To address the limitations of traditional synthesis methods for gold nanostructures, which rely on high temperatures, toxic reagents, and harsh conditions, this study proposes an eco-friendly strategy for synthesizing gold spikelet nanoflowers using poly(ionic liquid) (PIL) as a structure-directing agent. By employing HAuCl4 as the precursor and ascorbic acid (AA) as the reducing agent, hierarchical Au spikelet nanoflowers with tertiary structure were successfully prepared via a one-pot method in a 60 °C water bath. Systematic investigation of the influencing factors revealed that temperature, AA concentration, and PIL concentration collectively determine the product morphology, with PIL concentration exerting the most significant influence on both the morphology and hierarchical structure of the Au nanoflowers. Using Rhodamine 6G (R6G) as a molecular probe, the resulting substrate exhibited exceptional surface-enhanced Raman scattering (SERS) sensitivity, achieving a detection limit of 10− 12 M for R6G, which surpasses the performance of most reported Au/Ag-based materials, and demonstrates high reproducibility (< 2

Solar-driven photothermal CO2 reduction into multicarbon (C2 +) products represents a promising yet challenging route for sustainable fuel production. A key obstacle remains the inefficient C-C coupling due to poor CO2 activation and limited charge utilization, especially under full-spectrum light. Herein, we propose a heterojunction photocatalyst that synergistically integrates the topological insulator Bi2Te3 with oxygen-doped TiO2-X to address these challenges. The metallic nature of Bi2Te3 enables broad-spectrum photon harvesting from UV to near-infrared and generates substantial photothermal heat, while the oxygen vacancies in TiO2-X create an asymmetric electronic environment that promotes CO2 adsorption, bending, and activation. The built-in electric field formed at the heterointerface drives efficient electron transfer from Bi2Te3 to TiO2-X, which suppresses charge recombination and ensures a prolonged electron supply for multistep reduction reactions. Under full-spectrum irradiation without external heating, the optimized Bi2Te3/TiO2-X catalyst achieves a remarkable C2 + production rate of 15.08 mu mol g-1 h-1 with selectivity toward C2H4 and C2H6. Combined photoelectronic measurements and theoretical analyses confirm that the synergistic photothermal-photocatalytic effect and tailored charge dynamics collectively lower the energy barrier for C-C coupling. This work offers a strategic material design leveraging topological insulators and defect engineering for efficient CO2-to-C2 + conversion.

A simple, one-step, room-temperature, aqueous-phase strategy is presented for synthesizing hierarchical bimetallic nanostructures with superior catalytic properties. This approach utilizes a poly(ionic liquid) (PIL), specifically poly(1-vinyl-3-ethylimidazolium bromide) (PVEIB), which functions as an all-in-one reaction medium and structure-directing agent in aqueous solution at ambient temperature, enabling the facile preparation of well-defined AuPd nanosnowflakes (NSFs). The resulting morphology exhibits a unique four-level hierarchy assembled from nanoparticle building blocks. Systematic investigation identifies both PVEIB concentration and Au/Pd precursor ratio as critical parameters governing this hierarchical growth. Benefiting from its open architecture and the synergistic electronic interaction between Au and Pd, AuPd NSFs-1 delivers exceptional performance: it achieves high activity and selectivity (100% conversion, 100% selectivity) in the selective hydrogenation of p-nitrostyrene to p-nitrophenylethane, and maintains robust stability over five catalytic cycles. This PIL-mediated aqueous synthesis thus provides a versatile and sustainable platform for the design of advanced multimetallic nanomaterials for catalytic and related applications.

Selective hydrogenation serves as a pivotal reaction in fine chemical industry, which requires the precise reduction of specific functional groups and thus imposes stringent requirements on corresponding catalysts. Developing a facile and green strategy for the fabrication of high-selectivity catalysts is urgently demanded and remains a formidable technical challenge. Here, a simple ionic liquid-directed route is developed for the fabrication of thorny palladium nanoparticles (Pd NPs) at room temperature in aqueous solution. The synthesis of thorny Pd NPs was achieved at ambient temperature, utilizing Na2PdCl4 as the metal precursor, ascorbic acid as the reducing agent, and the ionic liquid [C4mim]Cl as an eco-friendly reaction medium, which directed the anisotropic growth of Pd nanostructures. To implement this protocol, water-soluble Na2PdCl4 is used as the initial raw materials, ascorbic acid as the reducing agent, and a common ionic liquid 1-butyl-3-methylimidazo-lium chloride ([C4mim]Cl) is applied to guide the growth and formation of thorny Pd NPs, vividly demonstrating the green and cost-saving features. The various factors affecting the shapes and sizes of products are researched. The results demonstrate that [C4mim]Cl is crucial to the formation of thorny Pd NPs. The thorny Pd NPs possess uniform morphology, lots of sharp thorns, high specific surface area and exhibit outstanding catalytic activity, selectivity and durability for nitrobenzene hydrogenation having 100% conversion and 96% selectivity to aniline within 45 min (25 degrees C, 1 atm H2). The thorny Pd NPs are also expected to have potential application value in other fields such as nanodevices, electrocatalysis and sensing.

Bismuth oxychalcogenides (Bi2O2X; X = S, Se, Te) hold promise as novel candidates for room temperature ultrasensitive optoelectronic devices. However, the relaxation of devices caused by the thermoelectric effect severely limits their application in ultrafast photodetectors. In this study, a vertical p-GaN/Bi2O2Te/Bi2Te3 heterojunction is fabricated using a simplified chemical vapor deposition technique, successfully achieving modulation of the response performance of the heterojunction device with the assistance of a weak electric field. Under 254 nm irradiation with a bias voltage of -0.1 V, the device exhibits a responsivity of 671.9 mA/W and a specific detectivity of 9.099 & times; 1010 Jones, as well as a rise time of 1.83 ms and a decay time of 1.76 ms. Particularly noteworthy is the ultrafast response exhibited by the device in both the UV and NIR bands, with tau rise and tau decay of 74.2 & micro;s and 162.0 & micro;s under 405 nm irradiation, and 126 & micro;s and 130 & micro;s under 980 nm irradiation, respectively. Furthermore, the p-GaN/Bi2O2Te/Bi2Te3 device exhibits excellent stability and outstanding imaging capability under broadband irradiation. This significant research lays the groundwork for future applications and the development of novel broadband multifunctional photodetectors.

The anisotropic bimetal nanoflowers have demonstrated exceptional performance across various fields and gained significant attention, but their green one-pot preparation still remains a technical challenge. Here, a pioneering effort is represented for the synthesis of nanorod-built AuPt nanoflowers (NFs) in a deep eutectic solvent (DES) composed of choline chloride (ChCl) and urea with H2PtCl6 and HAuCl4 as metal precursors and ascorbic acid as the reducing agent, demonstrating the environmentally friendly, sustainable, and facile characteristics. The ingenious strategy involves the addition of water to modulate the solvent environment of DES for the optimal growth of AuPt NFs. The results of nuclear magnetic resonance elucidate the water-DES interactions and interestingly reveal that a similar solvent environment within the water content range of 14.1-19.8 wt % is found, in which the well-defined AuPt NFs can be grown. Benefiting from the unique 3D self-supported flower-like structures and electronic synergistic effect of AuPt NFs-1catalyst, 98.5% cinnamaldehyde (CAL) can be converted, and the selectivity toward hydrocinnamaldehyde (HCAL) is as high as 93.2% after 6.0 h of the reaction at 60 degrees C under 1.0 H2 MPa. After 5 cycles, AuPt NFs-1 still maintains good catalytic performance achieving 97.3% CAL conversion and 90.1% HCAL selectivity. The innovative and eco-friendly synthesis strategy of producing 3D AuPt NFs will provide new insights into metal nanocatalysts for catalytic hydrogenation of CAL to HCAL, as well as various other applications.

The present study investigates the active phases and the role of oxygen species in the toluene oxidation process over CuCeZrOx catalysts prepared with bacterial cellulose (BC), and compares them with nitric acid pickling CuCeZrOx-BC(H) and CeZrOx-BC catalysts. The investigation is carried out using in-situ DRIFT, O2-TPD, H2-TPR, XRD, and TEM techniques. Our findings suggest that dispersed CuO species on the catalyst surface, Cu-Ce-Zr-O, and Ce-Zr-O solid solutions are active for toluene oxidation over CuCeZrOx-BC, with corresponding activities decreasing successively. The in-situ DRIFT results demonstrate that gaseous oxygen facilitates the chemisorption of toluene on active oxygen species, forming benzoyl oxide species and partially oxidizing the absorbed intermediates to benzyl alcohol at room temperature. Furthermore, lattice oxygen is experimentally found to be involved in the deep oxidation of toluene, and the lattice oxygen present in dispersed CuO species dominates the toluene oxidation process over CuCeZrOx-BC.

Catalytic properties of multiple metals deposited on TiO2 nanoparticles were investigated in the oxidation of toluene. Isovolume impregnation method prepared the catalysts containing Cu, Mn, Ni, Co, and Fe deposited on TiO2, including CeO2 and ZrO2. The effects of loaded metal oxides on the structure and activity of initial catalysts were investigated using various characterization techniques. Toluene's removal efficiency and CO2 selectivity in the catalyst system were classified as follows: CuCeZr/T > MnCeZr/T > NiCeZr/T > CoCeZr/T > FeCeZr/T. Presence of water vapor exhibits an inhibitory effect on the conversion of toluene, which diminishes at higher temperatures. One contribution of this paper is to obtain the oxidation pathway of toluene and the relationship between the activation energy of all-inclusive and elementary reactions based on the variation of infrared spectrum using Freeman-Carroll method. Another contribution is to clarify the share of Langmuir-Hinshelwood and Mars-van Krevelen mechanisms during the oxidation of toluene over CuCeZr/T catalyst by transient response experiments of isotopically labeled oxygen. These findings provide a feasible method for the design and synthesis of transition metal oxide catalysts for industrial applications.

Designing a mild and cost-saving one-step protocol to construct free-supporting 3D bimetallic nanomaterials is highly appealed in both academic research and industrial applications. In this work, large 3D AuPd nanoflowers (NFs) are grown and constructed at room temperature in water via an ionic liquid 1-butyl-3-methylimidazolium chloride ([Bmim]Cl)-directed method. The results show that the as-obtained AuPd NFs present opening and free-standing multi-level structures. Specifically, large AuPd NFs are built up by 2D leaves, the leaves are composed of many nanobranches, which consist of nanopetals with symmetric growth. It is shown that the [Bmim]Cl has an important effect on the construction of AuPd NFs. Meanwhile, the AuPd NFs exhibit superior catalytic activity toward both the degradation of organic dyes (methylene blue and Congo red) and the reduction of nitroaromatics (p-nitrophenol and p-nitroaniline). After six runs of the recycles, no obvious deactivation is found. The large AuPd NFs are also eagerly expected to have potentials in other applications including electrocatalysis and sensors.

采用溶胶凝胶法制备了双主金属、双助剂的CuxMn1-xCe0.75Zr0.25Oy催化剂,在固定床反应器中评价了催化剂降解甲苯的性能,并采用XRD、H2-TPR、O2-TPD和Raman对催化剂进行表征.试验结果表明:催化剂中Cu含量的增加有助于增强Cu-Ce金属之间的相互作用,增加催化剂中的氧空位浓度和晶格氧含量,提高催化剂低温还原性,从而促进催化活性的提高.Cu1CeZr催化剂降解甲苯活性最好,其完全降解甲苯的温度(T100)为220℃,比Mn1CeZr催化剂低60℃.

Conceiving a simple, green, and mild one-pot route to grow and construct anisotropic bimetallic 3D architectures with multilevel structures and promising functions is highly desirable and technical...

Fine construction of porous bimetallic nanomaterials with tunable components and structures is of great importance for their catalytic performance and durability. Herein, we present a facile and mild one-pot route for the preparation of porous PtPd bimetallic nanoparticles (NPs) with reversed structures in aqueous solution for the first time. To this end, a common ionic liquid (IL) 1-hexadecyl-3-methylimidazolium chloride ([C16mim]Cl) is utilized to direct the growth and assembly of porous structures of PtPd NPs. It is shown that the as-prepared porous Pt25Pd75 NPs have obvious hierarchical structures with nanoflowers as subunits and nanorods as basic units. The elemental components and structures of the porous PtPd NPs can be tuned by the precursor ratio and the [C16mim]Cl concentration. Furthermore, various porous PtPd bimetallic structures from Pd-on-Pt to Pt-on-Pd may be efficiently switched by controlling the concentration of glycine. Owing to their high specific surface area, porous hierarchical structures (including mesopores and micropores), and probable electronic effects between Pt and Pd, the porous Pt25Pd75 NPs (Pd-on-Pt structure) are found to exhibit prominent catalytic activity and high stability for hydrogen production from hydrolysis of ammonia borane.

采用简单的溶胶–凝胶法在不同的温度下制备Cu0.5Ce0.375Zr0.125Ox复合氧化物催化剂,通过XRD、H2-TPR、O2-TPD和Raman技术表征催化剂的结构,在固定床反应器中对其降解甲苯性能进行研究.结果表明:溶胶–凝胶的温度对催化剂的结构和活性具有一定影响,适宜的溶胶–凝胶温度有利于增强金属离子的流动性,促进CuO和CeO2的相互作用,使Cu2+更容易进入到CeO2晶格中形成Cu-Ce固溶体,形成缺陷结构,产生更多的氧空位.当催化剂制备的溶胶–凝胶温度为70℃时,催化剂降解甲苯的活性最好,其完全降解甲苯的温度为250℃.这归因于该催化剂具有高达0.95的氧空位浓度和对活性起主要作用的活性物种较高的耗氢量.

With the assistance of a functionalized ionic liquid, 1-hydroxyethyl-3-methylimidazolium chloride ([HEmim] Cl), the porous sponge-like AuPd nanomaterials was quickly one-pot synthesized in aqueous solution at room temperature. Using field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray energy spectroscopy (EDX) and X-ray diffraction (XRD), the structures and composition of as-prepared sponge-like AuPd nanomaterials were characterized and analyzed. The results show that the AuPd nanosponges have alloy structures and are formed via the aggregation and fusion of roughed nanoparticles. With different molar ratios of HAuCl4 and Na2PdCl4 precursors (3:1, 1:1 or 1:3), all the products prepared have sponge-like alloy structures. The ionic liquid plays an important role for the construction of AuPd sponge-like structures. Futhermore, all the as-obtained AuPd nanosponges exhibit excellent catalytic performance than commercial Pd/C in the reaction of p-nitrophenol reduction, in which the Au, Pd-3 nanosponges have the highest catalytic activity. In the presence of Au, Pd-3 nanosponges , the reaction can be finished within only 98 s and the reaction rate constant is calculated to be 0. 0143 s(-1), which is 2. 3 times higher than commercial Pd/C. Yet, the current protocol can be used to grow and assemble other bi-metallic (such as PdCu and PtCu) and multi-metallic nanosponges.

Highly active CuO-CeO2-ZrO2 catalysts were prepared by sol-gel method, using environmentally friendly bacterial cellulose (BC) as structure directing regent. The catalyst designed with commercial BC (Corn-BC) exhibited catalytic performances in toluene (T-100 = 220 degrees C) and ethyl acetate oxidation (T-100 = 170 degrees C) superior to the catalysts prepared by traditional methods. Furthermore, excellent stability was obtained and no deactivation was observed during the 100 h on stream in toluene and ethyl acetate oxidation at T-100. The excellent activity and stability of Corn-BC can be explained by the hierarchically porous structure, abundant oxygen vacancies, and good reducibility.

选用细菌纤维素(BC)、草酸(OA)和乙二醇(EG)为造孔剂,采用溶胶凝胶法制备了Cu-Mn双主金属Ce-Zr双助剂复合氧化物催化剂,在固定床反应器中评价了其催化降解甲苯的性能,用低温N2物理吸脱附、XRD、H2-TPR和Raman方法对催化剂进行表征.结果表明:催化剂的组成相同时,以生物基细菌纤维素为造孔剂制备得到的Cu0.25Mn0.25Ce0.375Zr0.125Ox-BC催化剂降解甲苯的活性明显高于化学造孔剂草酸和乙二醇制备的催化剂,其完全降解甲苯的温度为240℃,比化学造孔剂制备的催化剂低10～30℃;高的氧空位浓度(0.726)和好的低温还原性是Cu0.25 Mn0.25Ce0.375Zr0.125Ox-BC催化剂具有降解甲苯高活性的主要原因.

以TiO2为载体,采用等体积浸渍法制备了负载型CuxMn1-xCe0.75Zr0.25/TiO2(x=1.0、0.75、0.5、0.25、0)负载型催化剂,采用XRD、H2-TPR、O2-TPD和XPS等方法对催化剂进行了表征,并通过低温等离子体协同催化剂对大流量的甲苯模拟废气进行了催化降解反应研究.结果表明,Cu和Mn单主金属催化剂的活性优于Cu-Mn双主金属催化剂,其原因是双金属催化剂中Mn的添加减弱了Cu与助剂Ce之间的相互作用,使得催化剂的晶格氧减少,低温还原性能降低.在反应初期,甲苯降解主要依赖于催化剂的活性,具有较好的低温还原性以及丰富的氧空穴和晶格氧含量的CuCe0.75 Zr0.25/TiO2的活性最好;Mn具有较强的O3分解能力,当等离子体比能密度(SED)增加到一定值后,等离子体与催化剂的协同作用增强,从而使得MnCe0.75 Zr0.25/TiO2催化剂活性高于CuCe0.75 Zr0.25/TiO2,强化了甲苯的脱除.

在室温水溶液中,采用离子液体[C4 im]Cl调控合成了AuPd纳米刺球.采用多种表征技术对产品的形貌和结构进行了分析.研究结果表明:所制备的AuPd纳米刺球由0.5～1.0μm的球形颗粒组成.颗粒表面较为粗糙,有许多纳米级颗粒组成的尖刺,具有明显的微纳分级结构.同时,AuPd刺球在有机染料亚甲基蓝的降解过程中表现出良好的催化活性,整个反应过程仅需150 s,反应速率常数为0.0174 s-1,其催化活性是商用Pd/C催化剂的1.67倍.

The self-sustained combustion of toluene on the Cu-Ce-Zr based catalysts with different activity has been carried out in a micro-tube with inner diameter of 4 mm. It was shown that the lean-combustion limits over CuCe0.75Zr0.25Ox-BC catalyst with the higher activity were less than that on CuCe0.75Zr0.25/TiO2 catalyst at the same flow rate, and the minimum of equivalence ratio (?) was 0.024 under the flow rate of 200 ml/min. The residence time of the mixed gas on the catalyst surface declined with the increasing of flow rate, making the highest surface wall-temperature range shift to the back of catalyst bed. Toluene could maintain self-sustained combustion even when the heat loss was as high as 91.9%. Combined with the theoretical model, the heat transport of toluene self-sustained combustion in micro-tube was calculated. The self-sustained combustion in a fixed-bed reactor was realized with reducing the upper limit of temperature runaway??s impacts for the reactor and catalysts.

A series of CuCe0.75Zr0.25Ox catalysts (CCZ) were synthesized based on the environmental-friendly bacterial cellulose (BC) by using the sol-gel method. The corresponding synthesis mechanism, physicochemical properties of the catalysts and catalytic performances for toluene oxidation were comprehensively studied. In the presence of BC without sugar, the CCZ-A synthesized by ethanol-gel exhibits better catalytic activity than the CCZ-W synthesized by water-gel, which may be due to the different roles of BC in different solvents. However, it is worth noting that the graft copolymerization between BC and active metal (Ce4+, Cu2+) is the same process in both water-gel and ethanol-gel. The activity of CCZ-SW synthesized by water-gel using BC with sugar is obviously higher than that of CCZ-W and CCZ-A. The temperature of complete degradation of toluene over CCZ-SW is 205 degrees C, which is 35 degrees C lower than that of CCZ-W. The results from BET, Raman and H-2-TPR indicate that the larger the specific surface area, the more oxygen vacancies and better low-temperature reducibility, that are mainly responsible for the excellent activity of CCZ-SW. The existence of sugar in BC could hinder the agglomeration of active metal particles during the calcination process. Combined with the results of insitu DRIFT, the adsorbed toluene on the catalyst surface is oxidized into alkoxide, aldehydic and carboxylic acid species as intermediates before the complete oxidation into CO2 and H2O.((1))