Enhancing Compatibility of Two-Step Tandem Catalytic Nitrate Reduction to Ammonia Over P-Cu/Co(OH).

Electrochemical nitrate reduction reaction (NORR) is a promising approach to realize ammonia generation and wastewater treatment. However, the transformation from NO to NH involves multiple proton-coupled electron transfer processes and by-products (NO , H, etc.), making high ammonia selectivity a challenge.

Strain-Driven Phase Transitions in Delafossite CuAAlO: A Key to Enhanced Photo(electro)catalytic Performance.

This study investigates the impact of intrinsic strain and phase transitions on the thermodynamic stability and electronic properties of CuAAlO solid solutions, which are key to their photocatalytic performance. It is demonstrated that CuAAlO with A = Ag, Au, Pt can form continuous isostructural solid solutions due to relatively small compressive strain, while a substantial increase strain restricts CuPdAlO to forming only limited solutions. For A = Li, Na, the formation of heterostructural solid solutions is facilitated by structural motif alterations, accommodating significant differences in ionic radii and A-O bond characteristics.

Accelerated Charge Transfer through Interface Chemical Bonds in MoS/TiO for Photocatalytic Conversion of Lignocellulosic Biomass to H.

Solar photocatalytic H production from lignocellulosic biomass has attracted great interest, but it suffers from low photocatalytic efficiency owing to the absence of highly efficient photocatalysts. Herein, we designed and constructed ultrathin MoS-modified porous TiO microspheres (MT) with abundant interface Ti-S bonds as photocatalysts for photocatalytic H generation from lignocellulosic biomass. Owing to the accelerated charge transfer related to Ti-S bonds, as well as the abundant active sites for both H and OH generation, respectively, related to the high exposed edge of MoS and the large specific surface area of TiO, MT photocatalysts demonstrate good performance in the photocatalytic conversion of α-cellulose and lignocellulosic biomass to H.

Changeable Active Sites by Pr Doping CuSA-TiO Photocatalyst for Excellent Hydrogen Production.

Photocatalytic water splitting for clean hydrogen production has been a very attractive research field for decades. However, the insightful understanding of the actual active sites and their impact on catalytic performance is still ambiguous. Herein, a Pr-doped TiO-supported Cu single atom (SA) photocatalyst is successfully synthesized (noted as Cu/Pr-TiO).

Tuning electronic structure for enhanced photocatalytic performance: theoretical and experimental investigation of CuMM'O (M, M' = B, Al, Ga, In) solid solutions.

This study introduces robust screening methodology for the efficient design of delafossite CuMM'O solid-solution photocatalysts using band-structure engineering. The investigation not only reveals the formation rules for various CuMM'O solid solutions but also highlights the dependence on both lattice compatibility and thermodynamic stability. Moreover, the study uncovers the nonlinear relationship between composition and band gaps in these solid solutions, with the bowing coefficient determined by the substitution constituents.

A Bi-Co Corridor Construction Effectively Improving the Selectivity of Electrocatalytic Nitrate Reduction toward Ammonia by Nearly 100.

Improving the selective ammonia production capacity of electrocatalytic nitrate reduction reaction (NO RR) at ambient conditions is critical to the future development and industrial application of electrosynthesis of ammonia. However, the reaction involves multi-proton and electron transfer as well as the desorption and underutilization of intermediates, posing a challenge to the selectivity of NO RR. Here the electrodeposition site of Co is modulated by depositing Bi at the bottom of the catalyst, thus obtaining the Co+Bi@Cu NW catalyst with a Bi-Co corridor structure.

Gram-scale solvothermal synthesis of Fe-doped CuCoO nanosheets and improvement of the oxygen evolution reaction performance.

In this work, we used Cu-BTC-IPA and Co(NO)·6HO as precursors to synthesize CuCoO (CCO) nanocrystals with a suitable crystal phase, morphology and high yield by changing the process parameters, such as reactant concentration, reactant ratio, mineralizer dosage, and the type of polyvinylpyrrolidone surfactant. In addition, the effects of different concentrations (1 at%, 3 at%, 5 at%) of Fe doping on the crystal structure and oxygen evolution reaction (OER) performance of CCO were studied. The experimental results show that Fe ions are uniformly doped into the lattice to replace the A-site (Cu) position, which not only reduces the grain size of CCO, but also increases its specific surface area.

Comparative Analysis of the Interfacial Structure and Properties of BiOX/BiOY (X, Y = F, Cl, Br, and I) Heterostructures through DFT Calculations.

This study focuses on the systematic investigation of the microstructure, interfacial energy, and electronic structure of six BiOX/BiOY heterostructures constructed using four bismuth oxyhalide materials. Utilizing density functional theory (DFT) calculations, the study provides fundamental insights into the interfacial structure and properties of these heterostructures. The results indicate that the formation energies of BiOX/BiOY heterostructures decrease in the order of BiOF/BiOI, BiOF/BiOBr, BiOF/BiOCl, BiOCl/BiOBr, BiOBr/BiOI, and BiOCl/BiOI.

Stability and fundamental properties of Cu O as optoelectronic functional materials.

Binary Cu O compounds have some advantages as optoelectronic functional materials, but their further development has encountered some bottlenecks, such as inaccurate bandgap values and slow improvement of photoelectric conversion efficiency. In this work, all possible stoichiometric ratios and crystal structures of binary Cu O compounds were comprehensively analyzed based on a high-throughput computing database. Stable and metastable phases with different stoichiometric ratios were obtained.

Rational Design of a Two-Dimensional Janus CuFeO Single Layer as a Photocatalyst and Photoelectrode.

The exfoliation of 2D nanomaterials from 3D multimetal oxides with a stable structure is a great challenge. Herein, a delafossite CuFeO nanosheet becomes an open-layered structure by introducing excess oxygen so that the 2D Janus CuFeO single layer can be further obtained by aqueous ultrasonic exfoliation. The 2D Janus CuFeO single layer breaks the limitation of mirror symmetry, which is very beneficial to the effective separation of photogenerated electron-hole pairs.

Effect of Ag alloying and trace precipitation on corrosion resistance of Ti-Ta-Ag ternary alloy.

This work systematically analysed the electrochemical and corrosion behaviour of Ti-Ta-Ag ternary alloy samples in Hank's solution. For the samples with 1.5% and 3% Ag content, the sintering temperature increased from 750 to 950°C, and the corresponding corrosion resistance increased by 100 times due to the increased alloying of Ag; meanwhile for the sample with 4.

Role of the Polar Electric Field in Bismuth Oxyhalides for Photocatalytic Water Splitting.

The built-in electric field generated by polar materials is one of the most effective strategies to promote the separation of photogenerated electron-hole pairs in the field of photocatalysis. However, because of the complexity and diversity of the built-in electric field in polar materials, it is not clear how to enhance the photocatalytic performance and how to control the polar electric field effectively. To this end, four-layered bismuth oxyhalides, BiOX, and BiOXO (X = Br, I) were synthesized by a simple hydrothermal method.

DFT calculations for single-atom confinement effects of noble metals on monolayer g-CN for photocatalytic applications.

Graphitic carbon nitride, as a very promising two-dimensional structure host for single atom catalysts (SACs), has been studied extensively due to its significant confinement effects of single atoms for photocatalytic applications. In this work, a systematic investigation of g-CN confining noble metal single atoms (NM@g-CN) will be performed by using DFT calculations. The geometric structure calculations indicate that the most favorable anchored sites for the NM is located in the six-fold cavity, and the deformed wrinkle space of g-CN helps the NM to be stabilized in the six-fold cavity.

Study of Ag precipitation and mechanical properties of Ti-Ta-Ag ternary alloy.

Ti-25Ta-Ag alloy samples with different content of Ag were prepared by spark plasma sintering method. X-ray diffraction, microscopic metallographic, scanning electron microscopy, and transmission electron microscopy were used to analyze the phase structure and morphology of the alloy samples. Ti-Ta-Ag can form a stable ternary alloy system.

Effects of the Preparation Process on the Photocatalytic Performance of Delafossite CuCrO.

Hydrothermal and solid-state reaction methods are commonly used to prepare the delafossite CuCrO photocatalyst. It has been reported that the photocatalytic performances of CuCrO samples prepared by these methods are quite different. In order to explore the possible influence of different preparation processes on the photocatalytic performance and the corresponding improvement strategies, this work compares the microstructure and physicochemical properties of the samples prepared by these two methods on the basis of optimizing the process conditions.

Mildly regulated intrinsic faradaic layer at the oxide/water interface for improved photoelectrochemical performance.

Metal oxides are widely used in different fields, including photoelectrocatalysis, photocatalysis, dye-sensitized solar cells, photoinduced superhydrophilicity and so on. It is well-known that there are intrinsic hydrated layers on the surfaces of metal oxides in ambient air or the electrolyte. Generally, interface layers between metal oxides and solutions have significant effects on the performances in these applications.

Spontaneous Polarization Effect and Photocatalytic Activity of Layered Compound of BiOIO.

Internal polarized electric field is found to be an effective and available strategy to separate photogenerated electron-hole pairs. By this method, the efficiency of photocatalytic reactions can be obviously enhanced. Here, the layered compound of BiOIO with spontaneous polarization was synthesized by a simple hydrothermal method.

A High-Throughput Study of the Electronic Structure and Physical Properties of Short-Period (GaAs)(AlAs) (m, n ≤ 10) Superlattices Based on Density Functional Theory Calculations.

As important functional materials, the electronic structure and physical properties of (GaAs)(AlAs) superlattices (SLs) have been extensively studied. However, due to limitations of computational methods and computational resources, it is sometimes difficult to thoroughly understand how and why the modification of their structural parameters affects their electronic structure and physical properties. In this article, a high-throughput study based on density functional theory calculations has been carried out to obtain detailed information and to further provide the underlying intrinsic mechanisms.

Effects of crystal structure and composition on the photocatalytic performance of Ta-O-N functional materials.

For photocatalytic applications, the response of a material to the solar spectrum and its redox capabilities are two important factors determined by the band gap and band edge position of the electronic structure of the material. The crystal structure and composition of the photocatalyst are fundamental for determining the above factors. In this article, we examine the functional material Ta-O-N as an example of how to discuss relationships among these factors in detail with the use of theoretical calculations.

Systematic studies on Yb Bi VO:Tm solid solutions: experiments and DFT calculations on up-conversion photoluminescence properties.

Compound solid solutions have attracted intensive attention due to their adjustable structure, electronic structure, and optical properties. Despite tremendous advances in compound solid solution preparations, combining a rare metal compound and a bismuth compound with the same crystal phase by forming a compound solid solution is still challenging but fascinating. For example, RE Bi VO with a zircon-type structure exhibits tunable band gaps and photoluminescence performance with varying RE compositions.

Investigation of energy band alignments and interfacial properties of rutile NMO/TiO (NM = Ru, Rh, Os, and Ir) by first-principles calculations.

In the field of photocatalysis, constructing hetero-structures is an efficient strategy to improve quantum efficiency. However, a lattice mismatch often induces unfavorable interfacial states that can act as recombination centers for photo-generated electron-hole pairs. If the hetero-structure's components have the same crystal structure, this disadvantage can be easily avoided.

Density functional theory study on the metal-support interaction between a Au cluster and an anatase TiO(001) surface.

Noble metals supported on TiO surfaces have shown extraordinary photocatalytic properties in many important processes such as hydrogenation, water splitting, degradation of hazards, and so on. Using density functional theory calculations, this work has systematically investigated the microstructure and electronic structure of three different Au isomers loaded on anatase TiO(001) surface. The calculated results show that the interaction between the Au cluster and the TiO support is closely related to the adsorption site and the stability of the Au cluster in the gas phase.

Series of ZnSn(OH) Polyhedra: Enhanced CO Dissociation Activation and Crystal Facet-Based Homojunction Boosting Solar Fuel Synthesis.

A series of ZnSn(OH) polyhedra are successfully explored with well-controlled area ratio of the exposed {100} and {111} facets. Band alignment of the exposed facet-based homojunction of the elegant polyhedron facilitates spatial separation of photogenerated electrons and holes on {111} and {100} surfaces, respectively. Optimal area ratio of {100} to {111} is the prerequisite for pronounced CO photocatalytic performance of high-symmetry cuboctahedra into methane (CH).

DFT study on the interfacial properties of vertical and in-plane BiOI/BiOIO hetero-structures.

Composite photocatalysts with hetero-structures usually favor the effective separation of photo-generated carriers. In this study, BiOIO was chosen to form a hetero-structure with BiOI, due to its internal polar field and good lattice matching with BiOI. The interfacial properties and band offsets were focused on and analyzed in detail by DFT calculations.