Development of Semitransparent UV Photodetector Based on PTB7-Th:PCBM Composite Using the Cost-effective Fabrication Method

This article presents a semitransparent ultraviolet (UV) sandwich-surface type sensor based on PTB7-Th: PCBM composite. The ultraviolet (UV) transparency of 29% was achieved through a cost-effective drop-cast fabrication method. The variation in UV intensity (0 to 20,000 pW/cm2) and frequency (100 Hz, 1 kHz, 10 kHz, 100 kHz, and 200 kHz) was carried out, and variation of impedance and capacitance has been studied. After a comprehensive analysis under specific UV strength and frequency, a considerable increase in capacitance and a significant decrease in impedance were observed. The generation of electron-hole pair relates such findings by increasing the concentration of charges, combined potential, and possible frequency dependence of charge mobility under UV-irradiation. The UV sensor can be used for measuring the UV and visible light intensities. They have applications in the field of electronics and photonics.The authors would like to acknowledge the support of the Higher Education Commission Pakistan, Pakistan Science Foundation, GIK Institute of Engineering Sciences and Technology of Pakistan for providing the necessary research facilities. The authors acknowledge the support of Dr. Rashid Ali for XRD patterns and Dr. Imran Khan for AFM images

A La2O3/MXene composite electrode for supercapacitors with improved capacitance and cycling performance

ABSTRACTDeveloping efficient electrode materials is a key towards high power electrochemical energy storage devices. Two-dimensional (2D) MXene shows excellent conductivity and electrochemical performance among other materials. However, the restacking of MXene layers may degrade their specific capacity and cycling performance. Considering this challenge, here we have designed a composite made of 2D MXene nanosheets and lanthanum oxide (La2O3) nanoparticles to overcome the limitations. The bifunctionality of La2O3 nanoparticles prevents the restacking of MXene layers and enhances the electrochemical properties of the electrode due to its good Faradic characteristics. The specific capacitance of the La2O3/MXene composite electrode is 366 F/g at 1 A/g, which is 4.5 and 3 times higher than those of the individual La2O3 and MXene. The composite electrode displays a capacitance retention of 96% after 1,000 cycles, which is due to synergistic effects between the two components and indicates the potential of La2O3/MXene composite for supercapacitors

Guided Electro-Optical Switching of Small Graphene Oxide Particles by Larger Ones in Aqueous Dispersion

Although the large Kerr coefficient of aqueous graphene oxide (GO) dispersions is quite attractive for electro-optical applications with low power consumption, the maximum birefringence of GO dispersions is not sufficiently high for actual display applications. Here we report that adding a small amount of larger GO particles (about 4 μm) into a high-concentration dispersion of small GO (about 0.2 μm) can improve the electro-optical sensitivity to an electric field and also the maximum birefringence. Large GOs induce the ordering of small particles and enhance the electro-optical switching. Large GOs have higher polarizability and are easily driven under an applied electric field, and the rotational motion of large GO particles leads to switching of surrounding small GO particles, improving the electro-optical performance. The binary mixture can overcome the limitations of pure dispersions of large GO or small GO particles; the former has high interparticle interaction, and the latter has low sensitivity to an electric field

Self-reported health and smoking status, and body mass index: a case-control comparison based on GEN SCRIP (GENetics of SChizophRenia In Pakistan) data

Introduction Individuals with schizophrenia are at a high risk of physical health comorbidities and premature mortality. Cardiovascular and metabolic causes are an important contributor. There are gaps in monitoring, documenting and managing these physical health comorbidities. Because of their condition, patients themselves may not be aware of these comorbidities and may not be able to follow a lifestyle that prevents and manages the complications. In many low-income and middle-income countries including Pakistan, the bulk of the burden of care for those struggling with schizophrenia falls on the families.Objectives To determine the rate of self-reported physical health disorders and risk factors, like body mass index (BMI) and smoking, associated with cardiovascular and metabolic disorders in cases of schizophrenia compared with a group of mentally healthy controls.Design A case-controlled, cross-sectional multicentre study of patients with schizophrenia in Pakistan.Settings Multiple data collection sites across the country for patients, that is, public and private psychiatric OPDs (out patient departments), specialised psychiatric care facilities, and psychiatric wards of teaching and district level hospitals. Healthy controls were enrolled from the community.Participants We report a total of 6838 participants’ data with (N 3411 (49.9%)) cases of schizophrenia compared with a group of healthy controls (N 3427 (50.1%)).Results BMI (OR 0.98 (CI 0.97 to 0.99), p=0.0025), and the rate of smoking is higher in patients with schizophrenia than in controls. Problems with vision (OR 0.13 (0.08 to 0.2), joint pain (OR 0.18 (0.07 to 0.44)) and high cholesterol (OR 0.13 (0.05 to 0.35)) have higher reported prevalence in controls. The cases describe more physical health disorders in the category ‘other’ (OR 4.65 (3.01 to 7.18)). This captures residual disorders not listed in the questionnaire.Conclusions Participants with schizophrenia in comparison with controls report more disorders. The access in the ‘other’ category may be a reflection of undiagnosed disorders