This research demonstrates a chemical potential modulated strategy for the realization of ultrathin transition metal boride (TMB) single crystals with ultrahigh phase purity (approximately 100%). The uniform distribution of precursor ensures a very narrow compositing window that permits the monophasic nucleation and growth of ultrathin TMBs.

Graphene is an atomically thin material for which all atoms are exposed to the interfaces that need to be studied using a nondestructive and sensitive technique. In this review, we summarize and discuss that how to characterize these interfaces by synchrotron radiation techniques to understand the structure and property evolution of graphene.

For the first time, we achieve the synthesis of a wide variety of high-quality 2D REO single crystals with tailorable facets via designing a hard-soft-acid-base couple for controlling the 2D nucleation of the predetermined facets and adjusting the growth mode and direction of crystals.

Based on the good solubility, layering property, rheological property and excellent conductivity, the liquid metal reaction system in the “Eight Trigrams Furnace” is constantly providing surprises for designing advanced materials including 2D materials and composite materials for a wide range of applications in electronics, photonics, and energy field.

In article number 2100334, Lei Fu, Mengqi Zeng and co-workers open the “black box” of the growth, movement and self-assembly of graphene on liquid metal via in-situ technique. Graphene can translate, rotate and spontaneously tend to be evenly distributed on liquid metal. This work offers an innovative way to explore the dynamic growth process and mechanism of 2D materials.

Recently, two-dimensional (2D) metal-organic frameworks (MOFs) have attracted much attention as a class of promising electrocatalysts. Their diverse components and tunable structures provide a new platform to design and explore ideal electrocatalysts. The ultrathin characteristics including high specific surface area, abundant exposed metal sites and fast electronic transfer further promote the electrocatalytic performance of 2D MOFs. This review focuses on the strategies to fabricate 2D MOFs with high electrocatalytic performances for OER.

We firstly get an access to the insight into the rapid growth of large graphene single crystal on liquid metal. We have achieved the growth of millimeter-size graphene single crystal on liquid Cu. The rich free electrons in liquid Cu accelerate the nucleation, and the isotropic smooth surface greatly suppresses the nucleation. What’s more, the fast mass-transfer of carbon atoms due to the excellent fluidity of liquid Cu promotes the fast growth with the rate up to 79 µm s–1.

The exciting progress in controlled growth, etching, self-assembly, and delivery of graphene on a liquid surface can be achieved, promoting its future industrial applications. The poem in the cover translates as “The pools in south China are suitable for gathering lotus. How dense and flourishing are the lotus leaves!” The lotus leaves floating in the pools represent graphene single crystals grown on liquid substrates.

We demonstrate the disassembly of 2D vertical heterostructures with the activation of specific disassembly promoters (DPs) and the weakening of the interlayer van der Waals interaction, which initially establishes the inverse process to 2D material assembly. The unique disassembly process has remarkable prospects toward the modification and functionalization of 2D materials, which opens up a novel pathway to functionally integrated devices.

The two-dimensional (2D) GaN single crystals can be grown on liquid metals with urea as precursors via a surface-confined nitridation reaction strategy, which can pave the way to further explore the electronic and optical properties of GaN in the 2D limit.

Lei Fu and co-workers enforce a smart self-adapting wettability (SAQ) of ReS₂ under sustained light irradiation, which breaks the stereotype that a single stimulus leads to a monotonic change in properties or structure. This unique SAW provides a brand-new insight to broaden the applications of responsive materials, which will undoubtedly pave a novel way in further device optimization.

A change of the metal catalyst in the physical state from the traditional solid to liquid brings about a qualitative change and improvement in the controllable fabrication of two-dimensional (2D) materials. The unique self-limited growth, self-assembly, and sliding transfer behaviors of 2D materials on liquid metals are fully exhibited.

In this article, Mengqi Zeng, Lei Fu, and co-workers review a class of high-efficiency atomic scale materials (ASMs) catalysts. The distinct structural characteristics endow them with great catalytic advantages, especially the maximum atomic utilization. ASMs catalysts have demonstrated their superior catalytic performance in various core catalytic reaction systems. It is envisioned that these will open up a new territory in catalysis.

Lei Fu and co-workers present a new catalyst: nanometric Ni₅P₄ clusters nested on NiCo₂O₄ nanoflakes. Due to the small energy barrier of water dissociation on NiCo₂O₄ and the low hydrogen adsorption free energy of Ni₅P₄, the as-demonstrated nanocomposite exhibits superior catalytic activity for alkaline water electrolysis, which outperforms many other non-noble electrocatalysts.

The back cover picture shows four effective routes are applied to the anode material to help it keep fit, which is out of shape due to the intake of sodium ions. As a result, the sodium ion batteries (SIBs) with this anode exhibit high electrochemical performances so that they tend to meet the demand for large-scale energy storage devices. In this review, four strategies based on structural designs are summarized in order to accommodate volume changes of anode materials in SIBs, including nanoarchitecture configuration, buffer matrix protection, cavity volume reservation, and interlayer spacing regulation.

A Cu-assisted self-limited growth method is proposed to achieve the ultra-fast growth of strictly monolayer and high-quality WSe₂ crystals. Cu can prevent the layer accumulation since it occupies the surface of the WSe₂ crystals, thus the W atoms can only adsorb on the edge site to achieve the size extension.

A hexagonal-boron nitride (h-BN) self-aligned single-crystal array (SASCA) is reported by Lei Fu and co-workers. The h-BN SASCA shows orderly alignment and uniformly distribution. Moreover, it exhibits highly accordant spatial orientation and homogenous domain size, which can realize highly integrated and individually switching field-effect transistors (FETs) when serving as gate dielectrics. Additionally, circular h-BN single-crystals, which are considered as the building blocks of h-BN SASCA, are also observed.