Developed graphene/Si Schottky junction solar cells based on the top-window structure

Chemical Vapor Deposition (CVD)-graphene has potentially been integrated with silicon (Si) substrates for developing graphene/n-Si Schottky junction solar cells prepared with the top window structure. However, there are drawbacks to prepared devices such as complex silicon dioxide (SiO2)-etching steps, low fill factors and stability of doped devices. In this work, SiO2 patterns are simply formed using a sputtering process rather than the previous complex method. Additionally, the fill factor for prepared devices is developed by using transferred residue-free multi-graphene layers. The usage of 3 graphene layers improves the power conversion efficiency (PCE) to 7.1%. A recorded PCE of around 17% with a fill factor of 74% is achieved by the HNO3 dopant. To overcome the issue of stability, Poly(methyl methacrylate) as an encapsulated layer is introduced. Hence, the doped devices show great stability for storage in air for 2 weeks, and devices recovered about 95% of their efficiency. This work shows that the developed fabrication process is suitable to develop simple, low cost, stable and efficient graphene/Si Schottky solar cells

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely