Jian Lu

Bis(trifluoromethyl) sulfide (CF3SCF3) is a candidate insulating gas whose atmospheric persistence is poorly constrained: the structure–activity relationship cannot be reliably extrapolated to this perfluorinated species, and the only available theoretical estimate has not yet been tested against experiment. We measured the rate coefficient of its dominant atmospheric loss, reaction with OH, by pulsed laser photolysis–laser-induced fluorescence over 272–328 K at 50 Torr. The reaction is slow and nearly temperature independent, with k1(298 K) = (2.15 ± 0.34) × 10–15 cm3 molecule–1 s–1 and a slight positive trend (apparent Ea = (0.30 ± 0.14) kcal mol–1). No O2 dependence was detectable at 50 Torr. The measured k1 exceeds the theoretical value by approximately an order of magnitude, implying an OH-initiated lifetime of ∼14.7 years and a 100-year GWP of ∼2570, well below that of SF6 (24300), supporting further evaluation of CF3SCF3 as an alternative dielectric gas.

The rapid development of artificial intelligence pushed chip power density to unprecedented levels, making thermal management a critical bottleneck. Although boiling heat transfer offered efficient cooling, conventional enhancement methods exhibited clear limitations: surface modification technologies were approaching their physical and manufacturing limits at micro/nano scales, while external energy fields (such as acoustic, electric, or magnetic fields) increased system complexity and energy consumption. This study addressed the challenge through working fluid innovation and introduced MCLC-10—an environmentally friendly refrigerant characterized by a low global warming potential (≤10) and a nearzero ozone depletion potential. A comprehensive comparison with the industry’s most widely used refrigerant, R1233zd(E), demonstrated MCLC-10’s superior performance advantages. On smooth surfaces, it improved the critical heat flux by 12–14% and enhanced the heat transfer coefficient by 32–36%. Under pressurized conditions with micropinfin enhancement, it achieved a critical heat flux of 96 W·cm⁻² and a peak heat transfer coefficient of 13.56 W·cm⁻²·K⁻¹. In a threedimensional thermosyphon module, MCLC-10 stably sustained a heat dissipation power of 1200 W (thermal resistance: 0.068 K·W⁻¹) and withstood a heat flux of 128 W·cm⁻² (thermal resistance: 0.117 K·W⁻¹), outperforming R1233zd(E) across all key metrics. These results established MCLC-10 as a highperformance, ecofriendly alternative solution for nextgeneration thermal management, providing both experimental evidence and design guidance for cooling high heat flux electronic devices.

The rapid development of artificial intelligence pushed chip power density to unprecedented levels, making thermal management a critical bottleneck. Although boiling heat transfer offered efficient cooling, conventional enhancement methods exhibited clear limitations: surface modification technologies were approaching their physical and manufacturing limits at micro/nano scales, while external energy fields (such as acoustic, electric, or magnetic fields) increased system complexity and energy consumption. This study addressed the challenge through working fluid innovation and introduced MCLC-10—an environmentally friendly refrigerant characterized by a low global warming potential (≤10) and a near‑zero ozone depletion potential. A comprehensive comparison with the industry’s most widely used refrigerant, R1233zd(E), demonstrated MCLC-10’s superior performance advantages. On smooth surfaces, it improved the critical heat flux by 12–14% and enhanced the heat transfer coefficient by 32–36%. Under pressurized conditions with micro‑pin‑fin enhancement, it achieved a critical heat flux of 96 W·cm⁻² and a peak heat transfer coefficient of 13.56 W·cm⁻²·K⁻¹. In a three‑dimensional thermosyphon module, MCLC-10 stably sustained a heat dissipation power of 1200 W (thermal resistance: 0.068 K·W⁻¹) and withstood a heat flux of 128 W·cm⁻² (thermal resistance: 0.117 K·W⁻¹), outperforming R1233zd(E) across all key metrics. These results established MCLC-10 as a high‑performance, eco‑friendly alternative solution for next‑generation thermal management, providing both experimental evidence and design guidance for cooling high heat flux electronic devices.

A Cu-catalyzed stereospecific C–H alkenylation of polyhedral o -carboranes is reported, featuring the use of a practical and inexpensive catalyst and a weak base. The Z - and E -configurations can be memorized through cage C–H activation.

Hydrogen-assisted dehydrochlorination process (HaDHC) is an attractive route for the production of fluorine-containing olefins under relatively mild conditions, so far lacking the highly efficient metal-based catalysts and their design strategy. Here, we report a nano-MgF₂ supported Pd-Ag catalyst with a tunable Pd dispersion, which is optimized by the Pd-Ag alloy degree in the fresh catalyst and subsequently in situ chlorination during the induction period of reaction. After the in situ restructuring process, the resulting Pd-Ag/nano-MgF₂ catalysts with atomically dispersed Pd sites exhibited an excellent catalytic performance for HaDHC of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to 2,3,3,3-tetrafluoropropene (HFO-1234yf), the new-generation refrigerant, with a conversion of ca. 60% and HFO-1234yf selectivity of ca. 82% at 270 °C. Characterization results reveal that the Pd-Ag alloy degree in the fresh catalyst can be facilely tuned by changing the impregnation sequences for bimetallic precursors during catalyst preparation due to different metal-support interactions. Constructing a high Pd-Ag alloy degree offers a high in situ chlorination degree of the catalyst surface to finally get highly isolated Pd sites. Adsorption and computational results demonstrate that the chemisorbed hydrogen species on the single atom Pd sites (Pd-F and Pd-F₃ sites) boost the HFO-1234yf formation, while the spillover hydrogen species derived from the large Pd ensembles (Pd₆, Pd₇, and Pd₈ clusters) contribute to the formation of deep hydrogeneration product, 1,1,1,2-tetrafluoropropane (HFC-254eb).

The hydrogen-assisted dechlorination of 1, 1, 2-trichlorotrifluoroethane (CFC-113) to yield chlorotrifluoroethylene (CTFE) represents an efficient and environmentally alternative to zinc-mediated reductive dechlorination processes. Nevertheless, the industrial implementation of this technology has been constrained by suboptimal catalytic activity and stability in existing catalytic systems. Herein, we developed a high performance trimetallic Pd-Cu-Fe/AC catalyst via wet impregnation method. The optimal Pd-Cu-1.0Fe/AC catalyst exhibited 98.5% CFC-113 conversion, 92.6% CTFE selectivity and over 240 h lifetime under the harsh conditions of T=180 °C, C.T.=10 s and H₂/CFC-113=3/1, which to our knowledge was superior to all of reported catalysts to date. Due to the synergistic interaction of the Pd-Cu-Fe ternary system, the Pd-Cu-1.0Fe/AC catalysts demonstrated excellent catalytic activity, CTFE selectivity and stability. X-ray photoelectron spectroscopy and temperature-programmed reduction results revealed that the addition of Fe could reduce the extent to which Pd (0) was oxidized to Pd (II) and the reduction temperature of Pd (II) during the reaction process. Thermogravimetric analysis and N₂ adsorption/desorption experiments demonstrated that the formation of carbon deposition deactivated the Pd-Cu-Fe/AC catalyst, and the presence of Fe effectively reduced carbon deposition. The DFT calculations corroborated that Fe incorporation augmented the adsorption energy of CFC-113 and H₂ and while attenuating CTFE adsorption, thereby enhancing both catalytic activity and stability of the Pd-Cu-Fe/AC catalyst.

The corrosion of metal substrates is closely associated with the permeability of the corrosive medium in which they are immersed. To enhance the protection of metal materials and improve anti-corrosion performance from an epoxy resin perspective, the diffusion path complexity can be increased and porosity reduced within the epoxy resin coating to effectively block the invasion of corrosive media. Simultaneously, reducing the affinity between the corrosive media and the epoxy resin coating makes it difficult for corrosive substances to adhere. Based on this principle, this study introduces two-dimensional boron nitride nanosheets (BNNS) and fluoropolymers-modified one-dimensional nano-silica (SiO₂) and organic tannic acid as fillers to jointly enhance the protective effect of waterborne epoxy-resin-based composites. Experimental results demonstrate that when the BNNS content is 0.5 wt.%, the 0.5-BNNS/WEP composite coating exhibits superior anti-corrosion performance, achieving an electrochemical impedance of 2.90 × 10⁷ Ω∙cm². Moreover, when BNNS is compounded with fluorinated SiO₂ or fluorinated tannic acid as fillers and incorporated into waterborne epoxy resin, the resulting composite coatings maintain excellent long-term anti-corrosion performance even after 20 days of salt spray testing.

A nickel-catalyzed direct cage B–H poly-chalcogenation of icosahedral carborane clusters, enabled by a variable bidentate 8-aminoquinoline traceless directing group (TDG), has been developed under oxidant-free and weakly basic conditions, resulting in poly-thiolated/selenylated o-carboranes present in boron delivery agents for boron neutron capture therapy (BNCT). The controllable selectivity of removal and retention of these TDGs was achieved through simple substrate structure modification (C2-substitution in o-carboranes). A wide range of disulfides, diselenides, thiophenols and benzeneselenols, as well as o-carborane substrates, are compatible, generating diversely functionalized o-carboranes with tetra- and tri-chalcogen substitution. The current protocol opens new avenues for oxidant- and strong base-free, base-metal-catalyzed regioselective iterative B–H chalcogenation of carboranes via a variable bidentate TDG strategy.