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Abstract A fascinating photonic platform with a small device scale, fast operating speed, as well as low energy consumption is two-dimensional (2D) materials, thanks to their in-plane crystalline structures and out-of-plane quantum confinement. The key to further advancement in this research field is the ability to modify the optical properties of the 2D materials. The modifications typically come from the materials themselves, for example, altering their chemical compositions. This article reviews a comparably less explored but promising means, through engineering the photonic surroundings. Rather than modifying materials themselves, this means manipulates the dielectric and metallic environments, both uniform and nanostructured, that directly interact with the materials. For 2D materials that are only one or a few atoms thick, the interaction with the environment can be remarkably efficient. This review summarizes the three degrees of freedom of this interaction: weak coupling, strong coupling, and multifunctionality. In addition, it reviews a relatively timing concept of engineering that directly applied to the 2D materials by patterning. Benefiting from the burgeoning development of nanophotonics, the engineering of photonic environments provides a versatile and creative methodology of reshaping light–matter interaction in 2D materials. 

Mixed‐dimensional (0D, 1D, and 3D) heterostructures based on 2D layered materials have been proven as a promising candidate for future nanoelectronics and optoelectronics applications. In this work, it is demonstrated that 1D atomic chain based Se nanoplates (NPs) can be epitaxially grown on monolayer ReS₂by a chemical transport reaction, thereby creating an interesting mixed‐dimensional Se/ReS₂heterostructure. A unique epitaxial relationship is observed with the (110) planes of the Se NPs parallel to the corresponding ReS₂(010) planes. Experimental and theoretical studies reveal that the Se NPs could conjugate with underlying monolayer ReS₂via strong chemical hybridization at heterointerface, which is expected to originate from the intrinsic defects of ReS₂. Remarkably, photodetectors based on Se/ReS₂heterostructures exhibit ultrahigh detectivity of up to 8 × 10¹²Jones, and also show a fast response time of less than 10 ms. These results illustrate the great advantage of directly integrated 1D Se based nanostructure on planar semiconducting ReS₂films for optoelectronic applications. It opens up a feasible way to obtain mixed‐dimensional heterostructures with atomic interfacial contact by epitaxial growth.

 

A one‐step synthesis of Li‐rich layered materials with layered/spinel heterostructure has been systematically investigated. The composites are synthesized by a polyol method followed with an annealing process at 500–900 °C for 12 h. A spinel to layer phase transition is considered to take place during the heat treatment, and the samples obtained at different temperatures show diverse phase compositions. An “Li‐rich spinel phase decomposition” phase transition mechanism is proposed to explain the formation of such a heterostructure. The electrochemical properties of the heterostructure are found to be associated with the ratio of spinel to layer phases, the leach out of rock salt phase, and the change of crystallinity and particle size. Product with improved cyclic and rate performance is achieved by annealing at 700 °C for 12 h, with a discharge capacity of 214 mA h g⁻¹remaining at 0.2 C after 60 cycles and discharge capacity of about 200 mA h g⁻¹at 1 C.