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Strong metal–support interactions (SMSI) is an important concept in heterogeneous catalysis. Herein, we demonstrate that the Au‐TiO2 SMSI of Au/TiO2 catalysts sensitively depends on both Au nanoparticle (NP) sizes and TiO2 facets. Au NPs of ca. 5 nm are more facile undergo Au‐TiO2 SMSI than those of ca. 2 nm, while TiO2 {001} and {100} facets are more facile than TiO2{101} facets. The resulting capsulating TiO2−x overlayers on Au NPs exhibit an average oxidation state between +3 and +4 and a Au‐to‐TiO2−x charge transfer, which, combined with calculations, determines the Ti:O ratio as ca. 6:11. Both TiO2−x overlayers and TiO2−x‐Au interface exhibit easier lattice oxygen activation and higher intrinsic activity in catalyzing low‐temperature CO oxidation than the starting Au‐TiO2 interface. These results advance fundamental understanding of SMSI and demonstrate engineering of metal NP size and oxide facet as an effective strategy to tune the SMSI for efficient catalysis. [ABSTRACT FROM AUTHOR]

Strong metal–support interactions (SMSI) is an important concept in heterogeneous catalysis. Herein, we demonstrate that the Au‐TiO2 SMSI of Au/TiO2 catalysts sensitively depends on both Au nanoparticle (NP) sizes and TiO2 facets. Au NPs of ca. 5 nm are more facile undergo Au‐TiO2 SMSI than those of ca. 2 nm, while TiO2 {001} and {100} facets are more facile than TiO2{101} facets. The resulting capsulating TiO2−x overlayers on Au NPs exhibit an average oxidation state between +3 and +4 and a Au‐to‐TiO2−x charge transfer, which, combined with calculations, determines the Ti:O ratio as ca. 6:11. Both TiO2−x overlayers and TiO2−x‐Au interface exhibit easier lattice oxygen activation and higher intrinsic activity in catalyzing low‐temperature CO oxidation than the starting Au‐TiO2 interface. These results advance fundamental understanding of SMSI and demonstrate engineering of metal NP size and oxide facet as an effective strategy to tune the SMSI for efficient catalysis. [ABSTRACT FROM AUTHOR]

Strong metal–support interactions (SMSI) is an important concept in heterogeneous catalysis. Herein, we demonstrate that the Au‐TiO2 SMSI of Au/TiO2 catalysts sensitively depends on both Au nanoparticle (NP) sizes and TiO2 facets. Au NPs of ca. 5 nm are more facile undergo Au‐TiO2 SMSI than those of ca. 2 nm, while TiO2 {001} and {100} facets are more facile than TiO2{101} facets. The resulting capsulating TiO2−x overlayers on Au NPs exhibit an average oxidation state between +3 and +4 and a Au‐to‐TiO2−x charge transfer, which, combined with calculations, determines the Ti:O ratio as ca. 6:11. Both TiO2−x overlayers and TiO2−x‐Au interface exhibit easier lattice oxygen activation and higher intrinsic activity in catalyzing low‐temperature CO oxidation than the starting Au‐TiO2 interface. These results advance fundamental understanding of SMSI and demonstrate engineering of metal NP size and oxide facet as an effective strategy to tune the SMSI for efficient catalysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Catalytic performance of Ir/TiO 2 catalysts depended on the crystal plane of TiO 2. • Ir/TiO 2 -{1 0 1} catalyst gave 4-fold higher activity than that of Ir/TiO 2 -{0 0 1} catalyst. • The defects sites of TiO x support were responsible for the formation of crotyl alcohol. • Ir-TiO x interfacial sites may account for the formation of 1-butanol. Supported Ir/TiO 2 catalysts with the anatase TiO 2 nanocrystals exposing {1 0 1}, {1 0 0} and {0 0 1} planes were tested for selective hydrogenation of crotonaldehyde. The Ir/TiO 2 -{1 0 1} catalyst dominantly exposing {1 0 1} plane gave a initial reaction rate of 166.1 μmol g Ir -1 s−1 at 80 °C and a turnover frequency of crotyl alcohol formation of 0.022 s−1, which is 5 and 7 times respectively higher than those obtained on the Ir/TiO 2 -{0 0 1} catalyst dominantly exposing {0 0 1} plane even though they have similar Ir particle sizes (ca. 1.3 nm). The reaction behaviors were related to the surface oxygen vacancy, which served as surface acid sites and provide adsorption sites for C O bond in the CRAL molecule. Therefore, the higher concentration of oxygen vacancy in the Ir/TiO 2 -{1 0 1} accounted for the improved performance compared to the Ir/TiO 2 -{0 0 1}. However, strong adsorption of crotonaldehyde and/or products on the catalyst surface, as well as the CO poisoning via decarbonylation of crotonaldehyde, were the main reasons for the catalyst deactivation. [ABSTRACT FROM AUTHOR]

CuOx/TiO2 nanocatalysts (x=0 or 1) with ∼11 % wt. Cu loading employing TiO2 nanocrystals with various morphologies predominantly exposing {001}, {100}, and {101} facets as supports have been synthesized as catalysts for CO oxidation with excess of O2 (oxidative atmosphere) and water gas shift (WGS) reaction (reductive atmosphere). Strong TiO2 morphology effects were observed. The strongest Cu2O−TiO2 interaction was observed in CuO−TiO2{001} nanocatalyst, while the strongest Cu‐TiO2 interaction occurred in Cu‐TiO2{100} nanocatalyst. Catalytic activities of various CuO/TiO2 nanocatalysts in CO oxidation and of various Cu/TiO2 nanocatalysts in WGS reaction follow the same order of CuOx/TiO2{100}>CuOx/TiO2{101}>CuOx/TiO2{001}, and all CuO/TiO2 nanocatalysts are stable in CO oxidation but all Cu/TiO2 nanocatalysts suffer from serious deactivation in WGS reaction. The active structure of CuO/TiO2 nanocatalysts in CO oxidation was found to be the CuO species, while the active structure of Cu/TiO2 nanocatalysts in WGS reaction to be the Cu‐TiO2 interface which is relevant to the Cu‐TiO2 interaction. The supported Cu nanoparticles in Cu/TiO2 nanocatalysts tend to agglomerate at high temperatures in 5 %CO/Ar atmosphere, responsible for the deactivation in WGS reaction. These results not only demonstrate the morphology‐dependent CuOx‐TiO2 interaction in CuOx/TiO2 nanocatalysts, but also reveal reaction‐dependent active structures of CuOx/TiO2 nanocatalysts. [ABSTRACT FROM AUTHOR]

Here we report a new method for controlling photo-deposited metal nanoparticle size by manipulating surface defect structures of TiO2 nanocrystals. Our results demonstrate that the isolated oxygen vacancy could serve as an electron trapper while the oxygen vacancy cluster could act as an electron–hole recombination site in the photo-deposition process. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ir – TiO 2 interaction was dependent on Ir sizes and crystal plane of TiO 2. • Both activity and selectivity of the catalysts increased as the Ir size grew from single atom to nanoparticle. • End-on C O adsorption of crotonaldehyde was favored at the Ir-TiO x interface for Ir nanoparticles. • Crotonaldehyde adsorption geometry depends on H coverage on the catalyst surface. For the supported catalysts for the selective hydrogenation of α, β - unsaturated aldehyde with H 2 , tailoring of metal - support interfacial effect to improve reaction performance is a significant but challenging subject. In this work, we regulated both the size regimes of the Ir deposits (single atom, nanocluster and nanoparticle) and the crystal plane of anatase TiO 2 (TiO 2 (1 0 1), TiO 2 (1 0 0) and TiO 2 (0 0 1)) so as to alter the Ir-TiO x interfacial properties, in order to unravel reaction mechanism of selective hydrogenation of crotonaldehyde over the Ir/TiO 2 catalysts. Both the activity and selectivity to crotyl alcohol increased as the Ir size grew from single atom to nanoparticle, ascribed to high Ir0 content, high concentration of surface defects and prominent H-spillover effect on the Ir nanoparticles. Moreover, the in situ Fourier transform infrared spectroscopy (FTIR) and density functional theory (DFT) calculations demonstrated that an end-on C O adsorption mode for crotonaldehyde molecule was favored at the Ir-TiO x interface particularly at high H coverage, which thus facilitated the hydrogenation of C O bond to form crotyl alcohol. Moreover, the highest reactivity of the Ir nanoparticles was evidenced by the lowest reaction barrier. These results explicitly demonstrate that larger metal nanoparticles and adsorption geometry of the reactant at the metal - support interface are vital for improved catalytic performance, which would shed light on the ingenious catalyst design. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pd/TiO 2 {100} is highly active and stable for CO 2 hydrogenation into formate. • The activity is benefit from the moderate basic site and metallic Pd species. • Higher density of moderate basicity over Pd/TiO 2 {100} favors for CO 2 activation. • More metallic Pd species over Pd/TiO 2 {100} contributes to H 2 activation. • The stability is benefit from strong Pd-TiO 2 interactions. • The oxygen vacancy in the TiO 2 {100} promote the Pd-TiO 2 interactions. Pd supported on different anatase TiO 2 nanocrystals predominantly exposing either {1 0 0}, {1 0 1}, or {0 0 1} facets were tested for CO 2 hydrogenation into formate. Remarkable morphology-dependent catalysis was observed. Compared to 2%Pd/TiO 2 {1 0 1} and 2%Pd/TiO 2 {0 0 1} catalysts, 2%Pd/TiO 2 {1 0 0} is highly active and stable, affording an unprecedented turnover frequency of ca. 1369 h−1 and keeping stable after 6 cycles at 313 K. This can be associated with, on the one hand, higher density of moderate basic site and relatively more Pd(0) species over 2%Pd/TiO 2 {1 0 0} contribute to the activations of CO 2 and H 2 , respectively, favorable for the activity; On the other hand, higher oxygen vacancy concentrations in the TiO 2 {1 0 0} promote the Pd-TiO 2 interactions and result in the formation and stability of flat Pd particles over 2%Pd/TiO 2 {1 0 0}, beneficial to the stability. These results highlight the importance of oxide morphology in formate formation and open up possibilities of oxide morphology engineering for developing efficient Pd-based catalysts for CO 2 hydrogenation. [ABSTRACT FROM AUTHOR]

Gram-positive enhancer matrix (GEM) nanoparticles are often used in mucosal immunity, preparation of subunit vaccines or as an immune adjuvant due to its good immunological activities in recent years. Here, we designed and screened out a high affinity peptide ligand PL23, which could specifically target the non-epitope region of Classic Swine Fever Virus (CSFV) E2 protein, by virtual screening technology, enzyme linked immunosorbent assay (ELISA) and surface plasmon resonance (SPR) test. The OD value of PL23 at 450 nm was reached 1.982, and the K D value of it was 90.12 nM. Its binding capacity to protein was verified by SDS-PAGE as well. PL23 was subsequently conjugated to GEM nanoparticles by dehydration synthesis generating GEM-PL23 particles, and the GEM-PL-E2 particles were assembled after incubated with CSFV E2 protein. The cytotoxic test indicated that PL23, CSFV E2 protein, GEM nanoparticles, GEM-PL23 particles and GEM-PL-E2 particles were not toxic to cells and GEM nanoparticles could significantly promote the growth of APCs at high concentration for 1 h, p<0.001. In addition, GEM nanoparticles could promote the uptake of antigen by APCs. The cytokines tests suggested that GEM-PL-E2 particles could promote innate immune responses, regulate adaptive immune responses generated by T cells and APCs, and promote the differentiation and maturation of dendritic cells without producing inflammasomes. The results of immunological activity identification showed GEM-PL-E2 particles induced higher levels of both neutralizing antibodies and anti-CSFV antibodies than CSFV E2 protein in mice. This strategy provided a new, simpler, faster and cheaper method for assembling GEM nanoparticles, using an affinity peptide ligand replaced the protein anchor (PA), and provided a better application prospect for the application of GEM particles. [ABSTRACT FROM AUTHOR]

Various supported Ir/TiO2 catalysts were prepared using different Ir precursors (i.e., H2IrCl6, (NH4)2IrCl6 and Ir(acac)3) and tested for vapor phase selective hydrogenation of crotonaldehyde. The choice of Ir precursor significantly altered the Ir-TiOx interaction in the catalyst, which thus had essential influences on the geometric and electronic properties of the Ir species, reducibility, and surface acidity, and, consequently, their reaction behaviors. The Ir/TiO2-N catalyst using (NH4)2IrCl6 as the precursor gave the highest initial reaction rates and turnover frequencies of crotyl alcohol formation. Such high performance was ascribed to the high Ir dispersion and high surface concentration of Ir0 species, as well as a higher surface acidity, in the Ir/TiO2-N catalyst compared to its counterparts, indicating the synergistic roles of the Ir-TiOx interface in the reaction, as the interfacial sites were responsible for the adsorption/activation of H2 and the C=O bond in the crotonaldehyde molecule. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Pd-CeO 2 interaction is related to the oxygen vacancy concentration in the CeO 2. • Higher oxygen vacancy concentration in Pd/r-CeO 2 results in higher content of Pd2+ species. • The highest content of metallic Pd species in Pd/p-CeO 2 accounts for the best activity. • Hydrogenation of bidentate carbonate and bicarbonate species is the rate determining step. Several Pd catalysts supported on CeO 2 with different morphologies (i.e. CeO 2 rods (r-CeO 2), cubes (c-CeO 2) and polyhedra (p-CeO 2)) were tested for the CO 2 hydrogenation into formate. Remarkable morphology - dependent Pd-CeO 2 interaction was observed, which was related to the oxygen vacancies in the CeO 2. The r-CeO 2 with the highest concentration of oxygen vacancy resulted in smaller Pd particles and more positively-charged Pd species in the Pd/r-CeO 2 catalyst. The best performance was obtained over the Pd/p-CeO 2 catalyst, giving a turnover frequency of 746 h−1 at 40 °C. The enhanced activity was due to the highest content of metallic Pd species in the catalyst, which was responsible for the facile activation of H 2. Moreover, in situ spectroscopic results revealed that the hydrogenation of the carbonaceous intermediates was the rate - determining step. This work demonstrates oxide morphology engineering as a powerful strategy in developing efficient Pd - based catalysts for CO 2 hydrogenation. [ABSTRACT FROM AUTHOR]

DPL (http://www.peptide-ligand.cn/) is a comprehensive database of peptide ligand (DPL). DPL1.0 holds 1044 peptide ligand entries and provides references for the study of the polypeptide platform. The data were collected from PubMed-NCBI, PDB, APD3, CAMPR3, etc. The lengths of the base sequences are varied from 3 to78. DPL database has 923 linear peptides and 88 cyclic peptides. The functions of peptides collected by DPL are very wide. It includes 540 entries of antiviral peptides (including SARS-CoV-2), 55 entries of signal peptides, 48 entries of protease inhibitors, 45 entries of anti-hypertension, 37 entries of anticancer peptides, etc. There are 270 different kinds of peptide targets. All peptides in DPL have clear binding targets. Most of the peptides and receptors have 3D structures experimentally verified or predicted by CYCLOPS, I-TASSER and SWISS-MODEL. With the rapid development of the COVID-2019 epidemic, this database also collects the research progress of peptides against coronavirus. In conclusion, DPL is a unique resource, which allows users easily to explore the targets, different structures as well as properties of peptides. [ABSTRACT FROM AUTHOR]

In this study, we report the desirable conversion of H 2 O 2 to OH with aquifer sediment activated by ascorbic acid. Although aquifer sediment contained various iron minerals, such as goethite, hematite, montmorillonite, muscovite, chlorite and phlogopite, it could not efficiently activate H 2 O 2 to produce OH. Interestingly, the presence of ascorbic acid dramatically promoted the OH conversion efficiency of H 2 O 2 by aquifer sediment to remediate organic contaminants in groundwater, which was ascribed to the efficient iron cycle of aquifer sediment induced by ascorbic acid. Among these minerals in sediment, goethite and hematite were more reactive than other minerals to activate H 2 O 2 in the presence of ascorbic acid. Although the initial pH could affect the OH conversion efficiency of H 2 O 2 , H 2 O 2 could be decomposed by aquifer sediment at pH 3–11 after the introduction of ascorbic acid. Along with the complete degradation of organic contaminants, the final pH of solution increased to 8.3, which was close to the initial pH (8.9) of groundwater. Moreover, packed column of aquifer sediment could also catalyze the H 2 O 2 conversion to OH for the removal of different organic contaminants with adding ascorbic acid, suggesting a new strategy for in situ chemical oxidation remediation of organic contaminated groundwater. [ABSTRACT FROM AUTHOR]

[Display omitted] • Evolutions of phase structure and surface structure of ZnO-ZrO 2 composite oxides are established. • Structure-activity relation of ZnO-ZrO 2 composite oxides in CO 2 hydrogenation reactions is demonstrated. • Bidentate formate is the key intermediate for CO 2 hydrogenation to methanol. • Carbonates are the key intermediates for CO 2 hydrogenation to CO. ZnO-ZrO 2 composite oxides are used as catalysts for CO 2 hydrogenation reaction. Herein, we prepare a series of ZnO-ZrO 2 composite oxides via co-precipitation method and comprehensively study their structural evolution and catalytic performance in CO 2 hydrogenation reaction. Via combined spectroscopic and microscopic characterization techniques, we found that, as the Zr content increased, phase structures of ZnO-ZrO 2 composite oxides evolved from the mixture of hexagonal ZnO phase and Zn-doped ZrO 2 solid solution phases to the pure Zn-doped ZrO 2 solid solution phase. Zn-doped ZrO 2 solid solution nanoparticles of mixed-phased ZnO-ZrO 2 composite oxides were observed to preferentially nucleate and grow within the bulk of ZnO nanoparticles. Surfaces of mixed-phased ZnO-ZrO 2 composite oxides are enriched with Zn, while the pure Zn-doped ZrO 2 solid solutions exhibit uniform bulk and surface compositions. ZnO-ZrO 2 composite oxides are much more catalytic active than pure ZnO, t-ZrO 2 and m-ZrO 2 in catalyzing CO 2 hydrogenation reactions. The pure Zn-doped ZrO 2 solid solution phase exhibit high selectivity toward CH 3 OH production, while pure ZnO, t-ZrO 2 , m-ZrO 2 and mixed-phased ZnO-ZrO 2 composite oxides exhibit high selectivity toward CO production. Bidentate formate species and carbonates/bicarbonates species are the key intermediates of the CO 2 hydrogenation to methanol and CO, respectively. These results deepen the fundamental understanding of structure–activity relation and reaction mechanisms for ZnO-ZrO 2 composite oxides-catalyzed CO 2 hydrogenation reaction. [ABSTRACT FROM AUTHOR]