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Two-dimensional (2D) layered materials are assembled through the intralayer covalent bonds and interlayer van der Waals (vdWs) interactions. The relatively weak interlayer vdWs interactions result in the weak interlayer mechanical coupling between layers, which strongly impacts the overall mechanical properties of multilayer 2D materials or heterostructures. Experimentally probing the interlayer mechanical coupling is of vital importance on the accumulation of fundamental parameters for their applications in flexible and stretchable devices, yet there are hardly comprehensive reviews in this research field. In this review, we firstly introduce the probing methods of interlayer mechanical coupling, including high-frequency and ultralow-frequency Raman characterizations, nanoindentation of multilayer 2D materials or heterostructures, surface indentation, pressurized blister test, characterization of spontaneously formed nanoblisters, and nano-friction tests. Based on the analysis and comparison of the existing methods and results, we also discuss the advantages and limitations of each method. Finally, the challenges and opportunities in this promising field are discussed. This review summarizes the recent progress in the probing of interlayer mechanical coupling of 2D layered materials and will provide important reference for the rational design of flexible and stretchable devices. [Display omitted] • The interlayer interactions strongly impact the mechanical properties of multilayer 2D materials or heterostructures. • Probing the interlayer mechanical coupling of 2D materials is very important for the accumulation of fundamental parameters. • The current experimental methods of probing the interlayer mechanical coupling of 2D layered materials are summarized. [ABSTRACT FROM AUTHOR]

Cu 2 O is an ideal template material for the preparation of transition metal hydroxide/oxyhydroxides with oxygen evolution reaction (OER) enhanced catalytic performance. Here, inspired by Pearson's principle, Cu 2 O wires were prepared and used as a sacrificial template to prepare Ni(OH) 2 ·0.75H 2 O hollow tubes (Ni(OH) 2 HTs) with highly improved surface roughness. Benefiting from unique structural advantages, the Ni(OH) 2 HTs showed excellent catalytic activity, rapid kinetics and a long-term stability as the OER catalyst, where an overpotential of only 207 ​mV was required to drive a current density of 10 ​mA ​cm−2, an ideal kinetics with a Tafel slope as 79.8 ​mV dec−1 was calculated, and no obvious attenuation in chronoamperometry was discovered after operation for 24 ​h. This paper provides a novel template-assisted strategy to prepare high-performance transition metal-based OER catalysts possessing hollow and tubular structures. [Display omitted] • For the first time , we used Cu 2 O wires as hard template to prepare hollow tubular Ni(OH) 2. • The Ni(OH) 2 HTs possess novel morphologies with stable hollow one-dimensional structure and rough surface. • As OER catalyst, the Ni(OH) 2 HTs showed excellent electrochemical performances for overpotential, kinetics and stability. [ABSTRACT FROM AUTHOR]