Photodetection over a broad spectral range is crucial for optoelectronic applications such as sensing, imaging, and communication. Herein, a high‐performance ultra‐broadband photodetector based on PdSe2 with unique pentagonal atomic structure is reported. The photodetector responds from visible to mid‐infrared range (up to ≈4.05 µm), and operates stably in ambient and at room temperature. It promises improved applications compared to conventional mid‐infrared photodetectors. The highest responsivity and external quantum efficiency achieved are 708 A W−1 and 82 700%, respectively, at the wavelength of 1064 nm. Efficient optical absorption beyond 8 µm is observed, indicating that the photodetection range can extend to longer than 4.05 µm. Owing to the low crystalline symmetry of layered PdSe2, anisotropic properties of the photodetectors are observed. This emerging material shows potential for future infrared optoelectronics and novel devices in which anisotropic properties are desirable.

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Two-dimensional (2D) magnets with intrinsic ferromagnetic/antiferromagnetic (FM/AFM) ordering are highly desirable for future spintronic devices. However, the direct growth of their crystals is in its infancy. Here we report a chemical vapor deposition approach to controllably grow layered tetragonal and non-layered hexagonal FeTe nanoplates with their thicknesses down to 3.6 and 2.8 nm, respectively. Moreover, transport measurements reveal these obtained FeTe nanoflakes show a thickness-dependent magnetic transition. Antiferromagnetic tetragonal FeTe with the Néel temperature ( T N ) gradually decreases from 70 to 45 K as the thickness declines from 32 to 5 nm. And ferromagnetic hexagonal FeTe is accompanied by a drop of the Curie temperature ( T C ) from 220 K (30 nm) to 170 K (4 nm). Theoretical calculations indicate that the ferromagnetic order in hexagonal FeTe is originated from its concomitant lattice distortion and Stoner instability. This study highlights its potential applications in future spintronic devices.

Recently, the development of polydopamine (PDA) has demonstrated many excellent performances such as free radical scavenging, UV shielding, photothermal conversion, and biocompatibility. These unique properties make PDA widely designed as...

Polydopamine (PDA), as the most typical kind of synthetic melanins, possesses similar interesting properties, such as antioxidation, photoprotection, metal chelation, and energy dissipation. During the past a few years, PDA...

Smart hydrogels with multistimuli responsiveness have been increasingly exploited as soft matters for biomedical applications in drug delivery, tissue engineering, and bioactuators. While many of the effects have been well documented, the facile fabrication of multiresponsive hydrogels with specific functionality is met with profound challenges, particularly in the redundant synthesis of macromolecular building blocks and the integration of multiple dynamic linkages to construct hydrogel networks. To address this issue, herein, we report a simple and rapid fabrication of smart hydrogels by direct gelation of all naturally occurring building blocks including aminoglycosides, protocatechualdehyde, and Fe(III) via two types of dynamic chemical bonds. The resulting smart hydrogels could perform excellent dynamic features and promising multiresponsiveness to different stimuli including temperature, light, pH, redox, and electricity, and also exhibited high antibacterial activities. This study offers new opportunities in the facile preparation of smart hydrogels for a wide range of applications.

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We report the first effort to control the size of polydopamine nanoparticles via adding either strong free radical scavengers (i.e. edaravone) or stable free radicals (i.e. PTIO˙) during the polymerization.