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Quantum dots (QDs) often exhibit unique behaviors because the reduction in lateral size leads to stronger quantum confinement effects and a higher surface-to-volume ratio in comparison with larger two-dimensional nanosheets. However, the preparation of homogeneous QDs remains a longstanding challenge. This work reports the preparation of high-yield and ultrasmall tin disulfide (SnS2) QDs by combining top–down and bottom–up approaches. The as-prepared SnS2 QDs have a uniform lateral size of 3.17 ± 0.62 nm and a thicknesses 2.39 ± 0.88 nm. A series of self-powered photoelectrochemical-type photodetectors (PDs) utilizing the SnS2 QDs as photoelectrodes are also constructed. Taking advantage of the tunable bandgaps and high carrier mobility of the SnS2, our PDs achieve a high photocurrent density of 16.38 μA cm−2 and a photoresponsivity of 0.86 mA W−1, and good long-term cycling stability. More importantly, the device can display obvious photoresponse, even at zero bias voltage (max), and greater weak-light sensitivity than previously reported SnS2-based PDs. Density functional theory calculation and optical absorption were employed to reveal the working mechanism of the SnS2 QDs-based PDs. This study highlights the prospective applications of ultrasmall SnS2 QDs and provides a new route towards future design of QDs-based optoelectronic devices.

Quantum dots (QDs) often exhibit unique behaviors because the reduction in lateral size leads to stronger quantum confinement effects and a higher surface-to-volume ratio in comparison with larger two-dimensional nanosheets. However, the preparation of homogeneous QDs remains a longstanding challenge. This work reports the preparation of high-yield and ultrasmall tin disulfide (SnS2) QDs by combining top–down and bottom–up approaches. The as-prepared SnS2 QDs have a uniform lateral size of 3.17 ± 0.62 nm and a thicknesses 2.39 ± 0.88 nm. A series of self-powered photoelectrochemical-type photodetectors (PDs) utilizing the SnS2 QDs as photoelectrodes are also constructed. Taking advantage of the tunable bandgaps and high carrier mobility of the SnS2, our PDs achieve a high photocurrent density of 16.38 μA cm−2 and a photoresponsivity of 0.86 mA W−1, and good long-term cycling stability. More importantly, the device can display obvious photoresponse, even at zero bias voltage (max), and greater weak-light sensitivity than previously reported SnS2-based PDs. Density functional theory calculation and optical absorption were employed to reveal the working mechanism of the SnS2 QDs-based PDs. This study highlights the prospective applications of ultrasmall SnS2 QDs and provides a new route towards future design of QDs-based optoelectronic devices. [ABSTRACT FROM AUTHOR]

The impact of pristine multiwalled carbon nanotubes (MWCNTs),anionic liquid (IL), 1-butyl-3-methylimidazolium hexafluorophosphate[BMIM][PF6], and the ionic liquid-modified MWCNTs (IL-MWCNTs)on the crystallization behavior of melt-crystallized poly(vinylidenefluoride) (PVDF) has been investigated. Pristine MWCNTs accelerate crystallization of PVDF as an efficient nucleation agent, while theformed crystals are mainly nonpolar α crystal form with fewpolar β crystals. Incorporation of only ionic liquid resultsin depression of the PVDF melt crystallization rate due to the miscibilityof IL with PVDF but leads to a higher content of polar crystals (βand γ forms) than MWCNTs. The ionic liquid and MWCNTs show significantsynergetic effects on both the nucleation and the formation of polarcrystals for PVDF by melt crystallization. Addition of IL-MWCNTsnot only improves the MWCNTs dispersion in PVDF matrix but also increasesthe overall crystallization rate of PVDF drastically. More important,the melt-crystallized PVDF nanocomposites with IL-MWCNTs show 100%polar polymorphs but no α crystal forms. To the best of ourknowledge, this is the first report on the achievements of full polarcrystal form in the melt-crystallized PVDF without mechanical deformationor electric field. The IL to MWCNTs ratio and the IL-MWCNTs loadingcontent effects on the crystallization behavior of PVDF in the nanocompositeswere also studied. It is considered that the specific interactionsbetween >CF2with the planar cationic imidazolium ringwrapped on the MWCNTs surface lead to the full zigzag conformationsof PVDF; thus, nucleation in polar crystals (β and γforms) lattice is achieved and full polar crystals are obtained by subsequent crystal growth from the nuclei. [ABSTRACT FROM AUTHOR]

The metal-on-metal (MoM) artificial hip joint is a prosthesis used in early hip arthroplasty, particularly for hip resurfacing and total hip arthroplasty. However, abrasion and corrosion of MoM bearings result in the production of metal ions, such as cobalt and chromium, thereby inducing several complications such as inflammatory pseudotumor, aseptic inflammation, and allergy to metal ions (delayed type IV hypersensitivity). In this case report, we present a patient who was hospitalized for recurrence of a mass in the right inguinal area. In 2010, the patient underwent right MoM total hip arthroplasty for right femoral head necrosis and exhibited a good postoperative recovery. In 2019, the patient experienced pain in the right hip with activity limitation without any evident triggers, and a palpable mass was observed in the right inguinal area. A large periprosthetic mass was resected under general anesthesia, and the patient recovered well after the operation. Based on post-surgery imaging and pathological examinations, the mass was diagnosed as a periprosthetic inflammatory pseudotumor. In 2021, the inflammatory pseudotumor recurred at the same site. He then underwent right total hip revision surgery under epidural anesthesia and recovered well after surgery. No recurrence was noted at moderate follow-up. The incidence of inflammatory pseudotumors is high in MoM hip arthroplasty. Early revision is necessary in patients who meet the indications for revision, while regular postoperative follow-up is crucial., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Min, Xing, Xu, Wei and Fan.)