plays a significant role in enhancing the stability and durability of lithium metal batteries (LMBs) by separating highly reactive lithium metal anode (LMA) from the electrolyte to avoid continuous degradation. However, the underlying reaction mechanism is still far from clear. Herein, a hybrid ab initio and reactive force field (HAIR) method is employed to extend the ab initio molecular dynamics (AIMD) to 1 ns, which provides crystal information about the reaction mechanism of elementary reactions that can explain the components and morphology evolution of SEI formation. Specifically, HAIR simulation confirms the two‐electron (2e–) reduction of ethylene carbonate (EC) by releasing CO and CO2, agreeing with phenomenal experiment observation. As the unsaturated intermediates accumulate, polymerization reactions occur, producing linear polyethylene oxide (PEO), Li2OCO2CH2CH2, Li2OCO2(CH2)4, etc., which regulate the formation of outer organic layer (OOL) that consists of linear polyethylene oxide (PEO), Li2OCO2CH2CH2, Li2OCO2(CH2)4, etc., and the inner inorganic layer (IIL) mainly consists of LiF and Li2O. Simulations at low concentration (LC, 1M) and high concentration (HC, 5M) reveal significantly different reaction pathways when HC electrolyte can significantly promote the formation of homogenous LiF that has been regarded as an important component to facilitate robust SEI. [ABSTRACT FROM AUTHOR]

Proposed interaction mechanism of cellulose, hemicellulose and lignin during the degradative solvent extraction process of biomass. [Display omitted] • The interaction intensity between the mixtures was in the order of HL > CL > CH. • The interaction between HL mixture reduced the yield of residue by 9.26%. • The synergistic effect between CL lowered the yield of aromatic carbon by 3.19%. • The synergy between CH mixture promoted the production of CO 2 by 37.53 mL/g. • The interaction mechanism between the three components was discussed and revealed. The degradative solvent extraction (DSE) method has been recently developed to deoxygenate and upgrade lignocellulosic biomass wastes into high-quality extracts with a variety of value-added applications. Lignocellulosic biomass is mainly composed of cellulose, hemicellulose and lignin, and the interaction of the three components during the DSE process still remains unclear and needs to be elucidated. Therefore, in this study, the synthetic component mixtures (cellulose/hemicellulose (CH), cellulose/lignin (CL) and hemicellulose/lignin (HL)) were firstly prepared with the model compounds (cellulose, hemicellulose and lignin), and the conversion characteristics of the component mixtures and the superposition of individual component during the DSE process under the same operating conditions were compared to reveal the interaction effect between the three components. The extract yields of cellulose, hemicellulose and lignin were 44.16%, 27.4% and 18.25% respectively, indicating that cellulose contributed mostly to the formation of the extract (the target product) compared with hemicellulose and lignin. Significant interactions were observed for cellulose/lignin and hemicellulose/lignin mixtures, while the interaction effect between cellulose and hemicellulose was relatively small. The interaction intensity between cellulose, hemicellulose and lignin was in the order of HL > CL > CH. The interaction between cellulose/lignin and hemicellulose/lignin promoted the thermal degradation of lignin. Specifically, the interaction between the hemicellulose and lignin mixture reduced the yield of residue by 9.26%. The interaction mechanism between the three components was discussed and revealed based on the detailed characterization of the DSE products. The interaction between the three components could facilitate the production of gaseous products (mainly CO 2), indicating that the interaction between the three components significantly promoted the decarboxylation reaction. The interaction between two of the three components all inhibited the aromatization reaction and reduced the aromaticity of the extracts. During the DSE process of cellulose/lignin or hemicellulose/lignin mixtures, the small-molecular free radicals generated by the decomposition of cellulose or hemicellulose could occupy the active sites on lignin fragments, leading to the significant inhibition of the condensation reactions between different lignin fragments. These interactions leaded to the decrease of the extract yields and residue yields during the DSE process of cellulose/lignin or hemicellulose/lignin mixtures. [ABSTRACT FROM AUTHOR]

Ni-based single-atom catalysis (Ni-SAC) has been experimentally reported with superior performance in reducing CO2 to CO. However, due to the ambiguities in its structures, the active sites of Ni-SAC that are responsible for superior performance have not yet been resolved. This work investigates the CO2 reduction reaction (CO2RR) mechanism on Ni-SAC by carrying out quantum mechanics (QM) simulation to consider both solvation effects. After exploring multiple possible combinations of N, S, and C, we distinguish a Ni-SAC site with two C, one S, and one N, representing the best performance. The predicted formation energy is closely consistent with experimental onset potential. Our prediction also suggests further improvement by finely tuning the electronics state of metal sites by changing the SAC support. [ABSTRACT FROM AUTHOR]