INTRODUCTION Smoking cessation should be part of tuberculosis (TB) treatment, but a cessation service is not available as part of a routine TB service in most low- and middle-income countries. WHO and The International Union Against Tuberculosis and Lung Disease (The Union) issued a guideline and China implemented a pilot project 5 years ago. This study aimed to determine changes in smoking status among TB patients at 5 years after completion of anti-TB treatment to observe long-term outcome of a smoking cessation project whose baseline characteristics were associated with a relapse of smoking behavior. METHODS A prospective longitudinal study was conducted 5 years after completion of anti-TB treatment to assess changes in patient smoking status against individual baseline data that were entered into a database at the time of TB registration. The patients were tracked by trained village doctors and validated by township health staff. Their smoking status was assessed and entered into the database and analysed. RESULTS Of the 800 TB patients registered at baseline, 650 (81.2%) were tracked. Ninety-one (11.4%) patients died and 59 (7.4%) were lost to follow-up. The rates of remaining non-smoking after 5 years were 82.0%, 63.0%, 49.6%, 43.5% and 30.0%, respectively for non-smokers, ex-smokers, current smokers who received cessation intervention, recent quitters, and current smokers not on a cessation intervention. The odds of smoking relapse were significantly higher for those aged >= 65 years (p=0.003) and registered in Xingguo County (p=0.025). CONCLUSIONS Findings from this study confirmed that non-smokers, ex-smokers and current smokers who received cessation intervention at baseline maintained higher non-smoking rates compared with those who did not receive the intervention. To prevent relapse, intensive cessation support should be given to TB patients aged >= 65 years. TB programme managers need to ensure integration and provision of smoking cessation advice and smoke-free policy in routine TB services.

All-inorganic CsPbI2Br perovskite has attracted increasing attention, owing to its outstanding thermal stability and suitable bandgap for optoelectronic devices. However, the substandard power conversion efficiency (PCE) and large energy loss (E-loss) of CsPbI2Br perovskite solar cells (PSCs) caused by the low quality and high trap density of perovskite films still limit the application of devices. Herein, the post-treatment of evaporating cesium bromide (CsBr) is utilized on top of the perovskite surface to passivate the CsPbI2Br-hole-transporting layer interface and reduce E-loss. The results of microzone photoluminescence indicate that the evaporated CsBr gathered at the grain boundaries of CsPbI2Br layers and Br-enriched perovskites (CsPbIxBr3-x, x < 2) are formed, which can provide protection for CsPbI2Br. Therefore, the gaps between crystal grains are filled up, and the recombination loss of the all-inorganic CsPbI2Br PSCs is reduced accordingly. The champion device exhibits high open-circuit voltage and a PCE of 1.271 V and 16.37%, respectively. This is the highest reported PCE among all-inorganic CsPbI2Br PSCs reported so far. In addition, the stability of CsPbI2Br PSCs is effectively improved by CsBr passivation, and the device without encapsulation can retain 86% of its initial PCE after 1368 h of storage, which is beneficial for practical applications.

Interface modification engineering has been widely used as a flexible and effective method to optimize the performance of perovskite photovoltaic devices. Herein, we adopt NiCl2 as a modifier to passivate the interface at the electron transporting layer (ETL) and perovskite layer to drive high-efficiency perovskite solar cells (PSCs) with increased open circuit voltage (V-oc) and neglectable hysteresis. The devices based on SnO2/NiCl2 ETL achieved a high V-oc (1.17 V) and power conversion efficiency (PCE) (19.46%). The improvement is attributed to the increased energy level of the conduction band minimum (E-CBM) and reduced defect states by NiCl2 interface modification. Our findings provide an effective way to obtain higher V-oc and PCE values as well as neglectable hysteresis for planar PSCs.

Compared with silicon-based solar cells, organic-inorganic hybrid perovskite solar cells (PSCs) possess a distinct advantage, i.e., its application in the flexible field. However, the efficiency of the flexible device is still lower than that of the rigid one. First, it is found that the dense formamidinium (FA)-based perovskite film can be obtained with the help of N-methyl-2-pyrrolidone (NMP) via low pressure-assisted method. In addition, CH3NH3Cl (MACl) as the additive can preferentially form MAPbCl(3-)(x)I(x) perovskite seeds to induce perovskite phase transition and crystal growth. Finally, by using FAI center dot PbI2 center dot NMP+x%MACl as the precursor, i.e., ligand and additive synergetic process, a FA-based perovskite film with a large grain size, high crystallinity, and low trap density is obtained on a flexible substrate under ambient conditions due to the synergetic effect, e.g., MACl can enhance the crystallization of the intermediate phase of FAI center dot PbI2 center dot NMP. As a result, a record efficiency of 19.38% in flexible planar PSCs is achieved, and it can retain about 89% of its initial power conversion efficiency (PCE) after 230 days without encapsulation under ambient conditions. The PCE retains 92% of the initial value after 500 bending cycles with a bending radii of 10 mm. The results show a robust way to fabricate highly efficient flexible PSCs.