Highly efficient fiber-shaped organic solar cells toward wearable flexible electronics

Fiber-shaped solar cells(FSCs)show great potential to act as the power source in the wearable electronics field.Due to the unique advantages of the fiber-shaped organic solar cells(FOSCs),such as all-solid-state,ease of fabrication,and environmental friendliness,FOSCs are the strongest candidate among all types of FSCs for wearable electronics.However,the development of FOSCs is seriously lagging behind other types of FSCs.In this work,we demonstrate the efficient FOSCs with non-fullereneacceptors(NFAs)-based light-harvesting materials.The FOSCs present efficiencies exceeding 9%under AM 1.5 G irradiation conditions.The performance influence factors including hole/electron transport layers,active layer,counter electrodes,solvents,and especially,the environmental humidity is systematically studied.The FOSCs not only can easily drive the electrical devices but also can be woven into the textile to charge the smartwatch.The study exhibits the great potential to apply the FOSCs as the power supply source in the wearable electronic field.

Balancing efficiency and transparency in organic transparent photovoltaics

The challenges in transparent photovoltaic(TPV)fields are still that the device transparency and efficiency are difficult to be balanced to meet the requirements of practical applications.In this study,we systematically investigated the interrelationship between photovoltaic film properties,optical transmission,and photovoltaic performances in the near-infrared harvesting organic TPVs.The results indicate that the photovoltaic film thickness determines the TPV’s transparency and meanwhile affects the device efficiency;by contrast,the donor-acceptor ratio only affects device efficiency and has little effect on transparency.By controlling the film thickness and donor-acceptor ratio,the average visible transmission(AVT)of TPVs can be precisely managed in the range of 40%-85%,and the device efficiency can achieve as high as 4.06%and 2.38%while the AVT exceeds 70%and 80%,respectively.Importantly,the large area(~10 cm^(2))TPV modules and ultra-flexible devices were then successfully prepared based on the systematical study.