In this study, we summarize a series of typical 2D nanomaterials for photocatalytic CO2conversion. Furthermore, based on the characteristics of 2D materials and the current status of research on photocatalytic CO2reduction, the challenges and opportunities of 2D materials as prospective photocatalysts for CO2reduction will also be discussed.

Active, stable, and cost-effective electrocatalysts are attractive alternatives to the noble metal oxides that have been used in water splitting. The direct nucleation and growth of electrochemically active LDH materials on chemically modified MWCNTs exhibit considerable electrocatalytic activity toward oxygen evolution from water oxidation. CoMn-based and NiMn-based hybrids were synthesized using a facile chemical bath deposition method and the as-synthesized materials exhibited three-dimensional hierarchical configurations with tunable Co/Mn and Ni/Mn ratio. Benefiting from enhanced electrical conductivity with MWCNT backbones and LDH lamellar structure, the Co5Mn-LDH/MWCNT and Ni5Mn-LDH/MWCNT could generated a current density of 10 mA cm(-2) at overpotentials of ∼300 and ∼350 mV, respectively, in 1 M KOH. In addition, the materials also exhibited outstanding long-term electrocatalytic stability.

Kindlins play an important role in supporting integrin activation by cooperating with talin; however, the mechanistic details remain unclear. Here, we show that kindlins interacted directly with paxillin and that this interaction could support integrin αIIbβ3 activation. An exposed loop in the N-terminal F 0 subdomain of kindlins was involved in mediating the interaction. Disruption of kindlin binding to paxillin by structure-based mutations significantly impaired the function of kindlins in supporting integrin αIIbβ3 activation. Both kindlin and talin were required for paxillin to enhance integrin activation. Interestingly, a direct interaction between paxillin and the talin head domain was also detectable. Mechanistically, paxillin, together with kindlin, was able to promote the binding of the talin head domain to integrin, suggesting that paxillin complexes with kindlin and talin to strengthen integrin activation. Specifically, we observed that crosstalk between kindlin-3 and the paxillin family in mouse platelets was involved in supporting integrin αIIbβ3 activation and in vivo platelet thrombus formation. Taken together, our findings uncover a novel mechanism by which kindlin supports integrin αIIbβ3 activation, which might be beneficial for developing safer anti-thrombotic therapies.

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Hematite (α-Fe2O3) is one of the most promising candidates for photoelectrodes in photoelectrochemical water splitting system. However, the low visible light absorption coefficient and short hole diffusion length of pure α-Fe2O3 limits the performance of α-Fe2O3 photoelectrodes in water splitting. Herein, to overcome these drawbacks, single-crystalline tin-doped indium oxide (ITO) nanowire core and α-Fe2O3 nanocrystal shell (ITO@α-Fe2O3) electrodes were fabricated by covering the chemical vapor deposited ITO nanowire array with compact thin α-Fe2O3 nanocrystal film using chemical bath deposition (CBD) method. The J-V curves and IPCE of ITO@α-Fe2O3 core-shell nanowire array electrode showed nearly twice as high performance as those of the α-Fe2O3 on planar Pt-coated silicon wafers (Pt/Si) and on planar ITO substrates, which was considered to be attributed to more efficient hole collection and more loading of α-Fe2O3 nanocrystals in the core-shell structure than planar structure. Electrochemical impedance spectra (EIS) characterization demonstrated a low interface resistance between α-Fe2O3 and ITO nanowire arrays, which benefits from the well contact between the core and shell. The stability test indicated that the prepared ITO@α-Fe2O3 core-shell nanowire array electrode was stable under AM1.5 illumination during the test period of 40,000 s.

Laser Raman spectroscopy (LRS), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), ultraviolet and visible diffuse reflectance spectroscopy (UV-DRS), and temperature-programmed reduction (TPR) are used to characterize a series of WO 3 /CeO 2 samples. The results indicate that the dispersion capacity of tungsten oxide is about 4.8W 6+ ions nm -2 (CeO 2 ) and the structure of the supported tungsten oxide species is closely related to its loading amount on ceria. For the calcined samples, two distinctly different tungsten species have been identified by various methods. At low WO 3 loading, only the highly dispersed tungsten oxide species are found on the surface possibly formed by the incorporation of the dispersed W 6+ ions into the surface vacant sites of CeO 2 . Increasing the loading amount of tungsten oxide to a value above 4.8W 6+ ions nm -2 (CeO 2 ) leads to the formation of crystalline WO 3 . LRS and IR results of WO 3 /CeO 2 samples prepared by using different precursors have shown that calcination has a dramatic effect on the structure of the final product, which might mostly eliminate the differences of the precursors and result in final products with almost a same structure. TPR results of WO 3 / CeO 2 , CuO/CeO 2 , and CuO/WO 3 -CeO 2 samples reveal that the reduction behaviors of CuO dispersed on CeO 2 and on WO 3 premodified CeO 2 , i.e., WO 3 -CeO 2 , are apparently different. The result emphasizes the importance of the surface structure of the support on the properties of the dispersed metal oxide species; the conclusion is also supported by UV-DRS results. The coordination environments of the dispersed tungsten oxide and copper oxide species are discussed on the basis of the incorporation model (Chen, Y.; Zhang, L.

CuO/VO x /Ti 0.5 Sn 0.5 O 2 catalysts were prepared by an impregnation method and were tested on a NO þ CO model reaction. Both copper oxide and vanadium oxide can be highly dispersed on Ti 0.5 Sn 0.5 O 2 (denoted as TS, hereafter) support. The dispersed oxides form VÀOÀCu species when coexisting in the catalyst system. The formation of VÀOÀCu species renders the dispersed vanadium oxide aggregated and easier to be reduced; in contrast, the reduction temperature of dispersed copper oxide species is evidently higher than that without vanadium oxide (CuO/TS samples). The surface dispersed VÀOÀCu species are mainly the active component for the NO þ CO reaction. The activities of CuO/VO x /TS catalysts are highly dependent on the operating temperature and the amount of VÀOÀCu species. In the reaction atmosphere, NO molecules are adsorbed onto Cu 2þ sites, reduced V xþ (V 4þ or V 3þ ) sites, and even TS support, forming ÀNO and NO 3 À species. Adsorption of CO molecules proceeds only on Cu þ sites. The active species change with varying reaction temperature; hence, the NO þ CO reaction goes through different mechanisms at low and high temperatures over these catalysts.

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