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With the increasing severity of the water crisis, electrochemical capacitive deionization has emerged as a promising technology for water purification. Graphene is a powerful candidate among carbon materials for the electrochemical electrode, and monolithic graphene is a high-end material for capacitive deionization considering its potentially large surface area and fast adsorption kinetics. However, monolithic graphene electrode materials still suffer from either weak deionization performances or high manufacturing costs. Herein, a novel electrode material, a porous monolith composed of nitrogen-doped graphene building-blocks, has been developed via low-cost zinc-assisted pyrolysis. The monolith is hydrophilic, possesses a high specific surface area, and has abundant hierarchical mesopores. Remarkable electrochemical capacitive deionization performances are provided by such a graphene monolith, with a salt adsorption capacity of 39.6 mg g−1 and a salt adsorption rate near 3.5 mg g−1 min−1. This development thus underlines the promise of novel monolithic electrode materials for high-efficiency desalination of seawater into freshwater. [ABSTRACT FROM AUTHOR]

We developed an efficient MoS2 nanosheet electrode coupled with CeO2via a hydrothermal process to facilitate water adsorption and dissociation, which displayed good HER activity and stability at a large current density of 500 mA cm−2. In situ Raman spectroscopy confirmed the formation of hydroxide ions based on the strengthening of the Ce–O bond during the HER. [ABSTRACT FROM AUTHOR]

Graphene and boron nitride (BN) foams, as two types of three‐dimensional (3D) nanomaterials consisting of two‐dimensional (2D) nanosheets, can inherit a series of excellent properties of the 2D individuals. The internal 3D network can prevent aggregation or restacking between isolated graphene or BN nanosheets, and provide a highway for phonon/electron transports. Moreover, the interconnected porous structure creates a continual channel for the mass exchange of exotic species. The light‐element graphene and BN foams can thus possess the characteristics of low density, high porosity, high surface area, and excellent mechanical, thermal, and electrical properties. Benefiting from these advantages, they show a wide range of applications. The usual synthesis methods and the recent functional applications of graphene and BN foams are reviewed herein, including their applications as supporting materials, elastic materials, acoustic shielding materials, thermal interface materials, electromagnetic shielding materials, adsorption materials, electrocatalysis and thermal catalyses materials, electrochemical energy storage, and thermal energy storage materials. Current challenges and outlooks are additionally discussed. [ABSTRACT FROM AUTHOR]

Advanced sorbents for water purification need to be developed for environmental protection. Porous boron nitride (BN) is a high-end material for the removal of pollutants for its remarkable sorption characteristics and chemical inertia. However, it still suffers from thick pore walls, low yield and powdery state, limiting the performance. Herein, a borax-based template-free pyrolysis route is developed to massively produce the cellular monolith of a few-atomic-layered boron nitride. It possesses ultra-thin pore walls and uniform mesopores, resulting from the phase-separation-dominated pore-forming mechanism. Such a porous monolith is applied for water purification, showing high adsorption capacity on Congo red (1096 mg g−1), which is attributed to mesopores and surface polarity. It further exhibits unprecedented recyclability, relying on its anti-oxidation stability. A prototype of the water filter pitcher using this BN is finally demonstrated with commendable performances. The aerogel-like BN bulk material enables a high-capacity recyclable sorbent, representing a leap forward toward practical water purification. [ABSTRACT FROM AUTHOR]

For delivering the nanoscaled extraordinary characteristics in macroscopical bulk, it is essential to integrate two‐dimensional nanosheets into three‐dimensional (3D) porous monoliths, alternatively called as 3D architectures, 3D networks, or aerogels. The intersupported structure of porous monolithic 3D graphene (3DG) can prevent aggregation or restacking of graphene individuals, and the interconnected sp2 network of 3DG not only can provide the highway for the transport of electron/phonon but also can present continual cavities/channels for mass transfer. This review summarizes the synthesis methodology of 3DG porous monoliths and highlights the application for electric double‐layer capacitors. Present challenges and future prospects about the manufacture and application of 3DG are also discussed. [ABSTRACT FROM AUTHOR]

Physiological (metabolite analysis) and molecular (gene expression) approaches were used to understand the mechanism underlying russet formation in response to the application of GA3 and CPPU (Forchlorfenuron) in a Japanese table grape cultivar 'Shine Muscat'. Several different concentrations of GA3 and GA3 + CPPU [25 mg L−1 GA3 (A), 25 mg L−1 GA3 + 5 mg L−1 CPPU (B), 25 mg L−1 GA3 + 10 mg L−1 CPPU (C), and 25 mg L−1 GA3 + 15 mg L−1 CPPU (D)] were applied to grape berry clusters at two weeks after flowering (WAF). No russet was observed on the berries treated with the 'C' combination. Lower levels of phenylalanine ammonia-lyase (PAL) activity was observed in the treated samples, relative to the untreated material. Reduced peroxide (POD) activity was also observed in response to different treatments, while the expression of Peroxidase 17 and Phenylalanine ammonia-lyase G1 genes mirrored lignin content. Increased activity of 4-coenzyme A ligase (4CL) may contribute to decreasing the level of russet and help to improve grape berry quality. [ABSTRACT FROM AUTHOR]

Hollow metal oxides and carbon hybrids with hierarchical and robust nanoarchitecture hold great potential as high-performance electrode materials. Herein, a relatively unexplored hollow and hierarchical metal–organic framework (MOF) assembled by parallel stacked triangular sub-MOFs were successfully synthesized via a facile co-precipitation method. The hollow MOFs were then converted to binary metal oxides@carbon composites, exemplified herein as Zn–Mn mixed oxides@carbon (ZnxMnO@C) hybrids. The obtained ZnxMnO@C inherits the unique hollow hexagonal nanodisks (HHNDs) structure of the MOF precursor, and each triangular plate-like subunit consists of a continuous carbon matrix embedded uniformly within the ultrafine ZnxMnO nanoparticles. When evaluated as an anode material for lithium ion batteries, the ZnxMnO@C HHNDs exhibited high specific capacity (1050 mA h g−1 at 0.1 A g−1 after 200 cycles) and remarkable cycling performance up to 1000 cycles. It is believed that besides the protection of the carbon matrix, the unique hierarchically hollow structure with parallel stacked subunits endows the ZnxMnO@C hybrid with additional capability to withstand lithiation/delithiation strain. Moreover, kinetics-analysis based on cyclic voltammograms (CVs) reveals that the high lithium storage capacity is primarily attributed to fast kinetics originating from pseudocapacitive contribution. This also accounts for the good rate capabilities of ZnxMnO@C HHNDs (713 and 330 mA h g−1 at 1 and 10 A g−1, respectively). Furthermore, full cells with Zn0.5MnO@C anodes and LiMn2O4 cathodes are assembled and show good cycling stability over 120 cycles. This study demonstrates a new hollow structure of MOFs and its usefulness in developing robust and hierarchical metal oxide/carbon composites for electrochemical storage applications. [ABSTRACT FROM AUTHOR]

Water purification via interfacial solar steam generation exhibits promising potential. However, salt crystallization on evaporators reduces solar absorption and obstructs water supply. To address it, a waffle-shaped solar evaporator (WSE) has been designed. WSE is fabricated via a zinc-assisted pyrolysis route, combining low-cost biomass carbon sources, recyclable zinc, and die-stamping process. This route enables cost-effective production without the need of sophisticated processing. As compared to conventional plane-shaped evaporators, WSE is featured by extra sidewalls for triggering the convection with the synergistic solute and thermal Marangoni effects. Consequently, WSE achieves spontaneous salt rejection and durable evaporation stability. It has demonstrated continuous operation for more than 60 days in brine without fouling.

We developed an efficient MoS 2 nanosheet electrode coupled with CeO 2 via a hydrothermal process to facilitate water adsorption and dissociation, which displayed good HER activity and stability at a large current density of 500 mA cm -2 . In situ Raman spectroscopy confirmed the formation of hydroxide ions based on the strengthening of the Ce-O bond during the HER.