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Broad absorption spectra with efficient generation and separation of available charge carriers are indispensable requirements for promising semiconductor-based photocatalysts to achieve the ultimate goal of solar-to-fuel conversion. Here, Cu3−xSnS4 (x = 0−0.8) with copper vacancies have been prepared and fabricated via solvothermal process. The obtained copper vacancy materials have extended light absorption from ultraviolet to near-infrared-II region for its significant plasmonic effects. Time-resolved photoluminescence shows that the vacancies can simultaneously optimize charge carrier dynamics to boost the generation of long-lived active electrons for photocatalytic reduction. Density functional theory calculations and electrochemical characterizations further revealed that copper vacancies in Cu3−xSnS4 tend to enhance hydrogen’s adsorption energy with an obvious decrease in its H2 evolution reaction (HER) overpotential. Furthermore, without any loadings, the H2 production rate was measured to be 9.5 mmol·h−1·g−1. The apparent quantum yield was measured to be 27% for wavelength λ > 380 nm. The solar energy conversion efficiency was measured to be 6.5% under visible-near infrared (vis-NIR) (λ > 420 nm).

Photocatalysis is considered a remarkable green method in the catalytic degradation of wastewater; however, the collection and loading of the powdered catalyst is still a problem. The traditional coating methods are usually unstable for the (photo-)degradation of organic binders. Herein, monolithic structures based on 2D–2D interactions instead of traditional 0D–0D and 1D–1D interactions were designed and constructed, realizing an interlocked structure with 3D active carbon fiber networks via the self-assembly of Bi2O2CO3 nanosheets (B-ACF) during the hydrothermal process. The loaded catalyst was further modified via an I-doping improvement strategy (4B-ACF-I), which exhibited 8 times the catalytic activity as compared to the intrinsic Bi2O2CO3. Thanks to the 3D monolithic and interlocked structure of loaded catalysts, B-ACF-I photocatalysts could be reused without any loss of catalytic activity during the cycling stability test. The expanded experiment and the removal of Cr(VI) under visible light prove that our improvement strategy can be considered even in actual wastewater treatment.

We report a facile method for dispersing Mn species onto two-dimensional Co3O4 nanosheets at the nanoscale for the selective catalytic reduction (SCR) of NOx with NH3. In comparison with the reference catalysts with higher Mn loadings, the Mn/Co3O4 (0.8 wt%) catalyst exhibits improved catalytic activity and a high H2O-resistance ability. Due to the strong interaction between cobalt and manganese oxides and the increased surface area of the Co3O4 nanosheets, the catalyst with an ultralow amount of Mn at the nanoscale possesses stronger reducibility, abundant Co3+ and surface oxygen species, which in turn enhance the NH3-SCR activity.

In this work, a catalyst of graphene oxide supported CeO2 (referred to as CeO2/GO) is prepared and characterized by TEM, H2-TPR, NH3-TPD and XPS. The catalytic tests show a NO conversion of 97% at ...

In the present work, O–functionalized carbon nanotubes (OCNTs) supported Pd–P nanoparticles (Pd–P/OCNTs) were prepared by using sodium hypophosphite (NaH 2 PO 2 ) as the P source and the reducing agent. The presence of O-functionalities on the carbon surface provide a microenvironment of the reaction system which favors the anchorage of P precursors and Pd salt ions through the electrostatic interaction and the formation of chemical bonds on the carbon support. Thus, Pd nanoparticles supported on the OCNTs could be efficiently incorporated with P. Pd with the modified outer electron structure enhanced the electrocatalytic performance for formic acid oxidation (FAO).

Herein, we report a facile method to prepare palladium nanoparticles (Pd NPs) anchored on nitrogen-doped carbon nanotubes (Pd/NCNTs) with particle size distribution uniformed. The Pd/NCNTs exhibits excellent ethanol oxidation reaction (EOR) mass activity of 2,489 A g−1, which is 5.1 times higher than commercial Pd/C. However, the anodic reaction of EOR suffers from poor efficiency and low durability. In order to solve the problem of low durability and have better understanding of the degradation mechanism of anodic catalysts, identical-location transmission electron microscopy (IL-TEM), X-ray photoelectron spectroscopy (XPS), and electrochemical measurements were carried out. These were applied to Pd/NCNTs catalyst under EOR in alkaline media. The results showed that the leaching of Pd NPs and the reduction of surface metallic Pd0 were the main reasons for the decreased EOR activity. These findings provide practical guidance for the development of catalysts with higher activity and stability for energy conversion.

The tunable photochromic systems have received wide attention in the photoelectronic fields. Herein, we report a diarylethene derivative attached with 2-hydrazylbenzothiazole via Schiff base, which shows the typical photochromic properties upon alternating irradiation with UV and visible light. Remarkably, the varying binding mode and complex strength between the diarylethene and selective metal ions (Cu2+, Ni2+, Cr3+, Sn2+ and Al3+) enable the methanol solution of the diarylethene to exhibit stepwise photochromic reactivity by virtue of these metal ions. The photochromic reactivity of the diarylethene could be suppressed at different levels by the formation of the complex with Cu2+ and Ni2+ in a 2:1 binding mode, respectively, whereas the photochromic reactivity was enhanced to varying degrees by Cr3+, Sn2+ and Al3+ in a 1:1 binding mode. Based on these multiple stimuli responses, a logic circuit with six input signals and three output signals was constructed to perform complex logical operations at the single molecular level.

In this work, palladium nanoparticles supported on 3D porous carbon frameworks (Pd/PCFs) were used in the selective hydrogenation of phenylacetylene. Catalytic tests conducted in a continuous-flow reactor coupled with theoretical calculations, HPLC and characterization methods helped to elucidate the structural origins of the observed selectivity patterns. A 62% selectivity towards styrene with a 93% conversion was observed in the hydrogenation of phenylacetylene at 20 °C and 3 bar for a hydrogen flow rate of 12 mL min−1 and a reaction liquid flow rate of 0.9 mL min−1. Commercially available Pd-based reference catalysts were tested under the same conditions in phenylacetylene hydrogenation, and the performance of 3 wt% Pd/PCFs was substantiated by studying the geometrical structure of PCFs and the stability of supported Pd nanoparticles under reaction conditions.

In the present study, Pd nanoparticles supported on phosphorus-incorporated porous carbon frameworks were prepared and used in selective phenylacetylene hydrogenation. The results showed that the interaction between Pd and the doped support affected the electron density and chemisorption properties of the Pd nanoparticles, and thus enhanced the catalytic performance for phenylacetylene hydrogenation.

Pd possesses higher activities than Pt for HCOOH oxidation as anode catalysts. However, because of the ease of Pd oxidation, the electrocatalytic stability of Pd is not satisfactory. Herein, low-loading Pd with high dispersions and narrow size distributions is nanosized on phosphorus-doped carbon nanotubes and applied as efficient anode catalysts for HCOOH oxidation. Surface analyses reveal that the decreased Pd3d electron density caused by electron transfer from Pd to P-doped CNTs enhances the HCOOH oxidation performance. Keywords: HCOOH oxidation, Carbon nanotubes, Phosphorus-doped, Anode catalysts, Low-loading palladium

In this work, the low-loading (3 wt%) palladium/graphene oxide (Pd/GO) aerogels are facilely prepared via the lyophilisation, vacuum and reduction treatments. The Pd/GO aerogels display enhanced activity and stability in comparison to the commercial Pd/C. The enhancement of electrocatalytic performance can be attributed to the functional groups on the surfaces of the GO support, such as carbonyl and carboxyl groups, which can be tuned to interact with palladium to form active phases for the reaction. In addition, Pd nanoparticles (NPs) remain dispersed in nanoscale on the reacted catalyst.

Palladium (Pd)-catalyzed selective hydrogenation of alkynes has been one of the most studied hydrogenation reactions in the last century. However, kinetic studies conducted to reveal the catalyst's active centers have been hindered because of dynamic surface changes on Pd during the reaction. In the present study, bimetallic Pd-Au nanoparticles supported on carbon nanotubes have been synthesized at room temperature as catalysts for selective hydrogenation of phenylacetylene, which show effectively enhanced selectivity compared to their monometallic counterparts. Structural and surface analyses of fresh and reacted catalysts reveal that selective hydrogenation of phenylacetylene is favored over nanosized Pd-Au bimetallic phases due to modifications in the Pd surface in terms of neighboring site isolation and electron density reduction.

As a modified configuration of the conventional anaerobic/anoxic/aerobic (AAO) process, a novel anoxic/anaerobic/aerobic (Reversed AAO, RAAO) process has been extensively applied in domestic wastewater treatment plants (WWTP). In this study, the Activated Sludge Model No. 2d (ASM2d) and a secondary clarifier model were calibrated and applied to simulate a pilot-scale RAAO test and evaluate the operational performance of the RAAO process. For calibration of the biological model ASM2d, only four kinetic parameters were adjusted to accurately simulate in-process variations of ammonium, nitrate and phosphate. Simulation results by the calibrated model demonstrated that phosphorus accumulating organisms (PAO) in the RAAO process (0.243 gP·(gCOD)−1) contains less poly-phosphate than the AAO process (0.266 gP·(gCOD)−1). With the increasing mixed liquor recirculation ratio in the RAAO process, the fraction of heterotrophic biomass and autotrophic biomass both increased, whereas the PAO decreased owing to adverse effects of electron acceptors on phosphorus release and poly-hydroxy-alkanoates synthesis.