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A uniform Cs-promoted Ni/Al2O3 nanocatalyst prepared by using a reliable automatic system shows extremely high productivity as well as good stability and coke resistance. The improved stability with doped Cs was elucidated by computational studies.

Diverse methods have been developed for the synthesis of active nanocatalysts involving various heterogeneous catalytic reactions. Thus far, numerous trial-and-error runs have been done to find the effective and practical ways. In the present work, the All-In-One (AIO) reactor system with a well-designed synthesis program, now in pilot stage, was first exploited as a reliable synthesis tool to find the optimum conditions for the production of Ni nanocatalysts. Using an activated charcoal support, active Ni nanoparticles of 7.8–11.8 nm (labeled A001–A007 in the program) were produced. These were achieved using a melt-impregnation process, which was controlled by variations in the applied gas (N2 and H2) and temperature (400 °C, 450 °C, and 500 °C) used as critical factors in the calcination step. Based on the optimization of the reaction sequence, each Ni nanocatalyst could be prepared within 5 h and 22 min. In particular, the optimum Ni nanocatalyst (A006) with the smallest particle size (7.8 nm), prepared under H2 flow at 400 °C, exhibits the highest catalytic activity (0.748 mmol4-NP·gcat-1·s-1) among the Ni catalysts for 4-nitrophenol (4-NP) reduction to 4-aminophenol (4-AP). This activity is much higher than that of conventional supported Ni nanocatalysts (0.551 mmol4-NP·gcat-1·s-1) produced using the wetness method.

Copper oxide nanoparticles (CuO NPs) with a clean surface supported on carbon nanofibers (CNFs) in one-pot were prepared by simple solid-state grinding and aging followed by thermal treatment, yielding CuO nanoparticles with high (23.8 wt%) and uniform CuO loading in the absence of surfactants and solvent. The CuO NPs on CNFs (CuO/CNF) showed excellent catalytic activity in transforming a wide variety of alkynes into alkenyl boronates using B

The development of high-performance Ni catalysts including the formation and stabilization of active Ni nanoparticles with high surface areas by increasing their metal dispersion at the high metal loading have been major issues in the design of a compact reformer for hydrogen production. Herein, we first report a facile method based on the sequential melt infiltration process for creating highly dispersed Ni nanoparticles (~7.5 nm) incorporated into alumina support (Ni/Al2O3) with high Ni load (45 wt%). They showed much higher hydrogen productivity and reaction rate than that of the incipient wet-impregnated Ni catalyst and commercial Ni catalyst as well as good thermal stability in steam-methane reforming under harsh conditions.

In this paper, we describe a facile new synthetic method for making highly dispersed molybdenum disulfide nanoparticles (~ 3 nm) on Ketjenblack carbon (MoS2/KC) via particle incorporation and sequential sulfidation. The MoS2/KC nanocatalyst obtained showed a good onset potential value (0.83 V), high durability, and excellent methanol tolerance for the oxygen reduction reaction. We report a simple method for making highly dispersed molybdenum disulfide nanoparticles (~ 3 nm) on Ketjenblack carbon support for sustainable oxygen reduction reactions with good onset potential, high durability, and excellent methanol tolerance.

C5–C13 linear alpha(α) olefins (LAOs) are high-value-added chemicals acknowledged by industry. However, using catalysts to elevate the activity and selectivity of LAOs remains a major challenge for Fischer–Tropsch synthesis (FTS). Recently, researchers on catalyst design have reported enhanced LAO production via FTS, but a more detailed understanding of the electron interactions between the active particles and hydrocarbon products is still needed. In the present paper, we report theoretical and experimental results of a potassium (K)-promotion effect on an optimized iron-carbide nanocatalyst (i.e. a carbon-encapsulated iron-carbide nanoparticle supported on nitrogen-doped porous carbon: Fe5C2@C/NPC). The K-doped Fe5C2@C/NPC nanocatalyst shows excellent catalytic performance with a high CO conversion of up to 96.7% at 78 h time-on-stream, C5–C13 LAO selectivity of 16.5% and productivity of 5.9 CH2 μmol gcat−1 s−1, compared to those of the K-free Fe5C2@C/NPC catalyst. The computer simulation model also supports the positive effects of the catalyst with a small amount of K (ca. 1 wt%, K/Fe = 0.05) in the FTS reaction, which well-matched the experimental results.

Bimetallic Rh–Co nanoparticles supported on nitrogen-doped porous carbon (Rh–Co/NPC) were synthesized from metal precursors and urea through a simple thermal decomposition/reduction under a nitrogen flow. The Rh–Co/NPC nanocatalyst which contains highly dispersed alloy nanoparticles (∼6 nm) showed high catalytic performance as well as good recyclability for the C–Se coupling reaction of diphenyl diselenide and aryl boronic acid and p-nitrophenol reduction.

Background Oxaliplatin as part of XELOX regimen has a more favorable toxicity profile than cisplatin for patients with advanced gastric cancer (GC). However, oxaliplatin can induce sensory neuropathy, a cumulative, dose-related toxicity. Thus, capecitabine maintenance regimen might achieve maximum treatment effect while reducing cumulative neurotoxicity of oxaliplatin. The aim of this study was to compare survivals of AGC patients between capecitabine maintenance and observation after 1st line XELOX chemotherapy. Methods Sixty-three patients treated with six cycles of XELOX for AGC in six hospitals of the Catholic University of Korea were randomized 1:1 to capecitabine maintenance or observation. The primary end point was PFS (PFS) analyzed using a two-sided log-rank test stratified at 5% significance level. Results Between 2015 and 2020, 32 and 31 patients were randomized to maintenance and observation groups, respectively. After randomization, the median number of cycles for maintenance capecitabine was 6. PFS was significantly higher for the maintenance group (6.3 months vs. 4.1 months, P = 0.010). OS (OS) was not significantly different between the two groups (18.2 months vs. 16.5 months, P = 0.624). Toxicity such as hand-foot syndrome was reported in some cases of the maintenance group. Maintenance treatment was a significant factor associated with PFS in multivariate analysis (HR: 0.472, 95% CI: 0.250-0.890, P = 0.020). Conclusions After six cycles of XELOX chemotherapy, capecitabine maintenance significantly prolonged PFS than observation and toxicity was manageable. Maintenance treatment was a significant prognostic factor associated with PFS.

Nickel (Ni)-based materials have been shown as good catalysts for hydrogen production by steam reforming of methane, but the hydrogen productivity has been restricted due to agglomeration among particles on Ni loaded catalysts. A new strategy is demonstrated by which to produce ultimate nickel nanocatalysts with high particle dispersion and high metal loading by using automated and systematic synthesis tools based on a simple melt-infiltration process and thermal treatment. The systematic sequence can yield highly dispersed Ni nanoparticles (4.5 nm) with high metal loading (25 wt%) on porous alumina (u-Ni/Al2O3) as an ultimate catalyst.

Tin(IV) oxide (SnO2) is the catalyst most commonly used for electrochemical reduction of CO2 into formate. However, the electrocatalytic performance of SnO2 is not ensured due to its poor long-term stability. Here, we report our study on the electrochemical stability of SnO2 for 152 h and describe an approach to achieve stable SnO2 electrodes using a γ-alumina (γ-Al2O3) support. The γ-Al2O3 reduces the leaching of Sn from the supported-SnO2 during CO2 electrolysis due to the strong interaction of the support with the electrocatalyst. This maintains the particle size, morphology, and crystallinity of SnO2. Thereby, pulverization of SnO2 is prevented and stable selectivity towards CO2 reduction results. The prepared SnO2/γ-Al2O3 exhibits much more stable Faradaic efficiency (65.0% at 152 h) and partial current density (21.7 mA cm−2 at 152 h) for formate synthesis than does unsupported SnO2 electrocatalyst (14.2% Faradaic efficiency; 4.6 mA cm−2 of partial current density at 152 h).

For the highly productive nanocatalyst synthesis, ensuring the formation and stabilization of active nanoparticles with enlarged surface areas by increasing their metal loading and dispersion have been major issues. Herein, we report a facile method based on a simple melt-infiltration process for creating extremely productive Fe5C2 nanoparticles (∼14 nm) incorporated into graphene flakes (Fe5C2/G) with a stable and high Fe load (∼35 wt%). They showed extremely high C5+ hydrocarbon productivity (4.41 gC5+HC gcat−1 h−1), CO conversion (91.8%), and Fe time yield (6.5 × 10−4 molCO gFe−1 s−1) as well as good thermal stability in CO hydrogenation reactions under harsh conditions.

Efficient catalysts for energy conversation from wastewater and energy storage are still existing. The effective hydrogen energy production through lower energy consumption is considered as a promi...

Iron-based nanoparticles with uniform and high particle dispersion, which are supported on carbon structures, have been used for various applications. However, their preparation still suffers from complicated synthesis involving multiple steps and from the high price of precursors and solvents. In the present work, a new carbon encapsulated iron-carbide nanoparticle supported on nitrogen-doped porous carbon (Fe5C2@C/NPC) structure was introduced. It was made using a simple solid-state reaction with sequential thermal treatments. Fe5C2@C/NPC is a highly active and stable catalyst for the high-temperature Fischer-Tropsch synthesis reaction. It showed very high hydrocarbon productivity (4.71 gHC·gcat−1·h−1) with high CO conversions (up to 96%).

The mesoporous hematite cubic frameworks (α-Fe2O3 microcube) with 2–3 μm sizes were prepared using a simple thermal treatment of the iron oxalate hydrate cubes (4 μm). The α-Fe2O3 microcube structure with a high surface area (36 m2 g−1) had three-dimensionally connected small grain sizes (˜18 nm). In formaldehyde (HCHO) gas sensing, the fabricated device by α-Fe2O3 microcubes shows excellent detection ability even at low HCHO concentration (˜50 ppb) and high response reaching to Rgas/Rair = 5.2 at 1 ppm as well as long-term stability, compared with conventional Fe2O3 nanoparticles.

Synthetic methods of mesoporous silica using surfactants or ionic liquids as a template have several disadvantages to commercialization such as low economic feasibility and low sustainability. Thus...

Improvement of activity, selectivity, and stability of the catalyst used in Fischer-Tropsch synthesis (FTS) to produce targeted hydrocarbon products has been a major challenge. In this work, the potassium-doped iron-carbide/alumina (K-Fe5C2/Al2O3), as a durable nanocatalyst containing small iron-carbide particles (∼ 10 nm), was applied to high-temperature Fischer-Tropsch synthesis (HT-FTS) to optimize the production of linear alpha olefins. The catalyst, suitable under high space velocity reaction conditions (14–36 N L gcat−1 h−1) based on the well-dispersed potassium as an efficient base promoter on the active iron-carbide surface, shows very high CO conversion (up to ∼90%) with extremely high activity (1.41 mmolCO gFe−1 s−1) and selectivity for C5–C13 linear alpha olefins.

A better understanding of clinician and patient characteristics that are associated with referral for palliative care in a real‐world context may help to overcome barriers to timely palliative care access. This article reports patterns of outpatient palliative care referral among thoracic medical oncologists and identifies oncologist characteristics associated with greater referral., Background. There is significant variation in access to palliative care. We examined the pattern of outpatient palliative care referral among thoracic medical oncologists and identified oncologist characteristics associated with greater referral. Materials and Methods. We retrieved data on all patients who died of advanced thoracic malignancies at our institution between January 1, 2007, and December 31, 2012. Using median as a cutoff, we defined two groups (high‐referring and low‐referring oncologists) based on their frequency of referral. We examined various oncologist‐ and patient‐related characteristics associated with outpatient referral. Results. Of 1,642 decedents, 444 (27%) had an outpatient palliative care referral. The median proportion of referral among 26 thoracic oncologists was 30% (range 9%–45%; median proportion of high‐referring 37% vs. low‐referring 24% when divided into two groups at median). High‐referring oncologists were significantly younger (age 45 vs. 56) than low‐referring oncologists; they were also significantly more likely to refer patients earlier (median interval between oncology consultation and palliative care consultation 90 days vs. 170 days) and to refer those without metastatic disease (7% vs. 2%). In multivariable mixed‐effect logistic regression, younger oncologists (odds ratio [OR] = 0.97 per year increase, 95% confidence interval [CI] 0.95–0.995), younger patients (OR = 0.98 per year increase, 95% CI 0.97–0.99), and nonmetastatic disease status (OR = 0.48, 95% CI 0.29–0.78) were significantly associated with outpatient palliative care referral. Conclusion. The pattern of referral to outpatient palliative care varied widely among thoracic oncologists. Younger oncologists were not only referring a higher proportion of patients, but also referring patients earlier in the disease trajectory. Implications for Practice. This retrospective cohort study found that younger thoracic medical oncologists were significantly more likely to refer patients to outpatient palliative care and to do so earlier in the disease trajectory compared with older oncologists, even after adjusting for other known predictors such as patient demographics. The findings highlight the role of education to standardize palliative care access and imply that outpatient palliative care referral is likely to continue to increase with a shifting oncology workforce.

Catalytic reduction by the reverse water gas shift (RWGS) reaction is an efficient way to utilize carbon dioxide and reduce its environmental impact as a greenhouse gas. In this research, an active CuFe/Al 2 O 3 nano powder was developed as a high temperature reforming catalyst for the RWGS reaction. The powder was synthesized by a wet-impregnation method and the copper alloy was uniformly dispersed on the γ-Al 2 O 3 support. At a gas space velocity of 60,000 h −1 , the conversion of carbon dioxide was 42% at 700 °C, which is very close to the equilibrium conversion of 44%. The results indicated excellent reforming activity of the CuFe/Al 2 O 3 catalyst for the high temperature RWGS reaction. In addition, the catalyst was applied in the form of a reforming layer over a conventional Ni-based electrode of a solid oxide electrolysis cell (SOEC) for an integrated SOEC-RWGS system. Hydrogen produced from steam electrolysis over the Ni-based cathode can be efficiently utilized to reduce the carbon dioxide by the RWGS reaction over the CuFe/Al 2 O 3 -based reforming layer. In this bilayer design, the reforming layer maintained the high surface area necessary for achieving good reforming activity, while the electrode layer possessed a high degree of sintering to enhance its electrochemical function. A high conversion of carbon dioxide (37% at 700 °C) was obtained in our bilayer SOEC-RWGS system. This promising result suggests the feasibility of the integrated SOEC-RWGS system for an efficient co-electrolysis device.

Hollow nanomaterials have attracted great interest because of their many applications in catalysis, nanoreactors, drug delivery systems, for lubrication and in gas sensors. Here, carbon sphere templates were prepared from glucose under hydrothermal conditions to facilitate the synthesis of hollow Fe2O3 nanospheres. Thermal decomposition of an iron precursor in benzylalcohol with the carbon spheres resulted in the deposition of Fe3O4 nanoparticles on the carbon sphere templates. The nanoparticles on the carbon surface naturally agglomerate and form a dense oxide shell during the calcination step, which produces typical Fe2O3 hollow structures. The gas sensing performance of the hollow Fe2O3 nanospheres was investigated at an operating temperature of 300 °C. The hollow Fe2O3 nanospheres showed high sensitivity (R = 10.766 at 1 ppm formaldehyde) with a linear response to formaldehyde gas concentration in the range of 0.8~2.4 ppm, and good selectivity to formaldehyde gas in volatile organic compounds, compared to commercial Fe2O3 nanoparticles.

A hierarchical architecture designated as Fe5C2@Ns-rGO/CNT, consisting of carbon nanotubes, steam activated N-doped reduced graphene oxides, and activated iron carbide nanoparticles, was prepared via microwave irradiation and subsequent CO activation. The Fe5C2@Ns-rGO/CNT was successfully applied to a rapid CO hydrogenation reaction showing extremely high activity of 4.4 × 10−3 molCO gFe−1 s−1 at a fast gas velocity of 210 NL gcat−1 h−1.

Mesoporous SiO2-supported Cu2O nanoparticles as an egg-shell type catalyst were prepared by impregnation method. The obtained Cu2O/SiO2 egg-shell nanocatalyst had a large surface area and narrow pore size distribution. In addition, most of the Cu2O nanoparticles, with sizes around 2.0 nm, were highly dispersed in the mesoporous silica. Accordingly, fast reactant diffusion to the active sites would occur, especially when the active metal sites are selectively located on the outer part of the support, i.e., the outer region of the egg shell. In solvent-free Sonogashira reactions for the synthesis of ynones from acyl chlorides and terminal alkynes, this catalyst exhibited a very high catalytic activity. The excellent catalytic performance can be attributed to the synergistic advantages of mesoporous structure and monodispersed Cu2O nanoparticles.

The production of shape-controlled heterometallic nanoparticles (NPs) consisting of Pt and nonprecious metal oxides is crucial to demonstrate the composition–property relationship of NPs. Herein, we report a facile one-pot approach for the controlled synthesis of dumbbell-like Pt–Fe3O4–MnOx and dendritic Pt–MnOx NPs. The key to the success of this synthesis is in changing the quantity of Fe(CO)5 additive to control the reaction kinetics. In the absence of Fe(CO)5, dendritic Pt–MnOx NPs were synthesized through the assembly of small seed NPs. On the other hand, dumbbell-like Pt–Fe3O4–MnOx NPs were obtained in the presence of Fe(CO)5 through controlling the nucleation and growth of Fe and Mn on the Pt NPs, followed by air oxidation. Compared to a Pt/graphene oxide (GO) catalyst, dumbbell-like Pt–Fe3O4–MnOx NPs on GO showed an enhancement of specific activity toward the oxygen reduction reaction owing to the compressive-strain effect exerted on the Pt lattice.

Highly-loaded and well-dispersed Fe 5 C 2 nanoparticles within ordered mesoporous carbon CMK-3 (Fe 5 C 2 @CMK-3) were prepared via a simple melt infiltration method. They were successfully applied to high-temperature Fischer-Tropsch synthesis, and showed high CO conversion (91%) and activity (5.1 × 10 −4 mol co g Fe −1 s −1 ) as well as good selectivity (38 wt%) for gasoline-range hydrocarbons (C 5 –C 12 ). The catalytic property of Fe 5 C 2 @CMK-3 was newly interpreted, based on theoretical data obtained by computational simulations.

Nickel-based catalysts have been applied to the catalytic reactions for transfer hydrogenation of carbonyl compounds. In the present work, highly dispersed nickel particles located at the pores of mesoporous silica spheres (Ni@mSiO2) were prepared via an optimized melt infiltration route. The nickel nanoparticles of 10 wt% in the Ni@mSiO2 catalyst could be uniformly loaded with high dispersion of 36.3%, resulting excellent performance for catalytic transfer hydrogenation of aryl ketones.

A cobalt-silica hybrid nanocatalyst bearing small cobalt particles of diameter ~5 nm was prepared through a hydrothermal reaction and hydrogen reduction. The resulting material showed very high CO conversion (>82%) and high hydrocarbon productivity (~1.0 gHC·g−1 cat·h−1) with high activity (~8.5 × 10−5 molCO·g Co −1 ·s−1) in the Fischer–Tropsch synthesis reaction.

Large-scale synthesis of cobalt nanoparticles supported on alumina (Co/Al2O3), which has well dispersed metallic cobalt around 15 nm, was conducted via a simple melt infiltration process of a cobalt hydrate salt and subsequent thermal reduction. The catalytic performance of Co/Al2O3 was studied for Fischer–Tropsch synthesis in order to optimize the liquid fuel productivity for target hydrocarbon products controlled by reaction pressures and temperatures. The catalyst showed promising CO conversions up to 76% with high hydrocarbon productivity (∼1.0 gHC gcat−1 h−1) and good stability.

The high-temperature Fischer–Tropsch synthesis reaction has been exploited to selectively produce lower-olefins and gasoline-range hydrocarbons (C5–C12) from a mixture of carbon monoxide and hydrogen, using iron-based catalysts. For this reaction, improving the selectivity and stability of the catalyst has been a major challenge, as has enhancing the activity. In the present work, we introduce iron-carbide nanoparticles supported on a porous gamma-alumina framework as a robust catalyst, prepared via a simple melt infiltration process and subsequent thermal treatment, for high-temperature Fischer–Tropsch synthesis. The iron-carbide/alumina catalyst showed much better catalytic performance, with a higher stability for producing gasoline-range hydrocarbon products, than did iron-carbide/mesoporous silica (SBA-15) and iron-carbide/activated carbon (AC).

Purpose Breast cancer treatment has progressed significantly over the past 20 years. However, knowledge regarding male breast cancer (MBC) is sparse because of its rarity. This study is an investigation of the clinicopathologic features, treatments, and clinical outcomes of MBC. Materials and methods Clinical records of 59 MBC patients diagnosed during 1995-2014 from seven institutions in Korea were reviewed retrospectively. Results Over a 20-year period, MBC patients accounted for 0.98% among total breast cancer patients, and increased every 5 years. The median age of MBC patientswas 66 years (range, 24 to 87 years). Forty-three patients (73%) complained of a palpable breast mass initially. The median symptom duration was 5 months (range, 1 to 36 months). Mastectomy was performed in 96% of the patients. The most frequent histology was infiltrating ductal carcinoma (75%). Ninety-one percent of tumors (38/43) were estrogen receptor-positive, and 28% (11/40) showed epidermal growth factor receptor 2 (HER-2) overexpression. After curative surgery, 42% of patients (19/45) received adjuvant chemotherapy; 77% (27/35) received hormone therapy. Five out of ten patients with HER-2 overexpressing tumors did not receive adjuvant anti-HER-2 therapy, while two out of four patients with HER-2 overexpressing tumors received palliative trastuzumab for recurrent and metastatic disease. Letrozole was used for one patient in the palliative setting. The median overall survival durations were 7.2 years (range, 0.6 to 17.0 years) in patients with localized disease and 2.9 years (range, 0.6 to 4.3 years) in those with recurrent or metastatic disease. Conclusion Anti-HER-2 and hormonal therapy, except tamoxifen, have been underutilized in Korean MBC patients compared to female breast cancer patients. With the development of precision medicine, active treatment with targeted agents should be applied. Further investigation of the unique pathobiology of MBC is clinically warranted.

Ordered mesoporous carbon materials are becoming increasingly important in catalysis applications due to their advantageous stability and surface properties. In this paper, we report a replication of the synthesis of mesoporous carbon CMK-3 using SBA-15 as a silica template. Ni/CMK-3 was prepared by incorporating Ni particles formed inside the pores of CMK-3 by impregnation of nickel nitrate and subsequent hydrogen reduction. The prepared Ni/CMK-3 has a large surface area and a very small nickel nanoparticle size (1 nm) with the aim of achieving high performance in catalytic hydrogenation reactions. Moreover, we demonstrate that CMK-3 has a higher stability than that of SBA-15 during the hydrogenation reactions of acetophenone derivatives.

Magnetite (Fe3O4) nanoparticles supported on charcoal, graphene, or SBA-15 were prepared by a simple solid-state grinding technique and subsequent thermal treatment. The Fe3O4 nanoparticles supported on activated charcoal exhibited high catalytic activity and furnished good yields of the alkynyl selenide product in the cross-coupling reaction of diphenyl diselenide and alkynes through activation of C−H and Se−Se bonds under ecofriendly conditions, surpassing traditional copper-based catalysts to effect the same organic transformation.

A small, stationary reformer designed as a stand-alone and self-sustaining type was developed for on-site hydrogen (H2) production. We created a compact reformer to produce H2 at a rate of 1 Nm3/h using the previously reported reaction kinetics of steam methane reforming (SMR). Both catalysts for the compact reformer - i.e., 15 wt% and 20 wt% Ni/γ-Al2O3 - showed good activity, with CH4 conversion exceeding 90% at 655 °C and a contact time of 3.0 gcath/mol, which were considered critical thresholds in the development of a small, compact stationary reformer. At an H2 production rate of 1 Nm3/h, the catalyst amount was calculated to be 167.8 g and the reformer length required to charge the catalyst was 613 mm, with a diameter of 1 inch. The CH4 conversion and H2 production rates achieved with the compact reformer using the 20 wt% Ni/γ-Al2O3 catalyst at 738 °C were 97.9% and 1.22 Nm3/h, respectively. Furthermore, a heat-exchanger type reformer was developed to efficiently carry out the highly endothermic SMR reaction for on-site H2 production. This reformer comprised a tube side (in which the catalysts were charged and the SMR reaction took place by feeding the reactants) and a shell side (in which the heat for the endothermic reaction was supplied by CH4 combustion). Reforming activities were evaluated using the active 20 wt% Ni/γ-Al2O3 catalyst, depending on the reactants' gas hourly space velocity (GHSV). The H2 production rate increased as the GHSV increased. Finally, the reformer produced a CH4 conversion of 98.0% and an H2 production rate of 1.97 Nm3/h at 745 °C, as well as a high reactants' GHSV of 10,000 h−1. Therefore, the heat-exchanger type reformer proved to be an effective system for conducting the highly endothermic SMR reaction with a high reactants' GHSV to yield a high rate of H2 production.

A one-pot synthesis of rose-like Pd–Fe 3 O 4 nanocomposites via the controlled thermal decomposition of Fe(CO) 5 and reduction of Pd(OAc) 2 is reported. This rose-like Pd–Fe 3 O 4 composite structure has a high surface area owing to the individual Pd–Fe 3 O 4 nanosheets, which imparted a high catalytic activity for Sonogashira coupling reactions. Moreover, the catalyst also demonstrated magnetic recyclability.

Nanocrystalline iron ore particles were fabricated by a wet-milling process using an Ultra Apex Mill, after which they were used as raw materials of iron-based catalysts for low-temperature Fischer-Tropsch synthesis (FTS) below 280 degrees C, which usually requires catalysts with a high surface area, a large pore volume, and a small crystallite size. The wet-milling process using the Ultra Apex Mill effectively destroyed the initial crystallite structure of the natural iron ores of several tens to hundreds of nanometers in size, resulting in the generation of nanocrystalline iron ore particles with a high surface area and a large pore volume. The iron-ore-based catalysts prepared from the nanocrystalline iron ore particles effectively catalyzed the low-temperature FTS, displaying a high CO conversion (about 90%) and good C5+ hydrocarbon productivity (about 0.22 g/g(cat)(-h)). This demonstrates the feasibility of using the iron-ore-based catalysts as inexpensive and disposable catalysts for the low-temperature FTS.

Temperature-programmed reduction using H2 (H2-TPR) and CO (CO-TPR) was carried out to investigate the reduction and carburization behavior of nanocrystalline ferrihydrite-based Fe/Cu/K/SiO2 catalysts for use in Fischer-Tropsch synthesis (FTS). Unlike pure ferrihydrite, the ferrihydrite-based catalysts did not pass through the intermediate decomposition step of ferrihydrite (Fe9O2(OH)23) into hematite (a-Fe2O3) as they were reduced into magnetite (Fe3O4). This is attributed to the enhanced thermal stability induced by SiO2. For the ferrihydrite-based catalysts, the reduction of ferrihydrite into magnetite occurred in two stages because the reduction promoter, Cu, is not homogeneously distributed on the catalyst surfaces. The Cu-rich sites are likely to be reduced in the first stage, and the Cu-lean sites may be reduced in the second stage. After the ferrihydrite is reduced to magnetite, the reduction process of magnetite was similar to that for conventional hematite-based FTS catalysts: 'magnetite --> metallic iron' and 'magnetite --> wustite (FeO) or fayalite (Fe2SiO4) --> metallic iron' in the H2 atmosphere; 'magnetite --> iron carbides' in the CO atmosphere.

This study investigated the effect of impregnating Ba into an Al2O3 catalyst on the acid-base property and catalytic activity in the dehydration of 1-octanol to produce 1-octene. The Ba/Al2O3 catalysts were prepared by the incipient wetness method with different Ba contents of 0.0–3.0 wt%, and characterized by ICP-MS, BET-BJH, XRD, pyridine-FTIR, and CO2-TPD. The catalytic activity in 1-octanol dehydration was evaluated at 300, 350, and 400 °C with liquid hourly space velocity (LHSV) of 7–56 h−1. As the amount of Ba increased, the density of the basic site on Ba/Al2O3 increased, and the strength distribution of the Lewis acid site (LAS) was changed. Under the reaction condition of 400 °C and LHSV = 7 h−1, Ba/Al2O3 showed higher 1-octene selectivity and 1-octene purity compared with the pure Al2O3 even though the 1-octanol conversion was similar. This is because the added Ba eliminated the strong LAS, which, in turn, inhibited the side-reaction originating from the re-adsorption of 1-octene. When LHSV > 21 h−1, Ba/Al2O3 catalysts showed decreased 1-octanol conversion but maintained high 1-octene selectivity and 1-octene purity. As the Ba content reached 2.0 wt%, 1-octene selectivity was decreased as the formation of dioctyl ether became more active than olefin production. Therefore, 1.5 wt% Ba/Al2O3 is the optimal catalyst for producing 1-octene from 1-octanol in terms of 1-octanol conversion, 1-octene selectivity, and 1-octene yield.

To upgrade odd numbered α-olefins derived from FTS residues, the heterogeneous hydroformylation of 1-heptene as a model compound for odd numbered α-olefin was investigated. Single crystalline Co3O4 nano catalysts with different morphologies (cube and octahedron) were synthesized using a hydrothermal method and were applied to the reductive hydroformylation of 1-heptene. HRTEM and SEM analysis indicated that the cubic and octahedral Co3O4 predominantly exposed well-defined crystal planes of {100} and {111}, respectively. The Co3O4 octahedron catalyst with highly exposed {111} facets had higher activity for hydroformylation than the Co3O4 cube catalyst. The Co3O4 octahedron catalyst with a {111} surface was easily reduced to CoO at lower temperature. These reduced cobalt species can be converted into cobalt carbonyl and improved reactivity with carbon monoxide, hydrogen and olefin, leading to better catalytic performance for hydroformylation than Co3O4. On the other hand, the Co3O4 cube catalyst with the {100} surface only exhibited the isomerization of 1-heptene.

Mo2C/graphene nanostructures were used to investigate the nature of gas-phase formic acid decomposition into either CO/H2O or CO2/H2 products. The experimental data show that the Mo2C/graphene can facilitate both decarboxylation and dehydration pathways for the formic acid decomposition reaction. Its selectivity is strongly influenced by the reaction temperature where the decarboxylation predominates at a low temperature (e.g., ≤ 280 °C) and the dehydration predominates at a high temperature (e.g., ≥ 370 °C). These experimental data are compared to Monte Carlo simulations. It was found that the decarboxylation pathway for the production of CO/H2O can be simulated and explained by an Eley-Rideal type mechanism that involves interaction of gas-phase HCOOH with surface H*. Furthermore, the dehydration pathway for the production of CO2/H2 can be simulated and explained by a Langmuir-Hinshelwood type mechanism that involves unimolecular decomposition of surface HCO*O* to form CO2 and H*.