While utilization of transitional metals as a promoter has been extensively studied to enhance the activity of Pt-based catalysts for the oxidation of formaldehyde (HCHO), there is still a lack of well elucidated property−function relationship for the rational selection of a promoter in catalyst design. Herein, we modified a Pt/ CeO 2 catalyst with two transitional metal dopants (i.e., Mn and Cu) that showed negligible influence on the physical structure of the Pt− CeO 2 matrix but distinct effects on the activity of the catalyst. Complementary characterizations combined with density functional theory modeling revealed that the transitional metal dopants significantly modified the electronic structure of the catalyst and shifted the d-band of Pt to higher energy with different extents, which may tune the bonding strength of HCHO/intermediates with the Pt−CeO 2 interface domain. The catalyst with moderate bonding strength (i.e., Pt−Mn/CeO 2 ) displayed the highest reactivity under the ambient condition, while Pt−Cu/CeO 2 with the highest bonding strength showed a dramatically decreased activity. No correlation was observed between the abundancy of the active oxygen and catalytic activity, likely due to the oxygen supply having a much higher rate than the rate-determining step. This work contributes to the elucidation about the property−function relationship of a transitional metal dopant in Pt-based catalysts for the oxidation of HCHO.

Urban building reconstruction is an important step for urban digitization and realisticvisualization. In this paper, we propose a novel automatic method to recover urban building geometry from 3D point clouds. The proposed method is suitable for buildings composed of planar polygons and aligned with the gravity direction, which are quite common in the city. Our key observation is that the building shapes are usually piecewise constant along the gravity direction and determined by several dominant shapes. Based on this observation, we formulate building reconstruction as an energy minimization problem under the Markov Random Field (MRF) framework. Specifically, point clouds are first cutinto a sequence of slices along the gravity direction. Then, floorplans are reconstructed by extracting boundaries of these slices, among which dominant floorplans are extracted and propagated to other floors via MRF. To guarantee correct propagation, a new distance measurement for floorplans is designed, which first encodes floorplans into strings and then calculates distances between their corresponding strings. Additionally, an image based editing method is also proposed to recover detailed window structures. Experimental results on both synthetic and real data sets have validated the effectiveness of our method.

Fine regulation of interface phase and electronic structure is crucial for hydrogen evolution reaction (HER) in low-cost heterogeneous catalysts. Herein, we have successfully synthesized MoS2/CoS2 hetero-nanostructures with abundant 1T-MoS2 phase...

The progress of deep-blue perovskite light-emitting diodes (DB-PeLEDs) lags far behind their green and red counterparts due to the lack of stable DB perovskite materials. Here, a novel class of...

While C–O bond cleavage is pivotal in the depolymerization/valorization of lignin, it is still challenging to control the reaction selectivity under high activity due to the higher dissociation energy of aromatic C–O bonds relative to other reactions such as direct ring hydrogenation. Herein, we report the activation of Al2O3-supported earth-abundant MnO with embedded Ru to enhance the selective hydrogenolysis of aromatic C–O bonds in both a model compound and real lignin. Complementary characterizations demonstrate that the embedment of Ru into the MnO phase generates vacancy-enriched MnO under a hydrogen atmosphere, and such abundant active sites enable about threefold enhancement of the specific reaction rate for C–O bond hydrogenolysis. Moreover, the defective MnO overlayer on Ru nanoparticles has a stronger interaction with the O in diphenyl ether with preferential vertical adsorption, which inhibits the activation and hydrogenation of the aromatic ring, leading to higher selectivity for direct C–O bond cleavage. In the depolymerization of real lignin, the bimetallic Ru–MnO shows significantly higher (fivefold) activity than monometallic Ru under the tested condition. This work provides a general framework for the rational design of highly efficient catalysts for selective C–O bond cleavage.

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