Rui Tong

Bio: Rui Tong is an academic researcher from University of Macau. The author has contributed to research in topics: Electrocatalyst & Water splitting. The author has an hindex of 12, co-authored 24 publications receiving 606 citations. Previous affiliations of Rui Tong include Hubei University.

Temperature-Mediated Selective Growth of MoS2/WS2 and WS2/MoS2 Vertical Stacks on Au Foils for Direct Photocatalytic Applications

Abstract: A growth-temperature-mediated two-step chemical vapor deposition strategy is designed to synthesize MoS2 /WS2 and WS2 /MoS2 stacks on Au foils. Predominantly A-A stacked MoS2 /WS2 and A-B stacked WS2 /MoS2 are selectively achieved and confirmed. Relative enhancements or reductions in photocatalytic activities of MoS2 /WS2 or WS2 /MoS2 are observed under illumination, because the type-II band alignment enables directional electron flow from electrode to active site.

Surface Roughening of Nickel Cobalt Phosphide Nanowire Arrays/Ni Foam for Enhanced Hydrogen Evolution Activity.

Abstract: Development of earth-abundant, efficient, and stable electrocatalysts for hydrogen evolution reactions (HER) in alkaline or even neutral pH electrolyte is very important for hydrogen production from water splitting. Construction of bimetal phosphides via tuning the bonding strength to hydrogen and increasing effective active sites through nanostructuring and surface engineering should lead to high HER activity. Here, ternary NiCoP nanowires (NWs) decorated by homogeneous nanoparticles have been obtained on Ni foam for a highly efficient HER property via long-term cyclic voltammetric (CV) sweeping. The electron density transfer between the positively charged Ni and Co and negatively charged P atoms, one-dimensional electron transfer channel of the NWs, and abundant active sites supplied by the nanoparticles and NWs endow the catalyst with low overpotentials of 43 and 118 mV to achieve the respective current densities of 10 and 100 mA cm–2 together with long durability for at least 33 h in 1 M KOH. A cycled...

Efficient nitrogen fixation to ammonia on MXenes.

Abstract: Active catalysts for nitrogen fixation (N2-fixation) have been widely pursued through constant efforts for industrial applications. Here, we report a family of catalysts, MXenes (M2X: M = Mo, Ta, Ti, and W; X = C and N), for application in N2-fixation based on density functional theory calculations. We find that the catalytic performance of MXenes strongly depends on the reaction energy in each reaction step. More exothermic steps lead to higher catalytic performance in the course of N2-fixation. We show that the reaction energy in N2-fixation is strongly affected by the charge transfer: (1) if N atoms gain more electrons in a step, the reaction is exothermic with a larger reaction energy; (2) if N atoms lose electrons in a step, the reaction is endothermic in general. We further show that Mo2C and W2C are highly active for N2-fixation due to their exothermic reactions and strong charge transfer, which may be applicable in the chemical-engineering industry.

Two-dimensional materials as novel co-catalysts for efficient solar-driven hydrogen production

Abstract: Hydrogen has attracted extensive attention due to its versatile applications in various fields. As the starting step, hydrogen production is a critical technique for the practical application of hydrogen-related technologies. Solar-driven water splitting is considered one of the cleanest methods for hydrogen production because solar power is abundant and clean, and the products are only hydrogen and oxygen. Consequently, strategies to increase the efficiency of solar-to-hydrogen conversion have been widely explored. Based on the basic requirements, loading of co-catalysts for photocatalysis is emerging as an effective method to improve the efficiency of solar-driven water splitting. In this review, we shall systematically discuss the recent developments in two-dimensional (2D) materials, including graphene, 2D transition-metal dichalcogenides (TMDs), and MXenes, for their application as co-catalysts in photocatalytic/photoelectrochemical H2 evolution. It is noted that highly efficient electrocatalysts for the hydrogen evolution reaction (HER) by electrocatalysis can be used as superior co-catalysts for photocatalysis. Therefore, various methods to improve the HER activity of co-catalysts, such as phase-control, doping, defect engineering, hybridization, and functionalization, have been adopted to increase the photocatalytic performances of decorated photocatalysts, which are also systematically discussed. Through a comprehensive literature review, we summarize and propose this concept, that is, “electrocatalysts can be used as co-catalysts in photocatalysis for the improvement of solar-driven H2 evolution”. We believe that this concept will shed light on the development of technologies in photocatalytic hydrogen production for practical applications. At the same time, we trust that efficient, inexpensive and stable co-catalysts will be designed and fabricated not only to promote the efficiency of solar-driven hydrogen production on a large scale, but also to be beneficial for other catalytic processes.

Cocatalysts for Selective Photoreduction of CO2 into Solar Fuels.

Abstract: Photoreduction of CO2 into sustainable and green solar fuels is generally believed to be an appealing solution to simultaneously overcome both environmental problems and energy crisis. The low selectivity of challenging multi-electron CO2 photoreduction reactions makes it one of the holy grails in heterogeneous photocatalysis. This Review highlights the important roles of cocatalysts in selective photocatalytic CO2 reduction into solar fuels using semiconductor catalysts. A special emphasis in this review is placed on the key role, design considerations and modification strategies of cocatalysts for CO2 photoreduction. Various cocatalysts, such as the biomimetic, metal-based, metal-free, and multifunctional ones, and their selectivity for CO2 photoreduction are summarized and discussed, along with the recent advances in this area. This Review provides useful information for the design of highly selective cocatalysts for photo(electro)reduction and electroreduction of CO2 and complements the existing reviews on various semiconductor photocatalysts.

Applications of 2D MXenes in energy conversion and storage systems

Abstract: Transition metal carbides and nitrides (MXenes), a family of two-dimensional (2D) inorganic compounds, are materials composed of a few atomic layers of transition metal carbides, nitrides, or carbonitrides. Ti3C2, the first 2D layered MXene, was isolated in 2011. This material, which is a layered bulk material analogous to graphite, was derived from its 3D phase, Ti3AlC2 MAX. Since then, material scientists have either determined or predicted the stable phases of >200 different MXenes based on combinations of various transition metals such as Ti, Mo, V, Cr, and their alloys with C and N. Extensive experimental and theoretical studies have shown their exciting potential for energy conversion and electrochemical storage. To this end, we comprehensively summarize the current advances in MXene research. We begin by reviewing the structure types and morphologies and their fabrication routes. The review then discusses the mechanical, electrical, optical, and electrochemical properties of MXenes. The focus then turns to their exciting potential in energy storage and conversion. Energy storage applications include electrodes in rechargeable lithium- and sodium-ion batteries, lithium-sulfur batteries, and supercapacitors. In terms of energy conversion, photocatalytic fuel production, such as hydrogen evolution from water splitting, and carbon dioxide reduction are presented. The potential of MXenes for the photocatalytic degradation of organic pollutants in water, such as dye waste, is also addressed, along with their promise as catalysts for ammonium synthesis from nitrogen. Finally, their application potential is summarized.

Chemical Vapor Deposition Growth and Applications of Two-Dimensional Materials and Their Heterostructures

Abstract: Two-dimensional (2D) materials have attracted increasing research interest because of the abundant choice of materials with diverse and tunable electronic, optical, and chemical properties. Moreover, 2D material based heterostructures combining several individual 2D materials provide unique platforms to create an almost infinite number of materials and show exotic physical phenomena as well as new properties and applications. To achieve these high expectations, methods for the scalable preparation of 2D materials and 2D heterostructures of high quality and low cost must be developed. Chemical vapor deposition (CVD) is a powerful method which may meet the above requirements, and has been extensively used to grow 2D materials and their heterostructures in recent years, despite several challenges remaining. In this review of the challenges in the CVD growth of 2D materials, we highlight recent advances in the controlled growth of single crystal 2D materials, with an emphasis on semiconducting transition meta...