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[Display omitted] • Ni/N 0.8 -CeO 2 was prepared through the capping effect of ionic liquids for the first time. • Ni/N 0.8 -CeO 2 exhibits the highest yields of saturated cycloalkanes using precious metal-free catalysts. • Ni/N 0.8 -CeO 2 excellent performance is due to the synergistic catalysis of OVs and adjacent FLPs of N/Ce3+. • FLPs of N/Ce3+ and Ni nanoparticles produce active hydrogen via a relay catalysis. • FLPs-generated hydrogen and OVs-specific oxygen recognition synergistically enhance catalytic efficiency. The catalytic hydrodeoxygenation (CHDO) of lignin into saturated cycloalkanes not only enhances the efficient utilization of lignin but also reduces reliance on high-density liquid fuels (HDLFs), given the importance of saturated cycloalkanes as key constituents of HDLFs. The main challenge in lignin CHDO towards HDLFs is efficiently removing oxygen-atom while maintaining high selectivity for the desired saturated cycloalkanes. Herein, we report for the first time the fabrication of a Ni/N 0.8- CeO 2 -500 composite with abundant oxygen vacancies (OVs) and adjacent frustrated Lewis pairs (FLPs), achieved through the capping effect of ionic liquids. The FLPs of N/Ce3+ within Ni/N 0.8 -CeO 2 -500, mediated by OVs, not only enhance the dispersion of Ni species but also effectively facilitate the conversion of H 2 into active hydrogen (H*) through relay catalysis involving the Ni species. This integration, combining the oxygen atom-specific recognition of OVs with the adjacent FLPs of N/Ce3+ for the tandem generation of H*, significantly promotes the adsorption/cleavage of C ar/alk −O−C alk bonds, oxygen-atom removal, and hydrogenation of aromatic rings, ultimately catalyzing the one-step production of saturated cycloalkanes. The synergistic catalytic interplay results in a remarkable yield of saturated cycloalkanes (up to 88.2 wt%) during the CHDO of Kraft lignin, representing the highest reported value under similar conditions to date. A combination of diverse characterizations, experimental analyses, and kinetic studies collectively reinforces the notion that in-situ N-doping of CeO 2 increases the electron cloud density around Ce species, forming N-Ceδ+ entities that, at high temperatures, create OVs and adjacent FLPs of N-Ce3+, collectively enhancing lignin CHDO to yield saturated cycloalkanes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel photic responsive Janus nanoparticles were prepared, which rapidly demulsified under UV light. • Reaction mechanism was verified by an isotope calibration test. • The excellent yield (97.89 %) of soybean oil-based biodiesel was realized by this Pickering emulsion. • Catalyst can be directly reused without any recovery operation. • This catalytic system promotes the industrial mass production of biodiesel. Smart Janus nanoparticles have been extensively utilized as interfacial catalysts for various organic transformations. The solid basic ionic polymer catalysts were prepared by introducing basic ionic liquid (F-DABCO) and innovative photic responsive monomer (SPA) on the surface of Janus SiO 2 nanoparticles using reversible addition-fragmentation chain transfer. The as-prepared Pickering emulsion is employed in the transesterification reaction between soybean oil and methanol to synthesize biodiesel and achieve demulsification/emulsification switches by alternating exposure between ultraviolet and visible light. The transesterification reaction mechanism was verified by an isotope calibration test. The effect of the parameter showed that at optimum values of 62.9 °C in 6 h with a 1:11.2 oil-to-methanol molar ratio and catalyst amount of 5.1 wt%, the yield of biodiesel can be arrived at 97.9 %. Finally, the catalysts demonstrated the capacity for multiple reuses, indicating that functional Janus nanoparticles can be used as a good catalyst for the Pickering oil/methanol interface for efficient production of biodiesel-Introduction. [ABSTRACT FROM AUTHOR]

Directionally converting waste frying oil (WFO) to biodiesel is not only a crucial strategy for its clean and efficient utilization, but also a promising alternative for the large-scale substitution of petroleum-based fuels. However, the challenge of reducing mass transfer resistance between the alcohol/oil bi-liquid phases remains a major obstacle in the industrialization of WFO-based biodiesel (WFOBB). Additionally, both rapid emulsification and efficient demulsification still present bottlenecks that need to be addressed in emulsion reaction. Herein, the present study successfully demonstrates the fabrication of a novel Pickering interfacial catalyst with immobilized Brønsted-Lewis di-acid functionalized ionic liquids and photosensitizer (P(5[DVB]-[SP]-[ILs-2FeCl 3 ])@SiO 2 @Fe 3 O 4) through layer-by-layer self-assembly. This novel Pickering interfacial catalyst efficiently constructed an intelligent magneto-optical dual stimuli-responsive Pickering emulsion. The intelligent Pickering emulsion enables precise control over amphiphilic interfacial catalyst using Vis-light regulation, thereby significantly enhancing mass transfer in the biphasic methanol-WFO system while providing an optimal hydrophobic micro-environment for highly efficient WFOBB production. The intelligent Pickering catalyst exhibits exceptional catalytic performance in achieving a 92.4% yield of WFOBB, which is currently the highest reported value under similar conditions. Furthermore, the efficient demulsification and separation of this Pickering interfacial catalyst could be achieved through the synergistic effect of UV-irradiation-induced hydrophilicity and its magnetic property. These findings present a new avenue for advancing the development of WFOBB technologies, while also offering promising prospects for industrial applications of Pickering emulsion systems. [Display omitted] • The fabrication of a novel Pickering interfacial catalyst was achieved. • An intelligent magneto-optical dual responsive Pickering emulsion was developed. • This Pickering emulsion addressed the challenge of reducing mass transfer resistance. • This Pickering emulsion resolved the rapid emulsification and efficient demulsification. • The utilization of this Pickering emulsion facilitated an excellent yield for WFOBB. [ABSTRACT FROM AUTHOR]

Vigorous advocacy for the promising strategy on biodiesel replacing petrodiesel can effectively alleviate the dual pressure of energy deficiency and environmental pollution. Nevertheless, the difficulty of lowering larger mass transfer resistance between two-phases of alcohol/oil is a stumbling block in the biodiesel production. Furthermore, the high catalytic efficiency of the most commonly used solid bases for biodiesel production is weakened due to the saponification reaction caused by fatty acids in feedstock. Addressing these two issues has emerged as a pressing concern for achieving efficient biodiesel production. Herein, a polyacrylonitrile fiber (PANF) with light-driven intelligent reversible and switchable wettability, i.e. , PANF-NH 2 @RAFT@SPA&[AD][OH] featuring Brønsted-Lewis di-base sites and photoresponsiveness, was successfully fabricated through reversible addition fragmentation chain transfer strategy. Physicochemical properties of the resulting fibers were characterized by FT-IR, XRD, NMR, TGA, SEM, TEM, XPS, WCA, and UV–Vis. The effect of methanol-to-oil molar ratio, reaction temperature, reaction time and catalyst feed on biodiesel production was also investigated. Under optimal conditions, a maximum soybean oil conversion of 100% was achieved with a corresponding biodiesel yield of 98.97%, which is an exceptional and unprecedented result. These impressive results can be ascribed to the microenvironment facilitated by the novel intelligent amphiphilic PANF, which effectively enhances mass transfer in a biphasic medium phase of methanol/oil. The microenvironment could be rapidly changed via Vis-regulating PANF hydrophobicity, followed by observably promoting catalyst recovery and phase separation between resultant biodiesel and excess methanol. This catalyst shows no obvious changes in terms of the catalytic activity and selectivity after successive reuses of up to 10 cycles. The economic feasibility and negligible environmental impact of this methodology, coupled with its expediency and efficacy for conducting experiments at kilogram-scale quantities, render it highly compatible with large-scale industrial production of biodiesel. [Display omitted] • PANF with light-driven intelligent reversible and switchable wettability was successfully fabricated. • Novel intelligent switchable microenvironment effectively enhances mass transfer and phase separation. • The high anti-saponification was connected to a strong dispersion force. • This protocol was convenient and effective for kilogram-scale experiments. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ionic liquid was loaded on polyacrylonitrile fiber by RAFT polymerization. • The amphiphilic microenvironment was formed during catalytic process. • Fiber supported polymeric catalyst was successfully to produce biodiesel. Efficient and green production is extremely essential to the development of society and environment, and supported polymeric ionic liquids as heterogeneous catalysts are the current research hotspot for chemists. In this study, imidazolium ionic liquids were supported on modified polyacrylonitrile fiber (PANF) by reversible addition fragmentation chain transfer (RAFT) polymerization, and a series of fiber-supported basic catalysts (PANF@VIm -n X) were obtained by ion exchange with different anions. The modified fibers were characterized by FT-IR, XRD, TGA, SEM, 13C CP-MAS NMR and ICP-MS. The results show that the modified fibers are successful and the catalysts have sufficient active sites and mechanical strength to meet the application requirements. Several supported poly(ionic liquid)s catalysts were used to promote the transesterification of methanol and soybean oil to produce biodiesel. The effects of ionic liquids with different structures on the reaction yield were sufficiently investigated. The anions of ionic liquids and the length of hydrophobic alkyl chains have synergistic effects on the catalytic performance of the catalyst. The fiber catalyst (PANF@VIm -8 OMe) with 8 carbon alkyl chains and OMe anion showed the optimal catalytic efficiency. The yield of biodiesel was as high as 95.4 % within 6 h with a catalyst dosage of 4 wt% and a methanol to oil ratio of 30:1 at 60 ℃. In addition, the fiber catalyst had excellent stability and durability, which could be recycled more than 6 times. Finally, the fiber could be twined on the stirring impeller of the reactor, indicating its potential industrial application prospect. [ABSTRACT FROM AUTHOR]

Efficient and selective conversion of lignin into aromatic monomers (AMs) is extremely essential for the economic feasibility of biorefinery. Nevertheless, the high catalytic efficiency of solid acid catalysts (SACs) for lignin conversion into AMs is remarkably weakened by the present of water produced during the above reaction leading to the deactivation and leaching of acidic sites. More importantly, the directional preparation of SACs with well-defined mesopores, hydrophobicity, and Brønsted-Lewis acidic sites still remains a grand challenge for heterogeneous catalyst development. To overcome these limitations, a desired multifunctional poly(ionic liquid)s (MFPILs) with above-mentioned structural and chemical properties were successfully constructed by an innovative synergistic regulation-induced co -polymerization. Then, MFPILs exhibit more excellent catalytic performance than poly(ionic liquid)s containing Lewis acidic site, Brønsted acidic site, or hydrophilicity alone with 47.9% conversion of lignin and 24.6 wt% yield of AMs, which is the excellent yield reported for the catalytic hydroconversion of lignin using non-precious-metal catalysts. The high catalytic performance of MFPILs for the production of lignin-derived AMs are attributed to the synergistic co-catalysis of the hydrophobic micro-environment, Brønsted-Lewis acidic sites, and mesoporous confinement, which was further confirmed by water contact angle, H 2 temperature programmed desorption, and adsorption experiment. Further, MFPILs featuring magnetic recovery properties can be recycled for at least 10 run times without a significant lower catalytic activity. The work not only sheds some light on fabricating the novel SACs, but also develops a powerful new strategy to produce lignin-derived AMs. [Display omitted] • MFPILs were prepared innovatively for the first time. • MFPILs exhibit the highest yield of AMs with precious metal-free catalysts. • The excellent performance of MFPILs is attributed to the synergistic catalysis. • The synergistic co-catalysis is confirmed by various analytical methods in detail. [ABSTRACT FROM AUTHOR]

[Display omitted] • Photo-responsive magnetic interfacial catalysts with ionic moiety were prepared. • Catalysts could stable soybean oil-in-methanol emulsions for up to 24 h. • Recovery of catalyst from emulsion is within 5 min by double responsiveness. • Catalysts could be reused in efficient preparation of biodiesel for 6 times. The prime purpose of this work is to prepare a novel kind of Pickering interfacial solid catalysts for biodiesel production to meet the requirements of highly efficiency and environmental benign. To achieve this goal, the core–shell P[xSPA-yDABCO]@SiO 2 @Fe 3 O 4 composite materials with a shell of photo-responsive and base catalytic sites were manufactured by means of layer-by-layer fabrication method. The modified materials, entirely characterized by transmission electron microscopy (TEM), scanning electron microscope (SEM), Fourier transform infrared (FT-IR) spectra, X-ray powder diffraction (XRD) and magnetization versus magnetic (VSM) techniques, demonstrated sufficient catalytic active sites and photo-responsive sites. Among all the so-prepared catalysts, P[3SPA-2DABCO]@SiO 2 @Fe 3 O 4 performs extremely well and can stabilize soybean oil-in-methanol Pickering emulsion for 24 h, achieving a biodiesel yield up to 98.2% at a catalyst dosage of 5 wt% after the reaction time of 5 h at 60 °C. Furthermore, the double responsive solid catalyst can be readily separated from the mixture of reaction by an external magnet and UV irradiation, and still presented superior catalytic activity after 6 cycles. [ABSTRACT FROM AUTHOR]

Herein, spiropyran (SPA) and 1-vinyl-3-ethylimidazole were firstly grafted as conjugated polymer onto the Polyacrylonitrile fiber (PANF) by reversible addition fragmentation chain transfer (RAFT), and then their imidazole cation were used as exchanger to prepare an intelligent photo-responsive catalyst loaded with intact Keggin hydrogen phosphotungstate (H x PW 12 O 40 (3−x) -), which were fully characterized by FT-IR, XPS, SEM, TGA and ICP. The obtained catalysts could efficiently promote the aqueous oxidation of benzyl alcohol in presence of H 2 O 2. The reversible light-responsive property of SPA on fiber renders its hydrophobic microenvironment which is propitious to adsorb organic starting substrates in the reaction process, while the increasing hydrophilicity, derived from the ring opening of SPA by ultraviolet light, can desorb the product completely from the fiber. The whole catalytic process, including reaction stage and work-up stage, does not need any volatile organic solvent and the catalysts could be recycled for 10 times without any significantly loss of activity. Finally, the fiber could be further twinned on the impeller of mechanical stirrer, demonstrating the readily scale-up production potential. [Display omitted] • Using RAFT, UV responsive fiber was prepared to catalyze the oxidation reaction. • Hydrophobic SPA based fiber is favorable for adsorption of substrate and reaction. • Ring opening of SPA by ultraviolet light can desorb product from the fiber. • Whole catalytic process is absolutely solvent-free. • Switchable fiber could be recycled for 10 times. [ABSTRACT FROM AUTHOR]

Carbon-based supercapacitors with outstanding electrochemical performances are strongly desired for the development of portable and wearable electronics. From the free radical engineering point of view, this study innovatively developed carbon/carbon gradient-structured microspheres (CCGMs) by the strategy of "third-order graduation polymerization" and "dynamic radical oxidation". Compared to conventional hybrid materials, for the first time, the gradient structure is proved to be extremely beneficial for improving the capacitive performance. Benefiting its gradient-structured advantages, the CCGMs exhibited "three-ultrahigh" performance with gravimetric, volumetric, and areal capacitances of 408.23 F g−1, 741.11 F cm−3, and 4390 μF cm−2, respectively. In addition, the assembled all-solids-state micro-supercapacitors delivered superior volumetric and areal specific capacitances (7.704 F cm−3 and 9.245 mF cm−2 at 5 μA cm−2), excellent life-span (100% after 12000 cycles), excellent volumetric and areal energy densities (1070 mWh cm−3 and 1284 μWh cm−2). This work paves a new way to develop unique carbon composites for high‐performance energy storage devices. • A third-order graduation polymerization method was developed. • The dynamic radical oxidation method was used for ultramicroporous-confined defects. • The gradient structure could improve the "three-ultrahigh" performance of carbons. [ABSTRACT FROM AUTHOR]