Templating Agent Research Articles

Macroporous Mannitol Granules Produced by Spray Drying and Sacrificial Templating

In pharmaceutical applications, the porous particles of organic compounds can improve the efficiency of drug delivery, for example into the pulmonary system. We report on the successful preparation of macroporous spherical granules of mannitol using a spray-drying process using polystyrene (PS) beads of ~340 nm diameter as a sacrificial templating agent. An FDA-approved solvent (ethyl acetate) was used to dissolve the PS beads. A combination of infrared spectroscopy and thermogravimetry analysis proved the efficiency of the etching process, provided that enough PS beads were exposed at the granule surface and formed an interconnected network. Using a lab-scale spray dryer and a constant concentration of PS beads, we observed similar granule sizes (~1-3 microns) and different porosity distributions for the mannitol/PS mass ratio ranging from 10:1 to 1:2. When transferred to a pilot-scale spray dryer, the 1:1 mannitol/PS composition resulted in different distributions of granule size and porosity depending on the atomization configuration (two-fluid or rotary nozzle). In all cases, the presence of PS beads in the spray-drying feedstock was found to favor the formation of the α mannitol polymorph and to lead to a small decrease in the mannitol decomposition temperature when heating in an inert atmosphere.

Catalytic oxidation performance and ion-exchange of Ti-MWW zeolite membrane with dual organic template agents and potassium carbonate

In the absence of boric acid, the tubular Ti-MWW zeolite membranes are prepared with dual organic template agents and potassium carbonate by secondary hydrothermal synthesis. 12MR cage and 10 MR of the MWW zeolite topology structure is stabilized by TMAdaOH and HMI organic template agents, K+ cations is a critical mineralization agent for preparing Ti-MWW zeolite membrane with bi-layer Ti-MWW zeolites layer in this work. Besides, ion-exchange could greatly improve the catalytic performance of the Ti-MWW zeolite membrane for phenol hydroxylation with H2O2, influences of ammonium salt, ion-exchange time and temperature on the micro-structure and catalytic performance are investigated. The upper network-like Ti-MWW zeolite layer could be dissolved and removed by ion-exchange with 0.5 M (NH4)2SO4 solution at 60 °C for 24 h, and the “lying” Ti-MWW zeolites layer is kept on the mullite support. On the other hand, ion-exchange could promote the transformation of hexacoordinated extra-framework titanium species to tetracoordinated state in the framework, part of K+ cations of Ti-MWW zeolites are replaced with NH4+ cations. Total flux and phenol conversion of the ion-exchanged Ti-MWW zeolite membrane are 14.89 kg·m−2·h−1 and 36.49 % for phenol hydroxylation by H2O2 at 50 °C.

Design and synthesis of TiO2/ZnO nanocomposite with enhanced oxygen vacancy: Better photocatalytic removal of MB dye under visible light-driven condition

• TiO 2 /ZnO nanocomposite was synthesized by a facile hydrothermal route. • C. verum leaf extract was utilized as a bio-reducing and templating agent. • TiO 2 /ZnO (0.5mol) exhibited superior photocatalytic activity against MB dye removal. • TiO 2 /ZnO increases surface oxygen vacancy supressing recombination of e - -h + pair. • Excellent catalytic performance is owing to controlled surface oxygen vacancy and small particle size. Construction of capable, affordable, transition metal-based catalysts featuring photocatalytic behaviour is urgently required and important. Herein, for the first time we have synthesized an eco-friendly, capsule shaped ZnO nanoparticles (NPs) anchored upon TiO 2 nanoplates, by utilizing bio-active components available in Cinnamon verum leaf extract. The bio-active components, linalool and phytol served as a self-reducing and gapping agent that enrich the surface with oxygen vacancy without disrupting lattice arrangement. The XRD results confirms presence of wurtzite ZnO, anatase and rutile TiO 2 NPs. Anatase TiO 2 with ZnO supress the electron-hole pair recombination effect. The delayed luminescence behaviour is consistent with the UV-DRS results and suggests that the band gap of TiO 2 /ZnO has been widened. SEM with EDX results justifies that TiO 2 /ZnO nanocomposite mounted oxygen vacancy in a controlled phenomenon, which can boost the separation efficacy of photogenerated carriers and is in good agreement with the PL results. Under visible light irradiation for 60 minutes, TiO 2 /ZnO significantly improves photocatalytic degradation for aqueous organic dye pollutants. The k value of the TiO 2 /ZnO (0.5 mol) nanocomposite is 2.5x10 -2 mint -1 which is comparably higher. The unusual nanoarchitecture, high surface area, and wide band gap of TiO 2 /ZnO are primarily responsible for its noticeably improved photodegradation performance.

Surface dealuminated Beta zeolites supported WO3 catalyst and its catalytic performance in tetralin hydrocracking

In this study, selective dealumination of Beta zeolites was performed through partially removing the templating agent in Beta zeolites by calcination and then removing the aluminum on the external surface of Beta zeolites with acid treatment. Hydrocracking catalysts were prepared by loading WO 3 onto these dealuminated Beta zeolites. It was shown that the surface SiO 2 /Al 2 O 3 of selectively dealuminated Beta zeolites was higher than that of conventionally dealuminated samples for the same bulk SiO 2 /Al 2 O 3 , and the hydrogenation activity of the catalyst of the selectively dealuminated Beta zeolites was lower than that of conventionally dealuminated Beta zeolites. The experimental results for tetralin hydrocracking to BTX showed that the catalysts based on the selectively dealuminated Beta zeolites had higher BTX selectivity and lower coke formation rate than that the catalysts based on the conventionally dealuminated Beta zeolites.

Synthesis of Zn-Al layered double oxides using eucalyptus leaf extract as template for efficient and ultrafast thorium(IV) removal

Efficient capture of Th(IV) from aqueous solution is of importance to both solve the radioactive pollution for environmental safety and provide clean energy for sustainable development. However, it still faces huge challenge. In this study, eucalyptus leaf extract was applied as template agent to fabricate Zn/Al-bimetallic layered double oxides (ZnAlLDO), providing more active sites for Th(IV) removal. The removal process of Th(IV) onto ZnAlLDO could reach equilibrium within 5 min and the maximum removal capacity calculated from the Langmuir model was 1153.71 mg g−1 at pH = 4.0 and 298 K. Over 97 % Th(IV) could be removed by ZnAlLDO during the dynamic adsorption process and the removal efficiency still remained at a high level (85 %) after 5 cycles. The Th(IV) removal process on ZnAlLDO was ascribed to electrostatic attraction, complexation and ion exchange. It could be believed that the ZnAlLDO with large removal capacity (1155.5 mg g−1), fast equilibrium time (5 min) and easy desorption (91.76 %) with high recovery (85 %) might be a promising adsorbent for the separation of Th(IV).

Templating agent-mediated Cobalt oxide encapsulated in Mesoporous silica as an efficient oxone activator for elimination of toxic anionic azo dye in water: Mechanistic and DFT-assisted investigations

While Azorubin S (AZRS) is extensively used as a reddish anionic azo dye for textiles and an alimentary colorant in food, AZRS is mutagenic/carcinogenic, and it shall be removed from dye-containing wastewaters. In view of advantages of SO4•−-related chemical oxidation technology, oxone (KHSO5) would an ideal source of SO4•− for degrading AZRS, and heterogeneous Co3O4-based catalysts is required and shall be developed for activating oxone. Herein, a facile protocol is proposed for fabricating mesoporous silica (MS)-confined Co3O4 by a templating agent-mediated dry-grinding procedure. As the templating agent retained inside the ordered pores of MS (before calcination) would facilitate insertion and dispersion of Co ions into pores, the resulting Co3O4 nanoparticles (NPs) would be grown and confined within the pores of MS after calcination, affording Co@MS. On the contrary, another analogue, Co/MS, is also prepared using the similar protocol without the templating agent-mediated introduction of Co, but Co3O4 NPs seriously aggregate as clusters on MS. Therefore, Co@MS outperforms Co/MS for activating oxone to eliminate AZRS. Co@MS shows a noticeably lower activation energy of AZRS elimination than the existing catalysts, revealing its advantage over the reported catalysts. Moreover, the mechanistic investigation of AZRS elimination by Co@MS-activated oxone has been also elucidated for identifying the presence of SO4•‒, •OH, and 1O2 in AZRS degradation using scavengers, electron paramagnetic resonance spectroscopy, and semi-quantification. The AZRS decomposition pathway is also investigated and unveiled in details via the DFT calculation. These results validate that Co@MS appears as a superior catalyst of oxone activation for AZRS degradation.

Synergistic effect of cerium and structure directing agent on drug release behavior and kinetics

This work was mainly aimed at the study of the dual effect of cerium and structure directing agent template concentration, on vancomycin release profiles and kinetics from Ce-substituted mesoporous bioactive glasses (MBGs). MBG based on (20-x) B2O3 - 55 SiO2 – 20 CaO – 5 P2O5 – x Ce2O (x = 0, 1 and 3 mol %) was synthesized by the evaporation-induced self-assembly process using two molar ratios (0.01 and 0.02 molar ratio) of nonionic block copolymer Pluronic® 123 (P123) surfactant. The TGA-DTA, FTIR, and textural features analyses were carried out for the glasses. Moreover, the in vitro bone-forming activity and degradation analysis were tested using simulated body fluid (SBF). The drug loading capacity, drug release profile, and kinetics (using different kinetic models such as first order, Higuchi, Hixson-Crowell, and Baker-Lonsdale models) were determined using vancomycin as a drug model. The results showed that the isotherms of all MBGs fit with type IV isotherms, and the surface area of MBGs synthesized by 0.02 M template was higher than that prepared by 0.01 M, where it ranged from 174.05 m2.g−1 to 256.73 m2.g−1. The pore size diameter was decreased as cerium content increased in all MBGs (decreased from 5.44 to 3.54 nm). Moreover, the MBGs induced the formation of a bone-like apatite layer, and their biodegradation properties can be tailored by controlling glass composition. Furthermore, Ce-free MBGs showed the lowest drug adsorption and the highest drug release percentage. The drug release kinetic was best fitted with Higuchi and Baker-Lonsdale models which denoted that the mechanism of drug release from MBGs was a diffusion release from spherical particles. In conclusion, vancomycin release was controlled by the glass composition. Meanwhile, the MBGs synthesized in this study are proposed to be applied for bone regeneration, bone cancer treatment, and reducing the bacterial activity around the tumor site.Graphical abstract

A novel (CaO/CeO2)@CeO2 composite adsorbent based on microinjection titration-calcination strategy for CO2 adsorption

A simultaneous titration-calcination strategy was proposed to synthesize core–shell type (CaCO3/Ce(OH)CO3)@Ce(OH)CO3 precursors by titrating Ca2+ and Ce3+ into aqueous CO2 storage material (CO2SM) solution simultaneously without adding any templating agents or surfactants. After calcination at 900 °C, the novel core–shell type (CaO/CeO2)@CeO2 composite adsorbent with the strong stability of adsorption cycle was synthesized. The effects of Ca/Ce doping ratio, CO2SM dosage, drop rate and temperature conditions on the CO2 adsorption performance on the composite adsorbent during the calcium cycle were investigated. The synthetic adsorbent with a Ca/Ce doping ratio of 24: 1 had the strongest CO2 capture performance during the calcium cycle, and it mainly consisted of CaO and CeO2. The CO2 adsorption amount still maintained at about 430 mg/g after 15 cycles under the adsorption–desorption conditions at 750 °C and 900 °C. (CaO/CeO2)@CeO2 composite adsorbent is a core–shell structure with CeO2 as the shell and CaO/CeO2 as the liner, in which CeO2 is uniformly dispersed in CaO pore channels, which gives the adsorbent a stable pore structure and enhances the anti-sintering performance of Ca-based adsorbent. Due to the special property of CeO2, it can also promote the ion migration during the carbonation process, thus maintaining the adsorption activity. Density functional theory (DFT) calculations successfully explain why CeO2 can be used as an inert dopant to promote the adsorption of CO2. After that, the synthesis mechanism of core–shell adsorbent and the reaction mechanism of CO2 adsorption are proposed in conjunction with the series characterization. This work provides a new strategy for the efficient synthesis of Ca-based adsorbents with special morphology and a new idea for CO2 capture.

Construction of rational defective CPO-27-Ni using N, N-dimethyloctadecylamine as template towards enhanced adsorptive desulfurization from fuel

Deep desulfurization from fuel has gradually become a research hotspot with enhancing requirements of environmental protection. CPO-27-Ni was considered as one of promising adsorbents towards adsorption desulfurization by virtue of its prodigious high pore volume and high specific surface area. However, the dominant microporous channels in traditional CPO-27-Ni hinder the diffusion of thiophene sulfide and its derivatives with relatively large molecular size, which limits its desulfurization efficiency. Herein, we proposed a strategy to reasonably construct defective CPO-27-Ni with micro-mesoporous structure using N, N-dimethyloctadecylamine (DMA18) as a template, aim at improving the diffusion efficiency by introducing meso-pores. Different amounts of DMA18 were introduced to synthesize defective CPO-27-Ni (DMA18-C-X) by solvothermal method, and DMA18-C-0.5 (the mole ratio of added DMA18 to Ni2+ was 0.5) exhibited a satisfactory desulfurization performance. The dynamic breakthrough adsorption capacities of dibenzothiophene, benzothiophene and thiophene over the DMA18-C-0.5 were remarkably promoted, which were as high 3.79, 6.45 and 9.29 times as the traditional CPO-27-Ni, respectively. The crystal structure of CPO-27-Ni was not altered after adding template agent DMA18, while a uniform distribution of mesopores appeared. The largest mesopore attained a size of 2.8 nm, which effectively promoted the full exposure of more unsaturated Ni2+ active sites and enhanced the interaction between Ni2+ active sites and sulfides, resulting in strengthened adsorption desulfurization performance. This method of introducing proper defects to construct mesopores in MOFs provides some useful references for preparing high-efficiency desulfurization adsorbents.

In-situ synthesis of micro/mesoporous HZSM-5 zeolite for catalytic pyrolysis of lignin to produce monocyclic aromatics

Catalytic pyrolysis of lignin is a promising way for lignin upgrading. To date, commercial zeolites have been demonstrated to be active in lignin catalytic pyrolysis for monocyclic aromatics production, but usually exhibit low selectivity and fast deactivation during reaction. These are mainly attributed to the inadequate of mesoporous structure and improper acidic property of commercial zeolites. Herein, HZSM-5 zeolites with different micro/mesoporous morphology were synthesized via the green and energy-efficient in-situ synthesis method. The porous structure of the zeolites was regulated by adjusting the synthesis conditions, i.e., the concentration of tetrapropylammonium hydroxide (TPAOH, used as the microporous templating agent), the synthesis temperature, and synthesis duration. With the HZSM-5 sample synthesized under the optimal condition (S8HZ), the relative content of monocyclic aromatics achieved during lignin catalytic pyrolysis reached 39.3 % at 500 °C, which was much higher than that attained over the commercial HZSM-5 (17.3 %). In addition, the acidic property and pore structure of the S8HZ catalyst was further modulated by cobalt impregnation. The introduction of cobalt, rendered a good balance between the structural property and acidity of the catalyst, which eventually facilitated the generation of monocyclic aromatics by both improving mass transfer and reducing coke formation. As it turned out, 1 wt% of cobalt introduction to the S8HZ boosted the generation of monocyclic aromatics to 46.3 % at 550 °C. Moreover, the catalyst retained good stability in catalytic lignin pyrolysis after 10 reaction cycles. Overall, this work demonstrates the feasibility of using in-situ synthesized HZSM-5 catalyst with rich micro/mesoporous structure as well as Co modification for catalytic lignin upgrading to monocyclic aromatics, which offers new insights for lignin upgrading via catalytic pyrolysis.

Computer simulation of the early stages of self-assembly and thermal decomposition of ZIF-8.

We employ all-atom well-tempered metadynamics simulations to study the mechanistic details of both the early stages of nucleation and crystal decomposition for the benchmark metal-organic framework (MOF) ZIF-8. To do so, we developed and validated a force field that reliably models the modes of coordination bonds via a Morse potential functional form and employs cationic and anionic dummy atoms to capture coordination symmetry. We also explored a set of physically relevant collective variables and carefully selected an appropriate subset for our problem at hand. After a rapid increase of the Zn-N connectivity, we observe the evaporation of small clusters in favor of a few large clusters, which leads to the formation of an amorphous highly connected aggregate. Zn(MIm)4 2- and Zn(MIm)3 - complexes are observed with lifetimes in the order of a few picoseconds, while larger structures, such as four-, five-, and six-membered rings, have substantially longer lifetimes of a few nanoseconds. The free ligands act as "templating agents" for the formation of sodalite cages. ZIF-8 crystal decomposition results in the formation of a vitreous phase. Our findings contribute to a fundamental understanding of MOF's synthesis that paves the way to controlling synthesis products. Furthermore, our developed force field and methodology can be applied to model solution processes that require coordination bond reactivity for other ZIFs besides ZIF-8.

Template synthesis of nitrogen self-doped hierarchical porous carbon with supermicropores and mesopores for electrical double-layer capacitors

Nitrogen self-doped hierarchical porous carbon for electrical double-layer capacitors was synthesized by direct carbonization of bean dregs-based tar with potassium acetate as the template agent. The pore structure parameters and chemical element composition were adjusted by varying the heating rate during the carbonization process. The electrochemical properties of the electrode materials were evaluated in a three electrode system with 6 M KOH as the electrolyte. The resultant bean dregs-based porous carbons (BDPCs) exhibited high specific surface area, unique hierarchical architecture (consisting of supermicro- and mesopores), and medium nitrogen content (0.66 to 0.78%). The BDPC-10 sample had the highest specific surface area of 1610 m2/g and reasonable pore size distribution, and consequently exhibited an excellent specific capacitance of 363.7 F/g at the current density of 1 A/g. Nevertheless, the capacitance was reduced to 280.5 F/g at 3 A/g, giving a capacitance retention ratio of 77.1%. This study suggests a facile and environmentally friendly template synthesis process for supercapacitor electrode materials preparation, but it also faces challenges to increase the rate capability.

Ionic liquid-modulated synthesis of MnO2 nanowires for promoting propane combustion: Microstructure engineering and regulation mechanism

Manganese oxides for catalytic combustion of VOCs are high profile owing to their excellent redox properties and oxygen storage capacities, while the precise regulation of microstructure to improve the activity remains challenging. Herein, imidazolium-based ionic liquids are employed as the template agents to synthesize a range of MnO2 for different structures and morphologies. The hydrogen bonding network of the ionic liquid and the π-π stacking interactions between the imidazole rings promoted the self-organization of [MnO6] into a specific structure. In this process, alteration of alkyl chain length of ionic liquids caused changes in surface tension and steric hindrance, affecting the growth of MnO2. A series of characterization results showed that MnO2 transformed from nanofibers to nanorods when the alkyl chain elongated from ethyl to octyl, accompanied by an increase in crystal size. This transformation decreased the specific surface area and surface-active oxygen of the catalyst, diminishing active sites available for the catalytic reaction. Therefore, the optimal catalytic performance of the prepared catalyst was achieved when the ionic liquid was selected as 1-ethyl-3-methylimidazolium tetrafluoroborate, with a propane conversion of 90% at 289 ºC. This work provided a feasible path to realize the microstructure engineering of non-noble metal catalysts.

Valorizing high-fraction bio-oil to prepare 3D interconnected porous carbon with efficient pore utilization for supercapacitor applications

Heavy-fraction bio-oil (HB) is an underused product of biomass pyrolysis due to its difficulty in direct use or efficient refinery, but it is a potential carbon precursor to prepare porous carbon for energy storage. The fluid HB with structural flexibility and miscibility is desirable to fabricate tailored carbon structure. In this work, we developed an in-situ activation method to convert HB into carbon-based electrode for supercapacitor applications. HB was pre-mixed with KOH activator in aqueous phase and then formed a solid composite, thus the inserted KOH could act as both activator and template agent for pore generation. The resultant porous carbon exhibits a 3D interconnected framework with micropore dominant structure. Benefiting from the structural features, the moderate surface area contributes a high capacitance indicating the excellent pore utilization efficiency, which is superior to most activated carbons and the commercial electrode material YP-50F. Furthermore, the porous carbon shows outstanding energy density, power density and cycling stability in both aqueous and organic electrolyte, indicating a promising application potential. The valorization of HB not only provides a cost-effective electrode material for energy storage, but also promotes the comprehensive utilization from biomass pyrolysis technology.

Controllable synthesis and catalytic activity of bismuth silicate: Thin-layered photocatalysts with the effect of template agent

The heterogeneous bismuth silicate is a promising and environmental photocatalytic material. However, the cross-linked structure limits its catalytic activity. Here, we report a visible-driven composite photocatalyst with high catalytic activity, namely BOS-PS (layered Bi2O2SiO3-Si2Bi24O40 modified with template PS spheres), which can solve the problem. By controlling the concentration of template and changing the reaction time, the microscopic morphology can be adjusted to obtain effective heterojunction and heterogeneous interfaces as well as highly active exposed surfaces. In addition, compared with BOS (Bi2O2SiO3-Si2Bi24O40)-0PS (polystyrene microspheres), BOS-12PS has a thinner sheet structure, and the photocatalytic performance of BOS-12PS photocatalyst (98% within 90 min) is twice than that of BOS-0PS. The improved performance is mainly attributed to the increase of ·OH radicals and the modulation of its energy band structure by the oxygen defect level. Specifically, on the one hand, BOS-12PS has more ·OH radicals and can produce ·O2− on the surface. On the other hand, due to its upward-moving structure (Vo level), BOS-12PS plays an important role in the degradation of pollutants. Especially, the effective heterojunction formed by Bi2O2SiO3 and Si2Bi24O40 significantly improves the separation efficiency and redox capability of the sample.

Removal of bisphenol A (BPA) by fermented sludge-derived granular biochar from template-like method: From batch experiment to continuous operation

Endocrine disruptors have biological toxicity and can interfere with the endocrine system of organisms. They widely exist in natural water bodies. Here, the granular biochar was prepared from fermented sludge for the first time by using cationic polyacrylamide as template agent via a template-like method. The as prepared biochar was investigated for the removal of BPA in aqueous media by batch experiment and continuous flow experiment. The pyrolysis temperature and template concentration had a great influence on the properties of residual biochar and BPA capture. The static adsorption results show that when the template concentration was 1% with the pyrolysis temperature of 800 °C, the optimal biochar P-1%− 800 achieved the BPA adsorption value up to 84.78 mg/g. Its adsorption behavior, influencing factors, and recycling capability on BPA reduction were evaluated. Kinetics, isotherms and characterization analysis suggested that the adsorption mechanism involved pore filling, electrostatic attraction, π-π interactions and hydrogen bonding. Good regeneration performance, low concentration heavy metal leaching and lasting continuous flow stability in fixed-bed device under different water quality background demonstrated that fermented sludge-derived granular biochar P-1%− 800 is a desirable adsorbent for reducing BPA in complex water environment.

Catalytic one-pot conversion of biomass-derived furfural to ethyl levulinate over bifunctional Nb/Ni@OMC

As one of the important chemical feedstocks and biofuels, ethyl levulinate (EL) can be produced from biomass-derived furfural by consecutive hydrogenation, etherification and ring-opening reactions. However, this process normally requires two separate steps in different reaction systems, which is complex and energy consumption. Herein, Nb–Ni bifunctional ordered mesoporous carbons (Nb/Ni@OMCs) were synthesized by a two-step process where Ni@OMC was firstly synthesized by a solvent evaporation induced self-assembly (EISA) process using F127 as a template agent, polyphenol gallic acid as carbon precursor and Ni2+ as cross-linker, following with the supporting of Nb species in the Ni@OMC by an incipient wetness impregnation method. The as-synthesized Nb/Ni@OMC samples were applied for the one-pot catalytic transformation of furfural to EL, and exhibited good activity with the highest EL yield of 83% under an optimized condition. Two possible pathways for the one-pot production of EL were proposed according to two intermediates: (1) hydrogenation of furfural to form furfuryl alcohol (FFA) that is then etherified with ethanol to form 2-(ethoxymethyl)furan (2-EMF); and (2) acetalization and etherification of furfural with ethanol to produce 2-(diethoxymethyl)furan (2-DMF). Then both 2-DMF and 2-EMF are converted to EL through acid catalyzed ring opening reaction. The dominant reaction pathway varied with the properties of the catalyst and the applied reaction conditions.

Nanostructuring Polyaniline Using Non-Substituted Imidazolium-Based Ionic liquid as Polymerization Medium Enabling Faster Supercapacitor Operation

Non-substituted imidazolium-based protic ionic liquid, namely imidazolium hydrogen sulfate [Imi][HSO4], has been investigated as a polymerization medium for PANI (designated as PANI/PIL). The resulting material was then investigated as electrode materials for supercapacitors. [Imi][HSO4] was prepared via a one-step acid-base reaction, and its structure was confirmed by 1H NMR. [Imi][HSO4] displayed full miscibility with water owing to the charge density distribution of its ions. Furthermore, the binary mixture [Imi][HSO4]/water is highly acid (e.g. pH ~ 0.1 for [Imi][HSO4]/water in a weight ratio of 70/30). As the polymerization medium for PANI/PIL, [Imi][HSO4] plays the role of a soft template agent and induces nanostructured PANI formation with fibrillar morphology (as shown by SEM images) without affecting the typical structure of PANI (as confirmed by FT-IR analysis). Furthermore, PANI/PIL was obtained in emeraldine salt form without any undesirable byproduct. Moreover, the electrical conductivity was seven times superior to that of the conventional PANI (i.e. PANI/HCl) when measured by the four-probe technique of PANI/PIL (~ 21.8 S/cm). This improvement in the PANI/PIL’s electrical conductivity of as well as the fibrillar morphology of PANI/PIL positively influences its electrochemical performances and highlights the suitability of [Imi][HSO4] as a polymerization medium for PANI material.

Panax notoginseng powder -assisted preparation of carbon-quantum-dots/BiOCl with enriched oxygen vacancies and boosted photocatalytic performance

Low activity of photocatalysts is a serious bottleneck to the practical application of photocatalytic technology. In this paper, a series of BiOCl composite photocatalysts containing carbon quantum dots (CQDs) were successfully prepared by adding Panax notoginseng powder (PNP) to the solvothermal synthesis system of BiOCl as a template agent and a raw material for 0D CQDs. CQDs/BiOCl exhibit 2D flake structures and 3D flower-like microspheres self-assembled from thin flakes, holding rich oxygen vacancies (OVs). After detailed characterization, it was found that the amount of OVs on BiOCl could be regulated according to the amount of PNP added. The CQDs/OVs-BiOCl photocatalysts exhibit higher photogenerated charge separation efficiency and photocatalytic activity than the bare BiOCl. When the mass ratio of PNP/BiOCl is 1.0%, the photocatalyst demonstrates the maximum degradation activity for rhodamine B (RhB) and perfluorooctanoic acid (PFOA). In view of the solid observations, a photocatalytic enhancement mechanism of CQDs/BiOCl was elucidated.

Molten Salt Self-Template Synthesis Strategy of Oxygen-Rich Porous Carbon Cathodes for Zinc Ion Hybrid Capacitors.

Porous carbon materials are widely used in capacitive energy storage devices because of their chemical stability, low cost, and controllable textures. Molten salt self-template methods are powerful and sustainable synthesis strategies for preparing porous carbons with tunable pore textures and surface chemistries. Herein, we propose a self-template synthesis strategy for preparing oxygen-rich porous carbons (ORC) by directly carbonizing potassium chloroacetate (ClCH2COOK) as the single carbon source. The potassium chloride salts generated in the carbonization play the roles of the template and etchant agent in the pore formation process. The as-prepared ORC samples feature abundant mesopores (average pore sizes of 1.95-2.19 nm and mesopore ratio of 36.4%), high specific surface areas (1410-1886 m2 g-1), and high oxygen doping levels (4.3-8.2 atom %). The zinc ion hybrid capacitors with an ORC cathode exhibited an ultrahigh capacitance of 308 F g-1 at 0.5 A g-1 and a high energy density of 136.5 Wh kg-1 at a power density of 570 W kg-1. Density functional theory demonstrates that oxygen-containing functional groups are conducive to the adsorption of Zn ions. Our work proposes a general synthesis methodology for the synthesis of oxygen-rich porous carbons for a variety of electrochemical energy storage devices.