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Tellurium (Te), an elemental van der Waals semiconductor, has intriguing anisotropic physical properties owing to its inherent quais‐1D crystal structure. Synthesizing ultrathin Te crystal with uniform orientation is important to its large‐scale device applications, but that remains a great challenge. Herein, the nanoscale grooves‐induced unidirectional epitaxy growth of 1D Te nanowires via physical vapor deposition on the annealed m‐plane sapphire is demonstrated. By enhancing the annealing temperature from 1000 to 1300 °C, nanoscale grooves on m‐plane sapphire arising along the [101¯$\overline 1 $0] direction and gradually distinct, and the corresponding Te nanowires grown on them turns from random to uniform, finally achieving nearly 95% unidirectional Te nanowires. The as‐grown Te nanowires possess high crystallinity with clearly chiral helical chains along the c‐axis direction and reveal thickness‐tunable bandgap with prominent linear‐dichroic. As results, the Te nanowire‐based photodetectors demonstrate a broadband photoresponse from visible (532 nm) to short‐wave infrared (2530 nm), with high responsivity of 327 A W−1 as well as strong and uniform polarization sensitivity (anisotropic ratio = 2.05) to 1550 nm light. The high crystallinity and superior anisotropy of Te nanowires, combined with the orientation‐controlled preparation endows it with great feasibility for constructing chip‐scale multifunctional optoelectronic devices. [ABSTRACT FROM AUTHOR]

Lithium metal is considered as a promising anode for its high energy density and low redox potential. However, dendrite growth and electrolyte‐lithium reaction lead to poor cycling stability of lithium anodes. Herein, a space‐confined strategy is proposed to realize stable Li metal anode by constructing a nonplanar interface with flexible tent‐like nanocavities. The tent‐like interface is achieved through the self‐assembly of graphene oxide on zinc nanosheets, accompanied by the spontaneous formation of ZnOC bond. Remarkably, the ZnOC bond immobilizes the graphene oxide layer to ensure tent‐like structural integrity, and shows excellent lithophilicity to induce homogeneous lithium deposition within nanocavities. Furthermore, the process of Li plating/stripping is confined inside tent‐like nanocavities to effectively decrease electrolyte content contact with fresh Li, which reduces hazardous electrolyte‐lithium reaction and thus eliminates continuous consumption of Li metal. Consequently, the symmetrical cells with the tent‐like interface deliver excellent long cycling performance over 1600 h at 1 mA cm−2, and full batteries show high‐capacity retention of 94.6% after 3000 cycles at 5 C. This strategy provides a unique flexible tent‐like interface to achieve stable lithium metal anode. [ABSTRACT FROM AUTHOR]

Low‐dimensional ultrawide bandgap semiconductors demonstrate great potential in fabricating solar‐blind ultraviolet photodetectors. However, the widespread use of detectors is still limited by the low responsivity, large noise, and dark current, and especially few detectors can fulfill the solar‐blind ultraviolet detection and the polarization dependence simultaneously. Herein, a polarization sensitive solar‐blind ultraviolet photodetector based on ultrathin KNb3O8 nanobelts synthesized via chemical vapor deposition growth, is reported. By selecting suitable substrate and tuning the growth temperature, the nonlayered KNb3O8 crystal is grown into the quasi‐1D ultrathin nanobelt with thickness in the range of 4.8–120 nm. Density functional theory calculations and experimental results indicate that the ultrathin KNb3O8 nanobelt possesses an ultrawide bandgap (4.15 eV) as well as unusual in‐plane structural anisotropy. Benefiting from the above features, the ultrathin KNb3O8 nanobelt‐based device exhibits superior photodetection performances with high responsivity (30 A W−1), high detectivity (5.95 × 1011 Jones), and ultralow dark current (7.1 × 10−15 A) in the solar‐blind ultraviolet region (230–280 nm). In addition, the KNb3O8 photodetector displays strong polarization sensitive photoresponse with a linear dichroic ratio of 1.62 at 254 nm. With these remarkable features, the ultrathin KNb3O8 nanobelt provides great opportunities for designing the next‐generation multifunctional solar‐blind ultraviolet optoelectronic devices. [ABSTRACT FROM AUTHOR]