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Cu-based nanocatalysts have been widely used for CO2 hydrogenation, but their poor stability is the bottleneck for further industrial applications. A high-performance and long-lived Cu/SiO2 nanocatalyst was synthesized by an ammonia-evaporation method for CO2 hydrogenation. The conversion of CO2 reaches up to 28%, which is close to the equilibrium conversion of CO2 (30%), and the selectivity to methanol is 21.3%, which is much higher than the equilibrium selectivity (6.6%) at 320 °C and 3.0 MPa. Furthermore, after 120 h of evaluation, the conversion can be still maintained at a high value (27%), which is much better than a Cu/SiO2 catalyst prepared by traditional impregnation. The Cu+ species has been demonstrated to be the active component for the activation and conversion of CO2. The higher ratio of Cu+/(Cu0 + Cu+) and interaction between the metal and support deriving from copper phyllosilicate are mainly responsible for the high catalytic activity and excellent stability, respectively.

In the present paper, preferentially oriented (111) Pt nanoparticles (mostly octahedral and tetrahedral, namely {111}Pt nanoparticles) have been characterized and compared with a Pt(554) single-crystal electrode as their voltammetric features are quite similar in 0.5 M H 2 SO 4 . The anion and Bi adsorption behaviours suggest that the {111}Pt nanoparticles contain relatively wide hexagonal domains and also isolated sites which could adsorb solely hydrogen. Bi step decoration has been successfully extended to modify the defects of {111}Pt nanoparticles without blocking terrace sites. CO charge displacement has been applied to determine the potential of zero total charge (pztc) of non-decorated and Bi decorated surfaces. It has found that the positive shift of pztc on defect-decorated {111}Pt nanoparticles is not so significant in comparison with that of Pt(554) due to the relative short mean length of (111) domains on the {111}Pt nanoparticles. CO stripping demonstrates that {111}Pt nanoparticles exhibit higher reactivity toward CO oxidation. This reflects the role of the defect sites in nanoparticles, evidenced by the disappearance of the ''pre-wave'' in the stripping voltammogram once the defects were blocked by Bi. The stripping peaks shift to higher potential on Bi decorated surfaces, indicating the active role of both steps and defects for CO oxidation. By comparing the CO stripping charge and the change in hydrogen adsorption charge of surfaces with and without Bi decoration, including reasonable deconvolution, the local CO coverage on defect and terrace sites were obtained for the first time for the {111}Pt nanoparticles, and the results are in good agreement with those obtained on Pt(554). Chronoamperometry studies show tailing in all current-time transients of CO oxidation on all surfaces studied. The kinetics of CO oxidation can be satisfactorily simulated by a modified LangmuirHinshelwood model, demonstrating that CO oxidation on all studied surfaces follows the same mechanism.

Tetrahexahedral Pt nanocrystals (THH Pt NCs) bounded by high-index facets possess a high density of active sites and display therefore a higher catalytic activity in comparison with those enclosed by low-index facets. In the current communication, we report, for the first time, the decoration of THH Pt NC surfaces by using Bi adatoms and have demonstrated that the catalytic activity of the Bi decorated THH Pt NCs toward HCOOH electrooxidation has been drastically enhanced in comparison with bare THH Pt NCs. It has also been revealed that the catalytic activity of Bi decorated THH Pt NCs for all coverages investigated always exhibits a higher catalytic activity that is about double that of Bi decorated Pt nanospheres. The study is of great importance regarding both fundamentals and applications.

We synthesized monodisperse Pd nanocrystals with exposed (111) and (100) facets through preferentially oriented facet growth technology. We then supported them on α-Al2O3 as catalysts for application in CO oxidative coupling to dimethyl oxalate (DMO) and find, for the first time, that the (111) facets of Pd nanocrystals are active planes for CO oxidative coupling to DMO. This conclusion is based on experiment results, reaction mechanism, and density functional theory calculation. Directed by this shape effect, a high-performance and long-lived nanocatalyst with much lower Pd load for CO oxidative coupling to DMO was successfully prepared by a new wet impregnation–solution chemical reduction method, which can well control the exposure of (111) facets and sizes of Pd nanocrystals.

Batteries using lithium (Li) metal as the anode are considered promising energy storage systems because of their high specific energy densities. The crucial bottlenecks for Li metal anode are Li dendrites growth and side reactions with electrolyte inducing safety concern, low Coulombic efficiency (CE), and short cycle life. Vinylene carbonate (VC), as an effective electrolyte additive in Li-ion batteries, has been noticed to significantly enhance the CE, whereas the origin of such an additive remains unclear. Here we use cryogenic transmission electron microscopy imaging combing with energy dispersive X-ray spectroscopy elemental and electron energy loss spectroscopy electronic structure analyses to reveal the role of the VC additive. We discovered that the electrochemically deposited Li metal (EDLi) in the VC-containing electrolyte is slightly oxidized with the solid electrolyte interphase (SEI) being a nanoscale mosaic-like structure comprised of organic species, Li2O and Li2CO3, whereas the EDLi formed in the VC-free electrolyte is featured by a combination of fully oxidized Li with Li2O SEI layer and pure Li metal with multilayer nanostructured SEI. These results highlight the possible tuning of crucial structural and chemical features of EDLi and SEI through additives and consequently direct correlation with electrochemical performance, providing valuable guidelines to rational selection, design, and synthesis of additives for new battery chemistries.

Polycyanometallate compounds with both photochromism and photomagnetism have appealing applications in optical switches and memories, but such optical behaviors were essentially restricted to the cryogenic temperature. We realized, for the first time, the photochromism and photomagnetism of 3d-4f hexacyanoferrates at room temperature (RT) in [Eu(III)(18C6)(H2O)3]Fe(III)(CN)6·2H2O (18C6 = 18-crown-6). Photoinduced electron transfer (PET) from crown to Fe(III) yields long-lived charge-separated species at RT in air in the solid state and also weakens the magnetic susceptibility significantly. The PET mechanism and changing trend of photomagnetism differ significantly from those reported for known 3d-4f hexacyanoferrates. This work not only develops a new type of inorganic-organic hybrid photochromic material but opens a new avenue for RT photomagnetic polycyanometallate compounds.

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