A tandem organic solar cell (OSC) is a valid structure to widen the photon response range and suppress the transmission loss and thermalization loss. In the past few years, the development of low‐bandgap materials with broad absorption in long‐wavelength region for back subcells has attracted considerable attention. However, wide‐bandgap materials for front cells that have both high short‐circuit current density (JSC) and open‐circuit voltage (VOC) are scarce. In this work, a new fluorine‐substituted wide‐bandgap small molecule nonfullerene acceptor TfIF‐4FIC is reported, which has an optical bandgap of 1.61 eV. When PBDB‐T‐2F is selected as the donor, the device offers an extremely high VOC of 0.98 V, a high JSC of 17.6 mA cm−2, and a power conversion efficiency of 13.1%. This is the best performing acceptor with such a wide bandgap. More importantly, the energy loss in this combination is 0.63 eV. These properties ensure that PBDB‐T‐2F:TfIF‐4FIC is an ideal candidate for the fabrication of tandem OSCs. When PBDB‐T‐2F:TfIF‐4FIC and PTB7‐Th:PCDTBT:IEICO‐4F are used as the front cell and the back cell to construct tandem solar cells, a PCE of 15% is obtained, which is one of best results reported to date in the field of organic solar cells.

Random conjugated polymers, such as typical polymerized small molecular acceptors (PSMAs), concurrently suffer from the dual batch factors of molecular weights (MWs) and regioregularity, which seriously interfere with the study of the relationship between batch factors and polymer properties. Here, four isomer‐free PSMAs, PA‐5 and three members of a PA‐6 series with low (L), medium (M), and high (H) MWs, in which 5 and 6 define linkage position throughout conjugated backbone, are designed and synthesized to clearly investigate polymer batch effects. These studies reveal that PA‐6‐L and PA‐6‐M have ignorable batch differences within deviations, which deliver comparable maximum efficiencies of 14.81% and 14.99%, respectively. The PA‐6‐H based cell is processed from chlorobenzene with its high boiling point, due to the limited solubility in other common solvents, leading to large‐size phase separation during prolonged film drying process, and thereby inferior performance. In contrast, PA‐5 possesses diverse absorption characteristics, and ordered crystallization, which prompts higher short‐circuit current density and fill factor in the cell. As a result, the corresponding device realizes a photovoltaic performance of 16.11%, which is one of the best binary all‐polymer solar cells in the reported literature to date. This study provides a new insight into complicated batch effects of PSMAs on device performance while avoiding cross‐talk between them.

Background Sepsis biomarkers have limited specificity and sensitivity. Few studies have investigated microRNA (miRNA) biomarkers for sepsis secondary to pneumonia. This study aims to investigate the diagnostic and prognostic values of miRNAs in sepsis secondary to pneumonia. Methods Sepsis 3.0 was used to diagnose sepsis. Screening was performed through the Agilent miRNA chip technology by using the following criteria: p < 0.05, fold ≥2 or < 0.5, or copy number > 50 change. This study recruited 52 patients with pneumonia, including 31 males (59.6%) and 21 females (40.4%), 44 patients with sepsis secondary to pneumonia were diagnosed via Sepsis 3.0 (34 [77.3%] males and 10 [22.7%] females), and 21 healthy controls were used for miRNA verification. The miRNA levels were detected through fluorescence real-time quantitative polymerase chain reaction (qRT-PCR). Results: Fluorescence qRT-PCR detection showed that the miR-7110-5p and miR-223-3p expression levels in both patient groups were upregulated compared with those in the healthy controls. The expression levels differed between patients with pneumonia and those with sepsis secondary to pneumonia. The sensitivity and specificity of miR-7110-5p to differentiate sepsis from healthy controls were 84.2 and 90.5%, whereas those of miR-223-3p were 82.9 and 100%, respectively. Multivariate analysis of variance suggested that the presence of sepsis affected the miR-223-3p level ( p = 0.041), whereas the presence of sepsis ( p = 0.000) and the underlying disease ( p = 0.025) influenced the miR-7110-5p level. Conclusions MiR-223-3p could be utilized to predict sepsis secondary to pneumonia.

Naphthalene diimide (NDI) and perylene diimide (PDI) based polymeric semiconductors with high mobility have shown great promise as electron transport materials (ETMs) in applications such as highperformance polymer solar cells (PSCs) and other optoelectronic devices. However, these NDI and PDI semiconductors usually have limited adjustment of the lowest unoccupied molecular orbital (LUMO) energy levels, which hinders their further use in the organic electronic device. Here, by using various degrees of esterification instead of imide groups, three perylenetetracarboxylic acid derivatives based, self-doped, n-type water/ alcohol-soluble conjugated polymers (n-WSCPs) were developed, which can act as electron transport layers (ETLs) to produce high-performance PSCs. Owing to the distinct electron-deficient nature of the backbones, these n-WSCPs exhibited different optoelectronic properties. The relationships between doping effects, charge-transporting capabilities, interfacial modifications, and structures of n-WSCPs were systematically investigated. When these n-WSCPs were used as ETLs, highperformance PSCs with the efficiencies of near 9% and over 10% were achieved in the combinations of poly [[2,6-4,8-di(5ethylhexylthienyl) [3,4-b]thiophenediyl]] (PTB7-Th)/ [6,6]-phenyl-C 71 -butyric acid methyl ester (PC 71 BM) and poly (2,5-thiophene-alt-5,5′-(5,10-bis(4-(2-octyldodecyl)thiophen-2yl)naphtho [1,2-c:5,6-c′]bis ([1,2,5]thiadiazole)) (PNTT)/PC 71 BM, respectively. The device of PNTT/PC 71 BM still exhibited a high PCE of 9.37% when the thickness of ETL was increased to 50 nm. Our results demonstrate the identical importance of energy level alignment and electron transporting in the design of n-WSCPs used for thickness-insensitive ETLs in PSCs for large area practical applications.

Conjugated polymers are emerging as promising organic photocatalysts for photocatalytic hydrogen evolution; however, they are suffering from poor water dispersabilities. Herein, this problem is addressed in an easy and green way with the assistance of a biomass-derived material. An amphipathic xylan derivative that can be selfassembled into nanomicelles was employed as carriers to encapsulate a series of conjugated polymers to form uniform composite micelles in water. By this way, the hydrophobic conjugated polymers and their blends were successfully dispersed into water and thus enabling efficient hydrogen evolution. Moreover, the energy level offsets of these conjugated polymers enable the formation of photoinduced charge transfer (PCT) process and fluorescence resonance energy transfer (FRET) process in their composite micelles. The photocatalytic experimental results showed that in these composite micelles, conjugated polymer blends with PCT characteristic delivered much higher photocatalytic hydrogen evolution rates over that of pristine polymer, while conjugated polymer blends with FRET characteristic delivered negligible improvement. Our results demonstrated effective strategies to improve the photocatalytic activity of conjugated polymers, which could also be applied to other photocatalytic materials and systems.

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As the power conversion efficiency (PCE) of polymer solar cells (PSCs) keeps increasing, developing high-performance large-area PSCs toward commercial application becomes a hot topic in this field. Here, we design and synthesize a non-fullerene acceptor TfIF-4Cl with a fused nonacyclic core via end-group chlorination. Compared to the fluorinated counterpart (TfIF-4F), the combination of the Cl atom in TfIF-4Cl not only leads to red-shifted absorption, but also improves the molecular packing ability. When TfIF-4Cl is blended with the polymer donor PM7 to fabricate the PSC, the device maintains high V OC (0.97 V, corresponding to a low energy loss of 0.60 eV) and presents enhanced J SC and high fill factor (78%), thus leading to an improved efficiency of 14% when compared with a PM7:TfIF-4F-based device. The high V OC but moderate photocurrent of PM7:TfIF-4Cl-based small-area device are beneficial to achieve large-area devices with high scalability according to the Joule’s law; thus, we manufacture 1.01 cm2 devices and achieve a remarkable PCE of 13.3%, which retain 95% in efficiency when the device area is scaled up from 0.04 to 1.01 cm2, and represent the best scalability when the device area is scaled up to 1 cm2 in the literature.

In this work, a star-shaped planar acceptor named FTr-3PDI was synthesized via ring-fusion between truxene core and three bay-linked perylene diimide (PDI) branches. Compared to the unfused non-planar acceptor Tr-3PDI, FTr-3PDI exhibits better structural rigidity and planarity, as well as more effective conjugation between truxene core and PDI branches. As a result, FTr-3PDI shows up-shifted energy levels, enhanced light absorption coefficient, increased electron mobility, and more favorable phase separation morphology in bulk-heterojunction (BHJ) blend films as compared to Tr-3PDI. Consequently, FTr-3PDI afforded higher power conversion efficiency (PCE) in BHJ solar cells when blended with a polymer donor PTB7-Th. This work demonstrates that ring-fusion is a promising molecular design strategy to combine the merits of truxene and PDI for non-fullerene acceptors used in organic solar cells.