Large Piezoelectricity Induced by Internal Stress in (K,Na)NbO3 Single Crystals.

Achieving a high piezoelectric response and excellent stability is essential for practical applications of ferroelectric materials. Herein, large piezoelectricity of d33 = 167 pC/N and kt = 0.52 is found in a K0.7Na0.3NbO3 lead-free ferroelectric single crystal without poling, which is comparable to the artificially poled KNN crystals. The large piezoelectricity is maintained up to 196 °C, showing excellent thermal stability. It was demonstrated that the high piezoelectricity is associated with strong self-polarization in the crystals. The strong internal stress formed during crystal growth gives a preferred spontaneous polarization orientation, resulting in a net macro total polarization. In addition, the internal stress also pins domain wall motions and provides a "restoring force" for the domain switching. This work provides a strategy for designing and optimizing the piezoelectric performance of ferroelectric materials.

Associations of gallbladder and gallstone parameters with clinical outcomes in patients with cirrhosis.

Background: Morphologic changes in the gallbladder and gallstones are common in cirrhotic patients, but their associations with outcomes of cirrhotic patients are unclear. Methods: We retrospectively enrolled 206 cirrhotic patients and measured their gallbladder length and width, gallbladder wall thickness, presence of gallstones, and gallstones' length and width in axial contrast-enhanced computed tomography (CT) images. X-tile software was utilized to calculate the optimal cutoff values of these parameters for evaluating survival and hepatic decompensation events in the cirrhosis group. Their associations with survival were explored by Cox regression analyses and Kaplan-Meier curve analyses. Their associations with hepatic decompensation events were evaluated by competing risk analyses and Nelson-Aalen cumulative risk curve analyses where death was a competing event. Results: Cirrhotic patients with gallbladder length < 72 mm had a significantly higher cumulative survival rate than those with a length of ≥ 72 mm (P = 0.049 by log-rank test), but gallbladder width, gallbladder wall thickness, presence of gallstones, and gallstones' length and width were not significantly associated with survival (P = 0.10, P = 0.14, P = 0.97, P = 0.73, and P = 0.73 by log-rank tests, respectively). Cirrhotic patients with gallbladder wall thickness < 3.4 mm had a significantly lower cumulative rate of hepatic decompensation events than those with a wall thickness of ≥ 3.4 mm (P = 0.02 by Gray's test), but gallbladder length and width, presence of gallstones, and gallstones' length and width were not significantly associated with hepatic decompensation events (P = 0.15, P = 0.15, P = 0.54, P = 0.76, and P = 0.54 by Gray's tests, respectively). Conclusion: Changes in gallbladder length and gallbladder wall thickness, rather than gallstone parameters, may be in parallel with the long-term outcomes of cirrhotic patients.

The effect of autophagy on hemoporfin-mediated photodynamic therapy in human umbilical vein endothelial cells.

SIGNIFICANCE: Hemoporfin-mediated photodynamic therapy (HMME-PDT) has been recognized as a safe and effective treatment for port wine stain (PWS). However, some patients show limited improvement even after multiple treatments. Herein, we aim to explore the effect of autophagy on HMME-PDT in human umbilical vein endothelial cells (HUVECs), so as to provide theoretical basis and treatment strategies to enhance clinical effectiveness. METHODS: Establish the in vitro HMME-PDT system by HUVECs. Apoptosis and necrosis were identified by Annexin Ⅴ-FITC/PI flow cytometry, and autophagy flux was detected by monitoring RFP-GFP-LC3 under the fluorescence microscope. Hydroxychloroquine and rapamycin were employed in the mechanism study. Specifically, the certain genes and proteins were qualified by qPCR and Western Blot, respectively. The cytotoxicity was measured by CCK-8, VEGF-A secretion was determined by ELISA, and the tube formation of HUVECs was observed by angiogenesis assay. RESULTS: In vitro experiments revealed that autophagy and apoptosis coexisted in HUVECs treated by HMME-PDT. Apoptosis was dominant in early stage, while autophagy gradually increased in the middle and late stage. AMPK, AKT and mTOR participated in the regulation of autophagy induced by HMME-PDT, in which AMPK was positive regulation, while AKT and mTOR were negative regulation. Hydroxychloroquine could not inhibit HMME-PDT-induced autophagy, but capable of blocking the fusion of autophagosomes with lysosome. Rapamycin might cooperate with HMME-PDT to enhance autophagy in HUVECs, leading to increased cytotoxicity, reduced VEGF-A secretion, and weakened angiogenesis ability. CONCLUSIONS: Both autophagy and apoptosis contribute to HMME-PDT-induced HUVECs death. Pretreatment of HUVECs with rapamycin to induce autophagy might enhance the photodynamic killing effect of HMME-PDT on HUVECs. The combination of Rapamycin and HMME-PDT is expected to further improve the clinical efficacy.

Effective treatment of corticosteroid-induced facial erythema using fractional radiofrequency microneedling.

OBJECTIVES: To investigate the efficacy of Fractional Radiofrequency Microneedling (FRM) in treating corticosteroid-induced facial erythema. METHODS: A retrospective study was conducted involving eight patients diagnosed as corticosteroid-induced facial erythema. Each patient underwent a single session of FRM. Evaluative measures included Clinician's Erythema Assessment (CEA), Patient's Self-Assessment (PSA), assessment of telangiectasia severity, procedure-associated pain (10-point scale), patient satisfaction (3-point scale) and secondary outcomes. RESULTS: The study found a 75% success rate and 100% effectiveness rate in alleviating erythema symptoms. CEA and PSA scores decreased by 67.7% and 78.1%, respectively. No cases of erythema rebound were recorded during the 3-month follow-up period. CONCLUSIONS: FRM demonstrated effectiveness and safety in treating facial erythema, offering promising advancement in dermatologic therapeutics.

Association of echocardiography-related parameters with the prognosis of decompensated cirrhosis: a retrospective cohort study.

BACKGROUND: Cardiac morphology and function, which are conventionally evaluated by echocardiography, are often abnormal in decompensated cirrhosis. We aimed to evaluate the association of echocardiography-related parameters with prognosis in cirrhosis. METHODS: This retrospective study included 104 decompensated cirrhotic patients, in whom cardiac structure and function were measured by echocardiography, including mitral inflow early diastolic velocity/mitral inflow late diastolic velocity (E/A), left atrium diameter, left ventricular end-diastolic dimension, interventricular septal thickness, left ventricular posterior wall thickness, right atrial transverse diameter, right atrial longitudinal diameter, right ventricular dimension (RVD), stroke volume, cardiac output, left ventricular ejection fraction, and fractional shortening. Cox regression and competing risk analyses and Kaplan-Meier and Nelson-Aalen cumulative risk curves were used to evaluate their associations with further decompensation and death in cirrhotic patients, if appropriate. RESULTS: Lower RVD was a predictor of further decompensation in Cox regression (adjusted by Child-Pugh score: p = 0.138; adjusted by MELD score: p = 0.034) and competing risk analyses (p = 0.003), and RVD ≤17 mm was significantly associated with higher cumulative incidence of further decompensation in Kaplan-Meier (p = 0.002) and Nelson-Aalen cumulative risk curves (p = 0.002). E/A ≤ 0.8 was a significant predictor of death in Cox regression (adjusted by Child-Pugh score: p = 0.041; adjusted by MELD score: p = 0.045) and competing risk analyses (p = 0.024), and E/A ≤ 0.8 was significantly associated with higher cumulative incidence of death in Kaplan-Meier (p = 0.023) and Nelson-Aalen cumulative risk curves (p = 0.024). Other echocardiography-related parameters were not significantly associated with further decompensation or death. CONCLUSION: RVD and E/A may be considered for the prognostic assessment of decompensated cirrhosis.

High-Performance Industrial-Grade CsPbBr3 Single Crystal by Solid-Liquid Interface Engineering.

All-inorganic metal halide perovskite CsPbBr3 crystal is regarded as an attractive alternative to high purity Ge and CdZnTe for room temperature γ-ray detection. However, high γ-ray resolution is only observable in small CsPbBr3 crystal; more practical and deployable large crystal exhibits very low, and even no detection efficiency, thereby thwarting prospects for cost-effective room temperature γ-ray detection. The poor performance of large crystal is attributed to the unexpected secondary phase inclusion during crystal growth, which traps the generated carriers. Here, the solid-liquid interface during crystal growth is engineered by optimizing the temperature gradient and growth velocity. This minimizes the unfavorable formation of the secondary phase, leading to industrial-grade crystals with a diameter of 30 mm. This excellent-quality crystal exhibits remarkably high carrier mobility of 35.4 cm2 V-1 s-1 and resolves the peak of 137 Cs@ 662 keV γ-ray at an energy resolution of 9.91%. These values are the highest among previously reported large crystals.

Efficacy of diet restriction with or without probiotic for treatment of patients with IBS-D: Phase I-II clinical trial.

BACKGROUND AND AIM: Diet is a major contributor to irritable bowel syndrome (IBS) and is also a powerful tool for treatment of IBS. This study compared two diets and explored the effectiveness of the diets when combined with a probiotic for treatment of IBS-D patients. METHODS: Phase I, patients were randomized into groups; control, cold/spicy/fried restricted diet (CSF res diet), IgG positive restricted diet (IgG res diet), and a combination both diets (CSF + IgG res diet). Phase II, patients were randomized into IgG res diet + placebo and IgG res diet + probiotic. Both interventions were 12 weeks in duration. Symptom Severity Scale (IBS-D-SSS) and IgG titer were assessed at the beginning and the end of the study. RESULTS: Totals of 214 and 167 patients completed the two parts of the study, respectively. After intervention, IBS-D-SSS and TIgG grade were significantly improved compared to baseline, with results similar to the control group. In general, there were decreases in IBS-D-SSS and TIgG grade that were significantly different among the groups. There were exceptions; no differences were observed for IBS-D-SSS between the IgG res diet and CSF + IgG res diet, or TIgG grade between the CSF res diet, IgG res diet, and CSF + IgG res diet. However, the CSF res diet and IgG res diet had a synergistic effect that decreased IBS-D-SSS and TIgG titer, with a greater contribution by the IgG res diet. Therefore, we evaluated the IgG res diet with either placebo or probiotic and found that IBS-D-SSS and TIgG grade decreased from baseline. There was a significant decrease in IBS-D-SSS with the probiotic but TIgG grade was not significantly different between the IgG diet + placebo and IgG diet + probiotic diet. CONCLUSIONS: Both the CSF res diet and IgG res diet improved IBS symptoms and demonstrated synergy, although the IgG res diet had a greater contribution. Further, when intolerant foods cannot be eliminated from a diet, avoiding uncooked, cold, spicy, fried, and alcoholic foods is a superior choice. The IgG res diet combined with Bifidobacteria was the best dietary choice and may function though a non-IgG pathway.

Relapsing immunoglobulin G4-related sclerosing cholangitis during maintenance treatment with low-dose steroids: a case report.

Background: Immunoglobulin G4-related sclerosing cholangitis (IgG4-SC) often has a good response to initial steroid therapy, but a high relapse rate during follow-up. Knowledge about the predictors and treatment strategy of relapsing IgG4-SC is of great significance. Case Description: In this paper, we reported that a 57-year-old male was diagnosed with IgG4-SC accompanied by type 1 autoimmune pancreatitis (AIP) at the first onset of his diseases and had a good response to steroid therapy. However, during low-dose steroids maintenance therapy, IgG4-SC relapsed with clinical presentations related to severe bile duct stricture, but improved rapidly after re-administration of full-dose steroids, accompanied by resolution of jaundice, improvement of intrahepatic and extrahepatic bile duct stricture, and gradual recovery of liver function. At the last follow-up in December 2021, he was still stable with methylprednisolone tablets at 4 mg/day. Conclusions: IgG4-SC is likely to relapse in patients who have high serum IgG4 level at initial onset and receive low-dose steroids maintenance treatment. The predictors of disease relapse also include steroids interruption, more severe bile duct stricture, long duration from diagnosis to treatment, history of allergy, and high serum tumor necrosis factor-alpha (TNF-alpha) and soluble interleukin-2 receptor (sIL-2R) levels. Re-administration or up-dose of steroids, immunosuppressors, and rituximab are effective for treating relapsing disease.

U-shaped relationship between subcutaneous adipose tissue index and mortality in liver cirrhosis.

BACKGROUND: Subcutaneous and visceral adipose tissues are important body components, but their effects on the mortality in patients with liver cirrhosis remain controversial based on the current evidence. METHODS: We retrospectively identified 372 eligible patients in whom subcutaneous adipose tissue index (SATI) and visceral adipose tissue index (VATI) could be measured by computed tomography images at the third lumbar vertebra. The association of SATI and VATI with the risk of death was evaluated on a continuous scale with restricted cubic spline curves based on Cox proportional hazards models. Cumulative probability of mortality was estimated by Nelson-Aalen cumulative risk curve analyses. Independent predictors of death were evaluated by competing risk analyses after adjusting for age, sex, and model for end-stage liver disease score. RESULTS: Majority of patients were male (69.4%) with a mean age of 55.40 ± 10.68 years. SATI had a U-shaped association with mortality (P for non-linearity <0.001). Cutoff values of SATI were 19.7 and 51.8 cm2 /m2 at the points where hazard ratios were just <1.2. SATI was categorized as low (<19.7 cm2 /m2 ), moderate (19.7-51.8 cm2 /m2 ), and high (>51.8 cm2 /m2 ) level. There was no significant difference in the cumulative probability of mortality between low versus moderate SATI groups (Gray's test, P = 0.052) and high versus moderate SATI groups (Gray's test, P = 0.054). Competing risk analyses demonstrated that low SATI could increase the mortality compared with moderate SATI (subdistribution hazard ratio [sHR] = 1.66, 95% confidence interval [CI]: 0.992-2.78, P = 0.054) and was an independent predictor of death (sHR = 1.86, 95% CI: 1.059-3.28, P = 0.031). Competing risk analyses also demonstrated that high SATI could significantly increase the mortality compared with moderate SATI (sHR = 1.6, 95% CI: 1-2.54, P = 0.049), and was an independent predictor of death (sHR = 2.007, 95% CI: 1.195-3.37, P = 0.0085). VATI had an irregularly shaped association with mortality (P for non-linearity <0.001). Cutoff values of VATI were 9.8 and 40.2 cm2 /m2 at the points where hazard ratios were just <1.2. VATI was categorized as low (<9.8 cm2 /m2 ), moderate (9.8-40.2 cm2 /m2 ), and high (>40.2 cm2 /m2 ) level. There was no significant difference in the cumulative probability of mortality between low versus moderate VATI groups (Gray's test, P = 0.381) and high versus moderate VATI groups (Gray's test, P = 0.787). Competing risk analyses demonstrated that neither low (sHR = 1.27, 95% CI: 0.599-2.7, P = 0.53) nor high VATI (sHR = 0.848, 95% CI: 0.539-1.34, P = 0.48) was an independent predictor of death compared with moderate VATI. CONCLUSIONS: Both excessive deficiency and accumulation of subcutaneous adipose tissues negatively influence the outcomes of cirrhotic patients.

Improved Crystallization Quality of FAPbBr3 Single Crystals by a Seeded Solution Method.

Solution-grown hybrid perovskite, FAPbBr3, has attracted great attentions recently due to its inspiring optoelectronic properties and low-cost preparation method. However, challenges of solution growth for FAPbBr3 bulk crystals remain yet, such as uncontrollable crystalline morphologies, irregular shapes, and limited crystal sizes, which are attributed to the dense crystallization nucleus. In this work, we investigate the effects of growth conditions and seed behaviors on the crystallization quality and the yield of FAPbBr3 single crystals. First, the spontaneous nucleation is tailored by optimizing the precursor concentration and heating rate. Furthermore, the seeded crystals are introduced to solve the issues related to the morphology and the yield of single crystals. Based on the above-mentioned investigations, an optimized growth method, a seeded solution method, under a heating rate of 0.1 °C/h is proposed, and centimeter-scale FAPbBr3 single crystals with a very narrow FWHM of high-resolution X-ray diffraction rocking curves and a high yield of ∼100% of single crystals are obtained. The resulting FAPbBr3 single crystal exhibits a bulk resistivity of 3.42 × 109 Ω·cm and a superior ION/IOFF ratio over 104 under 405 nm light at a bias of 10 V. Finally, the pulse height spectra with an energy resolution of ∼21.4% are also achieved based on an AZO/FAPbBr3/Au detector, illuminated using an uncollimated 241Am@5.49 MeV α-particle source at room temperature. This modified seeded solution method shows great potential in preparing high-quality and high-yield perovskite single crystals.

Oriented preparation of Large-Area uniform Cs2TeI6 perovskite film for high performance X-ray detector.

Large-area flexible perovskite films are attracting widespread research interest for applications in wearable solar cells, portable photodetectors, bendable X-ray imaging detectors and other implantable optoelectronic devices. In this work, a facile mobile platform assisted electrospray method is developed to prepare large-area (100 cm2) lead-free Cs2TeI6 film on flexible polyimide substrate. The spraying parameters are coupled with the growth temperature to achieve a dynamic balance. The as-prepared film by optimized process shows high uniformity in grain size, thickness and X-ray response without pinholes and cracks. Moreover, oriented nucleation is more likely to occur on the flexible organic substrates for less growth stress and mismatch stress, leading to preferred (222) plane orientation. X-ray detectors prepared with the films exhibit a resistivity of 1.9 × 1011 Ω·cm, an X-ray sensitivity of 226.8 µC⋅Gyair-1⋅cm-2 and a transient response rise time as fast as 42 ms under 50 kV X-ray at an electrical field of 6.67 × 103 V·mm-1. The modified electrospray method shows great potential applications for large-area devices of radiography, solar cell and other optoelectronic devices.

Template directed perovskite X-ray detectors towards low ionic migration and low interpixel cross talking.

The metal halide perovskites exhibit excellent performance as the direct X-ray detectors owing to their strong absorption capability, long carrier lifetime and diffusion length, radiation ruggedness, etc. For imaging applications, the ionic migration of perovskites and charge sharing effect between the adjacent pixels have a significantly negative impact on the spatial resolution. Herein, for the first time, the porous anodic aluminum oxides (AAO) have been used as a template to grow the CsPbBr2I thick film for the direct X-ray detection. Benefiting from the oxygen passivation effect, the activation energy for ionic migration has been observed to increase to 0.701 eV, whereas the dark current drift (1.01 × 10-5 nA cm-1s-1V-1) is one to two orders of magnitude lower than the other lead halide perovskite single crystals and films. Moreover, the AAO insulating wall effectively blocks the charge diffusion effect across a pixel pitch of 10 µm. Overall, the findings reported in this study open a new route for reducing the ionic migration and pixel crosstalk, thus, bringing the perovskite X-ray detectors close to the practical applications.

Endoscopic treatment for gastric antral vascular ectasia.

Gastric antral vascular ectasia (GAVE) is one of the uncommon causes of upper gastrointestinal bleeding. Major treatment of GAVE includes pharmacotherapy, endoscopy, and surgery. The efficacy and safety of pharmacotherapy have not been sufficiently confirmed; and surgery is just considered when conservative treatment is ineffective. By comparison, endoscopy is a common treatment option for GAVE. This paper reviews the currently used endoscopic approaches for GAVE, mainly including argon plasma coagulation (APC), radiofrequency ablation (RFA), and endoscopic band ligation (EBL). It also summarizes their efficacy and procedure-related adverse events. The endoscopic success rate of APC is 40-100%; however, APC needs several treatment sessions, with a high recurrence rate of 10-78.9%. The endoscopic success rates of RFA and EBL are 90-100% and 77.8-100%, respectively; and their recurrence rates are 21.4-33.3% and 8.3-48.1%, respectively. Hyperplastic gastric polyps and sepsis are major adverse events of APC and RFA; and Mallory-Weiss syndrome is occasionally observed after APC. Adverse events of EBL are rare and mild, such as nausea, vomiting, esophageal or abdominal pain, and hyperplastic polyps. APC is often considered as the first-line choice of endoscopic treatment for GAVE. RFA and EBL have been increasingly used as alternatives in patients with refractory GAVE. A high recurrence of GAVE after endoscopic treatment should be fully recognized and cautiously managed by follow-up endoscopy. In future, a head-to-head comparison of different endoscopic approaches for GAVE is warranted.

Focal nodular hyperplasia mimicking hepatocellular adenoma and carcinoma in two cases.

Focal nodular hyperplasia (FNH) is a solid benign tumor of the liver, predominantly in young women. A correct diagnosis of FNH is essential for making appropriate clinical decisions and avoiding unnecessary liver resection. Herein, we reported that two male cases with FNH, who initially presented with persistent abdominal discomfort, were misdiagnosed with hepatocellular adenoma (HCA) and hepatocellular carcinoma (HCC) on contrast-enhanced magnetic resonance imaging and computed tomography scans, respectively. After surgery, a histological diagnosis of FNH was finally established. In this paper, we also reviewed the knowledge regarding diagnosis and differential diagnosis of FNH on imaging examinations, which are helpful for avoiding misdiagnoses and guiding clinical interventions.

High-Stability Flexible X-ray Detectors Based on Lead-Free Halide Perovskite Cs2TeI6 Films.

Normal flat panel X-ray detectors are confined in imaging of curved surfaces and three-dimensional objects. Except that, their rigid panels provide uncomfortable user experience in medical diagnosis. Here, we report a flexible X-ray detector fabricated by the combination of a lead-free Cs2TeI6 perovskite film and a polyimide (PI) substrate. High-quality Cs2TeI6 polycrystalline films are prepared by a low-temperature electrospraying method. The resistivity even remained at the level of 1011 Ω·cm after 100 cycles of bending tests with a low bending radius of 10 mm. The resulting flexible Cs2TeI6 detectors exhibit better response stability than those based on rigid SnO2:F glass (FTO), which is attributed to the superior crystallization of films and the growth stress relief of flexible substrates. Furthermore, an X-ray sensitivity of 76.27 µC·Gyair-1·cm-2 and a detection limit of 0.17 µGyair·s-1 are achieved. A series of distortion-free clear X-ray images are obtained for objects with different materials and densities. These findings provide insights into flexible X-ray detectors based on perovskite films and motivate research in wearable X-ray detectors for medical radiography and dose monitoring.

Brunner's Gland Hamartoma of the Duodenum: A Literature Review.

Brunner's gland hamartoma is a benign tumor of the duodenum, but has malignant potential with a very low risk of progression into adenocarcinoma. It is uncommon with a frequency of less than 1.0% among the primary tumors of the small intestine. In addition, its clinical manifestations are nonspecific, etiology remains unclear, and treatment strategy needs to be further refined. This literature review mainly discusses the epidemiology, clinical features, possible etiology and pathogenesis, diagnostic methods, malignant potential, treatment, and prognosis of Brunner's gland hamartoma.

Safety and effectiveness of 5-aminolevulinic acid photodynamic therapy combined with fractional micro-plasma radio-frequency treatment for verrucous epidermal nevus: A retrospective study with long-term follow-up.

Verrucous epidermal nevus (VEN) is a benign skin disease that seriously affects appearance. Numerous therapeutic methods have been tried with varying results. However, there are few reports on the treatment of VEN by photodynamic therapy (PDT). This study aimed to evaluate the efficacy and adverse effects of 5-aminolevulinic acid (ALA)-PDT in VEN treatment with a long-term follow-up. A total of 16 patients with VEN received ALA-PDT and were followed up for more than 1 year to observe the treatment effects, adverse reactions, and patients' satisfaction. Complete improvement of lesions was observed in 11 patients (three to six sessions of ALA-PDT). Two patients obtained 90-99% improvement (five sessions) and 50-89% improvement in three patients (three to six sessions). They were satisfied with the treatment effects, with an average satisfaction of 4.19/5 (±0.91). Long-term follow-up ranging 14-50 months showed a low recurrence rate (2/16) and no scar left after ALA-PDT. The results demonstrate that ALA-PDT is an effective and safe therapy in treating VEN with mild adverse reactions and a low risk of scar formation.

Recycling of Lignin and Si Waste for Advanced Si/C Battery Anodes.

The ever-increasing silicon photovoltaics industry produces a huge annual production of silicon waste (2.03 × 105 tons in 2019), while lignin is one of the main waste materials in the traditional paper industry (7.0 × 107 tons annually), which lead to not only enormous wastage of resources but also serious environment pollution. Lithium-ion batteries (LIBs) are the dominating power sources for portable electronics and electric vehicles. Silicon (Si)-based material is the most promising anode choice for the next-generation high-energy-density LIBs due to its much higher capacity than the commercial graphite anode. Here, we proposed the use of these silicon and lignin waste as sustainable raw materials to fabricate high-capacity silicon/carbon (Si/C) anode materials for LIBs via a facile coprecipitation method utilizing electrostatic attracting force, followed by a thermal annealing process. The as-achieved Si/C composite featured an advanced material structure with micrometer-sized secondary particles and Si nanoparticles embedded in the carbon matrix, which could tackle the inherent challenges of Si materials, including low conductivity and large volume change during the lithiation/delithiation processes. As expected, the obtained Si/C composite displayed an initial charge capacity of 1016.8 mAh g-1, which was 3 times that of a commercial graphite anode in the state-of-the-art LIBs, as well as a high capacity retention of 74.5% at 0.2 A g-1 after 100 cycles. In addition, this Si/C composite delivered superior rate capability with a high capacity of 575.9 mAh g-1 at 2 A g-1, 63.4% of the capacity at 0.2 A g-1. The utilization of industrial Si and lignin waste provides a sustainable route for the fabrication of advanced high-capacity anode materials for the next-generation LIBs with high economic and environmental feasibility.

Anisotropic dielectric behavior of layered perovskite-like Cs3Bi2I9 crystals in the terahertz region.

The ternary metal halide perovskites have gradually attracted attention for application in the optoelectronic field, owing to their tunable crystal structure and appropriate bandgap. Lead free Cs3Bi2I9 perovskite, with a 0D layered structure containing molecular [Bi2I9]3- dimers, exhibits prominent optical and electrical anisotropies. Here, the anisotropic properties of the Cs3Bi2I9 crystals were evaluated using terahertz time-domain spectroscopy (THz-TDS); meanwhile, the effect of phonon vibration on the THz transmission was confirmed using density functional perturbation theory (DFPT). Accordingly, the refractive index and extinction coefficient are estimated using THz-TDS, thanks to the high transmission in the range of 0.2-0.9 THz. The anisotropic refractive index was observed for the Cs3Bi2I9 crystals, and was found to be 3.2-3.7 for the (100) plane (CBI(100)) in contrast to 2.8-3.2 for the (001) plane (CBI(001)). Furthermore, the Lorentz model was employed to extract the dielectric constant of Cs3Bi2I9, in which anisotropy is obviously indicated by the static dielectric constant and the high-frequency dielectric constant. These anisotropic behaviors are determined by the dipole moment, which is attributed to the anisotropic packing density of [Bi2I9]3- dimers. This study is significant and provides a deeper insight into the anisotropic photoelectric properties of Cs3Bi2I9, thus contributing to the development of metal halide perovskites in the field of optoelectronics.

Efficient PbSe Colloidal Quantum Dot Solar Cells Using SnO2 as a Buffer Layer.

PbSe colloidal quantum dots (CQDs) are widely used in solar cells because of their tunable band gap, solution processability, and efficient multiple exciton generation effect. The most efficient PbSe CQD solar cells use high-temperature-processed ZnO as the electron transport layer (ETL), limiting their applications in flexible photovoltaics. Currently, low-temperature solution-processed SnO2 has been demonstrated as an efficient ETL for high-efficient PbS CQD and perovskite solar cells because of less parasitic light absorption and higher electron mobility. Herein, we introduce low-temperature solution-processed SnO2 as ETL for PbSe CQD solar cells, and fabricate the PbSe CQD absorber layer with a one-step spin-coating method. The champion device with the structure of FTO (SnO2:F)/SnO2/PbSe-PbI2/PbS-EDT (1,2-ethanedithiol)/Au achieves a high open-circuit voltage of 577.1 mV, a short-circuit current density of 24.87 mA cm-2, a fill factor of 67%, and an impressive power conversion efficiency of 9.67%. Our results pave the way for the development of low-temperature flexible PbSe CQD solar cells.