Retrospective on Exploring MXene-Based Nanomaterials: Photocatalytic Applications.

Nanostructural two-dimensional compounds are grabbing the attention of researchers all around the world. This research is progressing quickly due to its wide range of applications in numerous industries and enormous promise for future technological breakthroughs. Growing environmental consciousness has made it vital to treat wastewater and avoid releasing hazardous substances into the environment.

Bias-Modified Schottky Barrier Height-Dependent Graphene/ReSe van der Waals Heterostructures for Excellent Photodetector and NO Gas Sensing Applications.

Herein, we reported a unique photo device consisting of monolayer graphene and a few-layer rhenium diselenide (ReSe) heterojunction. The prepared Gr/ReSe-HS demonstrated an excellent mobility of 380 cm/Vs, current on/off ratio ~ 10, photoresponsivity (R ~ 74 AW @ 82 mW cm), detectivity (D ~ 1.25 × 10 Jones), external quantum efficiency (EQE ~ 173%) and rapid photoresponse (rise/fall time ~ 75/3 µs) significantly higher to an individual ReSe device (mobility = 36 cm Vs, Ion/Ioff ratio = 1.

N doped FeP nanospheres decorated carbon matrix as an efficient electrocatalyst for durable lithium-sulfur batteries.

Rational design and synthesis of multifunctional electrocatalysts with high electrochemical activity and low cost are significantly important for new-generation lithium-sulfur (Li-S) batteries. Herein, N-doped FeP nanospheres decorated N doped carbon matrix is successfully synthesized by facile one-pot pyrolysis and in-situ phosphorization technique to mitigate the conversion kinetics and suppress the shuttle effect. The large specific surface area with mesopores can incorporate up to 81.

Separation of Fe from wastewater and its use for NO reduction; a sustainable approach for environmental remediation.

The nitrogen and sulphur oxide (NO and SO) emissions are causing a serious threat to the existence of life on earth, requiring their effective removal for a sustainable future. Among various approaches, catalytic or electrochemical reduction of air pollutants (NO) has gained much attention due to its high efficiency and the possibility of converting these gases into valuable products. However, the required catalysts are generally synthesized from lab-grade chemicals, which may not be a sustainable approach.

Removal of persistent acetophenone from industrial waste-water via bismuth ferrite nanostructures.

Increasing water pollution is a severe problem in densely industrialized countries. Nanomaterials provide strong potentials for the efficient elimination of organic pollutants due to their beneficial properties. Advancement in water purification is required to more efficiently remove the emerging organic contaminants, especially in pharmaceuticals wastes such as acetophenone, which shows high solubility in industrial wastewaters.

Effect of Co-Doping on Thermoelectric Properties of -Type BiTe Nanostructures Fabricated Using a Low-Temperature Sol-Gel Method.

In this work, a novel low-temperature double solvent sol-gel method was used to fabricate (Sm, Ce, Gd) and (Sn, Se, I) co-doped at Bi and Te-sites, respectively, for BiTe nanostructures. The phase-purity and high crystallinity of as-synthesized nanostructures were confirmed using X-ray diffraction and high-resolution transmission electron microscopy. The nanopowders were hot-pressed by spark plasma sintering into bulk pellets for thermoelectric properties.

Synthesis of 3D IrRuMn Sphere as a Superior Oxygen Evolution Electrocatalyst in Acidic Environment.

The design of a three-dimensional structure for an Ir-based catalyst offers a great opportunity to improve the electrocatalytic performance and maximize the use of the precious metal. Herein, a novel wet chemical strategy is reported for the synthesis of an IrRuMn catalyst with a sphere structure and porous features. In the synthetic process, the combined use of citric acid and formamide is requisite for the formation of the sphere structure.

Synthesis of self-assembled PtPdAg nanostructures with a high catalytic activity for oxygen reduction reactions.

Designing a self-assembling structure for a Pt-based catalyst offers a great opportunity to enhance the electrocatalytic performance and maximize the use of precious metals. Herein, we report an etching method based on thermal treatment for the removal of less active metals from Pt-based alloys for the enhancement of the oxygen reduction reaction. PtPdAg nanostructures' self-assembly can be easily controlled to the dimer stage or nanowires by stirring the nanoparticles in formamide with or without potassium iodide under heat for specific times.

Multimetallic nanosheets: synthesis and applications in fuel cells.

Two-dimensional nanomaterials, particularly multimetallic nanosheets with single or few atoms thickness, are attracting extensive research attention because they display remarkable advantages over their bulk counterparts, including high electron mobility, unsaturated surface coordination, a high aspect ratio, and distinctive physical, chemical, and electronic properties. In particular, their ultrathin thickness endows them with ultrahigh specific surface areas and a relatively high surface energy, making them highly favorable for surface active applications; for example, they have great potential for a broad range of fuel cell applications. First, the state-of-the-art research on the synthesis of nanosheets with a controlled size, thickness, shape, and composition is described and special emphasis is placed on the rational design of multimetallic nanosheets.

From a ureidopyrimidinone containing organic precursor to excavated iron-nitrogen codoped hierarchical mesoporous carbon (Ex-FeN-MC) as an efficient bifunctional electrocatalyst.

A hierarchical excavated iron-nitrogen codoped mesoporous carbon (Ex-FeN-MC) electrocatalyst has been successfully synthesized by pyrolysis of the unique ureidopyrimidinone containing organic precursor MAMIS by using silica as the mesoporous template and iron nitrate as the source of iron. The selected organic precursor has multifunctionalities with diverse distribution of nitrogen and oxygen species which constitute interesting features to prepare the Ex-FeN-MC electrocatalyst. The as-prepared Ex-FeN-MC material shows unexpectedly higher catalytic activities towards ORR/OER performances with an overpotential of 250 mV for OER in alkaline solution at a current density of 10 mA cm, while the ORR activity is almost similar to that of commercial Pt/C.

Iron Hydroxide-Modified Nickel Hydroxylphosphate Single-Wall Nanotubes as Efficient Electrocatalysts for Oxygen Evolution Reactions.

Development of efficient electrocatalysts for oxygen evolution reaction (OER) is of great significance for future renewable energy applications. Herein, efficient OER electrocatalysts based on iron hydroxide-modified nickel hydroxylphosphate (NiPO/Fe(OH) ) single-wall nanotubes (SWNTs) have been prepared by a facile stepwise surfactant-free solvothermal strategy, which possess diameters of about 6 nm and lengths of about several micrometers. Benefiting from the synergistic effect between iron hydroxides and NiPO SWNTs, the as-prepared NiPO/Fe(OH) SWNTs exhibit higher OER activity than primary NiPO SWNTs.

Silver nanocrystal-decorated polyoxometalate single-walled nanotubes as nanoreactors for desulfurization catalysis at room temperature.

Ultrathin nanocrystals generally provide a remarkable catalytic performance due to their high specific surface area and exposure of certain active sites. However, deactivation caused by growth and gathering limits the catalytic application of ultrathin nanocrystals. Here we report Ag nanocrystal-decorated polyoxometalate (Ag-POM) single-walled nanotubes assembled via a concise, surfactant-free soaking method as a new kind of well-defined core-sheath nanoreactor.

Shape controlled synthesis of porous tetrametallic PtAgBiCo nanoplates as highly active and methanol-tolerant electrocatalyst for oxygen reduction reaction.

Mechanistic control is a powerful means for manufacturing specific shapes of metal nanostructures and optimizing their performance in a variety of applications. Thus, we successfully synthesized multimetallic nanoplates (PtAgBiCo and PtAgBi) by combining the concepts of crystal symmetry, oxidative etching and seed ratio, and tuned their activity, stability and methanol tolerance, as well as Pt utilization, for the oxygen reduction reaction in direct methanol fuel cells. Systematic studies reveal that the formation of PtAgBiCo triangular nanoplates with a high morphological yield (>90%) can be achieved by crystallinity alteration, while electrochemical measurements indicate that the PtAgBiCo nanoplates have superior electrocatalytic activity towards the oxygen reduction reaction.

Porous Tetrametallic PtCuBiMn Nanosheets with a High Catalytic Activity and Methanol Tolerance Limit for Oxygen Reduction Reactions.

Porous PtCuBiMn nanosheets are developed with a thickness of ≈3-4 nm. The specific and mass activities of these nanosheets are ten and seven times greater than that of commercial Pt/C catalyst, respectively. PtCuBiMn nanosheets demonstrate superior catalytic performance for the oxygen reduction reaction, as well as resistance to methanol cross-over effects, suggesting that it is a promising catalyst for direct methanol fuel cells.