Layered Nanocomposite 2D-TiO2 with Cu2O Nanoparticles as an Efficient Photocatalyst for 4-Chlorophenol Degradation and Hydrogen Evolution

Topics in Catalysis - New composites formed by layered hybrid TiO2(stearic acid) (LHTiO2) and, Cu2O nanoparticles were studied as photocatalysts that extend the response range to light visible for...     

MoS2@CP纳米片制备及其电催化产氢性能的研究

MoS2由于其优越的电催化产氢性能而引起关注,由于团聚和电导性较差导致其催化性能被阻碍.研究了碳纸上垂直生长的MoS2纳米片.通过水热和高温碳化的方法合成了MoS2@CP纳米片.合成的MoS2@CP提高了MoS2电导率,减少了坍塌,从而提高了其电催化性能.MoS2@CP的塔菲尔斜率为73.74 mV/dec,起始电压为77.9 mV,电流密度为10 mA·cm-2时的过电压为-118.6 mV,经过1000次循环,在0.5 mol/LH2SO4中,MoS2@CP具有优越的稳定性.     

Enhanced the Synergistic Effect of Tetracycline Adsorption and Photocatalytic Degradation on a Mesoporous Carbon Nitride

Journal of Inorganic and Organometallic Polymers and Materials - A mesoporous g-C3N4 with guanidine hydrochloride as precursor was prepared by molten salt assisted hard template of silica (SiO2)...     

Nanoscale Zero-Valent Iron Supported on Carbon Nitride as a Peroxymonosulfate Activator for the Efficient Degradation of Paraxylene

Catalysis Letters - Nanoscale zero-valent iron (nZVI) supported on polymeric graphitic carbon nitride (CN) composite (nZVI@CN) was synthesized via liquid phase reduction method as peroxymonosulfate...     

Characterization and Evaluation of Copper Slag as a Bifunctional Photocatalyst for Alcohols Degradation and Hydrogen Production

Topics in Catalysis - With the goal of providing an economically viable method for reducing water pollution and health impact by the mezcal industry wastes, photocatalytic degradation of toxic...     

In-Situ Preparation of Black TiO2/Cu2O/Cu Composites as an Efficient Photocatalyst for Degradation Pollutants and Hydrogen Production

Catalysis Letters - In the present work, non-precious Cu2O and Cu loaded hydrogenated black TiO2 nanoparticles were prepared, and the H2 evolution and the removal of a waterbased organic pollutant...     

Hydroxy Acid-Assisted Synthesis of Highly Dispersed Ni-NiS on CdS as Effective Photocatalyst for Hydrogen Evolution

To achieve the well-dispersed Ni–NiS dual-cocatalysts anchored CdS, the samples have been successfully constructed by a cheap and convenient method of hydroxy acid assisted hydrothermal method. Based on the coordination and reduction effects of hydroxy acids, Ni²⁺ can be facilely transformed into the high dispersed dual-function sites of Ni⁰ electrons trap and NiS holes reservoir. The highly dispersed Ni–NiS dual-cocatalysts not only provide more dual-function active sites but also present distinctly enhanced visible light absorption, effectively separated electron hole pairs and quickly migrated charge carriers. The optimized Ni–NiS/CdS–CA presented an excellent photocatalytic H₂ generation rate of 57.88 mmol·h^?1·g^?1, which is about 15.35 times higher than that of NiS/CdS. Moreover, the stability can be distinctly increased by modulating the surface cover of Ni–NiS with a suitable Ni/(Ni?+?Cd) atomic ratio. This work would provide a unique strategy to design the high effective photocatalysts with high dispersed bi-function dual cocatalysts.

Graphic Abstract

The well-dispersed Ni-NiS dual-cocatalysts anchored CdS in situ have been successfully constructed via the coordination and reduction effects of hydroxy acid assisted hydrothermal method. Ni-NiS/CdS-CA not only presents dual-function active sites but also exhibits distinctly enhanced visible light absorption, effectively separated electron hole pairs and quickly migrated charge carriers, resulting in a remarkable enhancement in photocatalytic H2 evolution activity.

     

Non-Metal-Doped Porous Carbon Nitride Nanostructures for Photocatalytic Green Hydrogen Production

Photocatalytic green hydrogen (H₂) production through water electrolysis is deemed as green, efficient, and renewable fuel or energy carrier due to its great energy density and zero greenhouse emissions. However, developing efficient and low-cost noble-metal-free photocatalysts remains one of the daunting challenges in low-cost H₂ production. Porous graphitic carbon nitride (gCN) nanostructures have drawn broad multidisciplinary attention as metal-free photocatalysts in the arena of H₂ production and other environmental remediation. This is due to their impressive catalytic/photocatalytic properties (i.e., high surface area, narrow bandgap, and visible light absorption), unique physicochemical durability, tunable electronic properties, and feasibility to synthesize in high yield from inexpensive and earth-abundant resources. The physicochemical and photocatalytic properties of porous gCNs can be easily optimized via the integration of earth-abundant heteroatoms. Although there are various reviews on porous gCN-based photocatalysts for various applications, to the best of our knowledge, there are no reviews on heteroatom-doped porous gCN nanostructures for the photocatalytic H₂ evolution reaction (HER). It is essential to provide timely updates in this research area to highlight the research related to fabrication of novel gCNs for large-scale applications and address the current barriers in this field. This review emphasizes a panorama of recent advances in the rational design of heteroatom (i.e., P, O, S, N, and B)-doped porous gCN nanostructures including mono, binary, and ternary dopants for photocatalytic HERs and their optimized parameters. This is in addition to H₂ energy storage, non-metal configuration, HER fundamental, mechanism, and calculations. This review is expected to inspire a new research entryway to the fabrication of porous gCN-based photocatalysts with ameliorated activity and durability for practical H₂ production.     

Sulfurized Co-Mo Alloy Thin Films as Efficient Electrocatalysts for Hydrogen Evolution Reaction

Catalysis Letters - Here, we successfully fabricated sulfurized Co-Mo alloy thin film electrodes with different compositions and studied their catalytic properties for hydrogen evolution reaction...     

非贵金属Ni2P助催化剂修饰KCa2Nb3O10超薄纳米片的光解水产氢性能研究

开发高效非贵金属助催化剂是光解水产氢领域研究的重点.首次将Ni2P纳米颗粒作为高效助催化剂经一步热处理法修饰在KCa2Nb3O10超薄纳米片表面,成功构建了Ni2P/KCa2Nb3O10复合光催化剂,所制备的复合光催化剂展现出具有丰富异质界面的二维纳米结构,活性最佳的Ni2P/KCa2Nb3O10产物光催化产氢效率高达72.25μmol g-1 h-1,是纯相KCa2Nb3O10产氢效率的18.8倍.提供了一种负载其他非贵金属助催化剂制备高效KCa2Nb3O10基复合光催化剂的新策略.     

Recent Advances in Boron Nitride Nanotubes and Nanosheets

Herein the recent experiments performed by the authors on fabricated multi-walled BN nanotubes and monoatomic BN graphene-like nanosheets are reviewed. The results are presented in several sections, namely: (i) method for high-yield synthesis of thin, defect-free BN nanotubes of only a few-layers, with external diameters below 10 nm; (ii) verification of BN nanotube piezoelectrical behavior and its electrically-induced thermal decomposition under combined resistive heating and electrical charging in a transmission electron microscope; (iii) the first direct measurements of the true tensile strength and Young’s modulus of BN nanotubes, using newly developed nanotensile tests inside an electron microscope; the measured values were found to be ∼30 GPa and ∼900 GPa, respectively; and (iv) diverse kinetic processes taking place within the prepared monoatomic BN sheets (so-called “white graphenes”) affiliated with intensive knock-on B and N atom displacements under high energy electron beam irradiation in an aberration-corrected medium-voltage high-resolution transmission electron microscope.     

Amorphous CoMoSx/N-Doped Carbon Hybrid with 3D Networks as Electrocatalysts for Hydrogen Evolution

Catalysis Letters - Catalytic materials without using precious metallic elements for electrocatalytic water splitting are a crucial demand to the renewable energy production. Cobalt molybdenum...     

Evolution of Carbon during Burnout and Sintering of Tape-Cast Aluminum Nitride

The surface nature and the composition of AlN powder, as-received and exposed to binder burnout, were studied using XPS and TEM. The surface of as-received AlN powder was covered by a thin layer of aluminum oxynitride and oxide mixture. A small portion of residual carbon from binder burnout was bound to oxygen atoms on the AlN powder surface, and the majority of the carbon was amorphous graphitoid carbon which covered the AlN powder surface uniformly. AlN samples were made using tape casting and pressureless sintering. Surface-carbon-to-oxygen ratio of AlN powder after binder burnout was evaluated using XPS. The surface C/O atomic ratios were observed to correlate with the sintering behavior, the composition of the second phase, the second phases distribution, and grain-boundary composition, as well as thermal conductivity of AlN samples.     

活性炭负载镍析氢电催化剂的制备和表征

采用化学还原法制备了以椰壳活性炭(AC)为载体的Ni/AC电催化剂。运用SEM和XRD对Ni/AC电催化剂的形貌和结构进行了分析。研究了镍负载量、制备温度和还原剂N2H4与Ni2+的摩尔比对Ni/AC电催化剂析氢催化活性的影响。结果表明,负载在活性炭上的镍为面心立方晶系,其镍的负载量、制备温度和N2H4(还原剂)/Ni2+摩尔比对Ni/AC电催化剂的析氢催化活性有显著的影响。     

Boron Nitride Nanosheets Strengthened PVA/Borax Hydrogels with Highly Efficient Self-Healing and Rapid pH-Driven Shape Memory Effect

Self-healing hydrogels often possess poor mechanical properties which largely limits their applications in many fields. In this work, boron nitride nanosheets are introduced into a network of the poly(vinyl alcohol)/borax (PVA/borax) hydrogels to enhance the mechanical properties of the hydrogel without compromising the self-healing abilities. The obtained hydrogels exhibit excellent mechanical properties with a tensile strength of 0.410 ± 0.007 MPa, an elongation at break of 1712%, a Young's Modulus of 0.860 ± 0.023 MPa, and a toughness of 3.860 ± 0.075 MJ m⁻³. In addition, the self-healing efficiency of the hydrogels is higher than 90% within 10 min at room temperature. Benefiting from the excellent self-healing properties, the shapeability of the hydrogel fragments is observed using different molds. In addition, the hydrogels display rapid pH-driven shape memory effects and can recover to their original shape within 260 s. Overall, this work provides a new approach to hydrogels with integrated excellent mechanical properties, self-healing abilities, and rapid pH-driven shape memory effects.     

二氧化钛光催化降解塑料研究进展

从提高二氧化钛( TiO2)光催化效率及太阳光利用率的各种改性及TiO2固相光催化降解的机理等方面综述了近年来国内外TiO2光催化降解塑料的研究进展,探讨了光催化降解塑料的应用前景及存在的问题.     

Conversion of Alumina to Aluminum Nitride Using Polymeric Carbon Nitride as a Nitridation Reagent

Polymeric carbon nitride, which was synthesized by polymerization of dicyandiamide at 500°C, was used as a nitridation reagent in the conversion of δ‐alumina (δ‐Al₂O₃) to aluminum nitride (AlN). The products obtained at various reaction temperatures were characterized by powder X‐ray diffraction, ²⁷Al magic‐angle spinning nuclear magnetic resonance (MAS NMR) spectroscopy, Raman spectroscopy, and X‐ray photoelectron spectroscopy (XPS). δ‐Al₂O₃ began to convert to AlN at 900°C, which is the lowest temperature reported for the formation of AlN from Al₂O₃, and completely converted to AlN at 1400°C. The occurrence of reaction intermediates during nitridation was confirmed by ²⁷Al MAS NMR and XPS. The change in Raman spectra with reaction temperatures indicated that lattice defects in AlN were reduced by calcining at higher reaction temperatures.     

Co-Doped MoSe2 Nanoflowers as Efficient Catalysts for Electrochemical Hydrogen Evolution Reaction (HER) in Acidic and Alkaline Media

Transition metal dichalcogenides (TMDCs) based materials are considered as highly active alternatives to the precious Pt-based catalysts for the hydrogen evolution reaction (HER). In particular, MoSe₂ emerges as a promising catalyst due to its abundance and electrochemical stability, but further modifications are still required to enhance its performance, specifically in alkaline conditions. Here, we developed a method to obtain MoSe₂ with two cobalt doping patterns: homogeneously doped and edge doped nanoflowers, with abundant edge sites and extended surface area. The results show that low concentration of doping enhances the catalytic activity toward HER. Incorporation of cobalt as a substituent dopant within the layered structure of MoSe₂ appears to have two major contributions: it changes the chemical environment providing more active sites with favored hydrogen adsorption properties, and improves the charge transfer resistance and thus facilitates the HER kinetics. Moreover, the homogeneous and edge-doped nanoflowers show different pH-dependence of HER activity. Edge-doped samples exhibit significantly improved performance in acidic medium, while the overpotential increases in alkaline environment upon doping. A mechanistic explanation of the observed effect is proposed. This work opens up an additional path for improving the catalytic activity of TMDCs in acidic or alkaline medium using a simple and facile method with only small quantities of dopants.