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Many highly efficient all-polymer-based organic solar cells (OSCs) have been achieved owing to material design and device engineering. However, most of them were achieved by using halogenated solvents to process the active layers, being not beneficial to its nature of green energy technology. In this work, we compared chloroform- and toluene-processed PM6:PY-IT-based all-polymer devices with the same blend solution recipe, same film formation speed, and same postcast treatment. The film cast from toluene exhibited weaker crystallinity. For device performance, toluene enabled a better power conversion efficiency (PCE) of 15.51%, outperforming that of chloroform (15.00%), and it is the highest value for non-halogenated solvent-cast all-polymer-based OSCs to date. Toluene's morphology tuning effect was characterized to increase and balance the charge transport and then suppress the exciton recombination and improve the charge extraction, considered to be the reason for efficiency enhancement. Besides, the toluene-cast active layer-based devices showed slightly better photostability than the chloroform-driven ones. This work provided a new direction for building low-toxicity solvent-treated all-polymer OSCs with cutting-edge performance.

The non-fully conjugated polymer as a new class of acceptor materials has shown some advantages over its small molecular counterpart when used in photoactive layers for all-polymer solar cells (all-PSCs), despite a low power conversion efficiency (PCE) caused by its narrow absorption spectra. Herein, a novel non-fully conjugated polymer acceptor PFY-2TS with a low bandgap of ~1.40 eV was developed, via polymerizing a large π-fused small molecule acceptor (SMA) building block (namely YBO) with a non-conjugated thioalkyl linkage. Compared with its precursor YBO, PFY-2TS retains a similar low bandgap but a higher LUMO level. Moreover, compared with the structural analog of YBO-based fully conjugated polymer acceptor PFY-DTC, PFY-2TS shows a similar absorption spectrum and electron mobility, but significantly different molecular crystallinity and aggregation properties, which results in optimal blend morphology with a polymer donor PBDB-T and physical processes of the device in all-PSCs. As a result, PFY-2TS-based all-PSCs achieved a PCE of 12.31% with a small energy loss of 0.56 eV enabled by the reduced non-radiative energy loss (0.24 eV), which is better than that of 11.08% for the PFY-DTC-based ones. Our work clearly demonstrated that non-fully conjugated polymers as a new class of acceptor materials are very promising for the development of high-performance all-PSCs. [Figure not available: see fulltext.].

Jie Lin,1,2,* Yanlong Xue,1,2,* Wenyan Su,1,2,* Zan Zhang,1,2 Qiu Wei,1,2 Tianxia Huang1,2 1Department of Respiratory and Critical Care, The Fifth Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi, 530022, People’s Republic of China; 2Department of Respiratory and Critical Care, The First People’s Hospital of Nanning, Nanning, Guangxi, 530022, People’s Republic of China*These authors contributed equally to this workCorrespondence: Qiu Wei; Tianxia Huang, Department of Respiratory and Critical Care, The Fifth Affiliated Hospital of Guangxi Medical University, 89 Qixing Road, Nanning, Guangxi, 530022, People’s Republic of China, Tel +86 7712636163, Fax +86 7712617892, Email weiqiu2017@163.com; nntianxia620@sina.comPurpose: This study aimed to identify candidate gene markers that may facilitate chronic obstructive pulmonary disease (COPD) diagnosis and treatment.Methods: The GSE47460 and GSE151052 datasets were analyzed to identify differentially expressed mRNAs (DEmRs) between COPD patients and controls. DEmRs that were differentially expressed in the same direction in both datasets were analyzed for functional enrichment and for coexpression. Genes from the largest three modules were tested for their ability to diagnose COPD based on the area under the receiver operating characteristic curve (AUC). Genes with AUC > 0.7 in both datasets were used to perform regression based on the “least absolute shrinkage and selection operator” in order to identify feature genes. We also identified differentially expressed miRNAs (DEmiRs) between COPD patients and controls using the GSE38974 dataset, then constructed a regulatory network. We also examined associations between feature genes and immune cell infiltration in COPD, and we identified methylation markers of COPD using the GSE63704 dataset.Results: A total of 1350 genes differentially regulated in the same direction in the GSE47460 and GSE151052 datasets were found. The genes were significantly enriched in immune-related biological functions. Of 186 modules identified using MEGENA, the largest were C1_ 6, C1_ 3, and C1_ 2. Of the 22 candidate genes screened based on AUC, 11 feature genes emerged from analysis of a subset of GSE47460 data, which we validated using another subset of GSE47460 data as well as the independent GSE151052 dataset. Feature genes correlated significantly with infiltration by immune cells. The feature genes GPC4 and RS1 were predicted to be regulated by miR-374a-3p. We identified 117 candidate methylation markers of COPD, including PRRG4.Conclusion: The feature genes we identified may be potential diagnostic markers and therapeutic targets in COPD. These findings provide new leads for exploring disease mechanisms and targeted treatments.Keywords: chronic obstructive pulmonary disease, bioinformatics analysis, miRNAs, immune response, feature genes

Angiogenesis, a process highly regulated by pro-angiogenic and anti-angiogenic factors, is disrupted and dysregulated in cancer. Despite the increased clinical use of angiogenesis inhibitors in cancer therapy, most molecularly targeted drugs have been less effective than expected. Therefore, an in-depth exploration of the angiogenesis pathway is warranted. In this study, the expression of angiogenesis-related genes in various cancers was explored using The Cancer Genome Atlas datasets, whereupon it was found that most of them were protective genes in the patients with kidney renal clear cell carcinoma (KIRC). We divided the samples from the KIRC dataset into three clusters according to the mRNA expression levels of these genes, with the enrichment scores being in the order of Cluster 2 (upregulated expression) > Cluster 3 (normal expression) > Cluster 1 (downregulated expression). The survival curves plotted for the three clusters revealed that the patients in Cluster 2 had the highest overall survival rates. Via a sensitivity analysis of the drugs listed on the Genomics of Drug Sensitivity in Cancer database, we generated IC50 estimates for 12 commonly used molecularly targeted drugs for KIRC in the three clusters, which can provide a more personalized treatment plan for the patients according to angiogenesis-related gene expression. Subsequently, we investigated the correlation between the angiogenesis pathway and classical cancer-related genes as well as that between the angiogenesis score and immune cell infiltration. Finally, we used the least absolute shrinkage and selection operator (LASSO)–Cox regression analysis to construct a risk score model for predicting the survival of patients with KIRC. According to the areas under the receiver operating characteristic (ROC) curves, this new survival model based on the angiogenesis-related genes had high prognostic prediction value. Our results should provide new avenues for the clinical diagnosis and treatment of patients with KIRC.

Herein, we fabricated all-polymer solar cells (all-PSCs) based on a fluorinated wide-bandgap p-type conjugated polymer PM6 as the donor, and a narrow bandgap n-type conjugated polymer PZ1 as the acceptor. In addition to the complementary absorption and matching energy levels, the optimized blend films possess high cystallinity, predominantly face-on stacking, and a suitable phase separated morphology. With this active layer, the devices exhibited a high V oc of 0.96 V, a superior J sc of 17.1 mA cm -2 , a fine fill factor (FF) of 68.2%, and thus an excellent power conversion efficiency (PCE) of 11.2%, which is the highest value reported to date for single-junction all-PSCs. Furthermore, the devices showed good storage stability. After 80 d of storage in the N 2 -filled glovebox, the PCE still remained over 90% of the original value. Large-area devices (1.1 cm 2 ) also demonstrated an outstanding performance with a PCE of 9.2%, among the highest values for the reported large-area all-PSCs. These results indicate that the PM6:PZ1 blend is a promising candidate for scale-up production of large area high-performance all-PSCs.

Two non-fullerene electron acceptors (BT-SFIC and BT-FIC) bearing a dithienyl[1,2-b:4,5-b’]benzodithiophene core were designed and synthesized. Due to the strong electron-withdrawing ability of fluorine atoms, these two non-fullerene acceptors both show near-infrared absorption around 900 nm, with a narrow bandgap of 1.44 and 1.39 eV for BT-SFIC and BT-FIC, respectively. BT-SFIC and BT-FIC have complementary absorption and matched energy level with PTB7-Th. PSCs based on PTB7-Th donor and these two acceptors both show good charge dissociation and collection, small charge recombination and good active layer morphology. However, BT-FIC bearing much more fluorine have much higher electron mobility. And the PSCs based on PTB7-Th: BT-FIC gives a maximum PCE of 10.10% with a VOC of 0.73 eV, a JSC of 21.28 mA cm−2 and an FF of 65%, which is among in the high-performance polymer organic solar cells based on PTB7-Th.

Polymer solar cells (PSCs) based on narrow bandgap (NBG) photovoltaic materials have attracted significant attention due to their unique applications in semitransparent devices and organic tandem solar cells. In this work, we design and synthesize a new NBG polymer PBTT based on 2-(2-ethylhexyl)-thienyl substituted benzodithiophene (BDT-T) and n-octyl-3-fluorothieno[3,4-b]thiophene-2-carboxylate (TT) as donor material for the applications in non-fullerene PSCs. Compared with the widely used NBG polymer PTB7-Th, PBTT exhibited higher film extinction coefficient of 9.27 × 10 4 cm−1, higher-lying energy levels, more ordered molecule packing and higher hole mobility of 2.13 × 10 −3 cm2 V−1 s −1. The PSCs based on PBTT: IEICO obtained a power conversion efficiency (PCE) of 9.5% with a Voc of 0.86 V, a Jsc of 17.9 mA cm−2 and a FF of 61.3%, which is significantly enhanced over that (7.3%) of the corresponding devices with PTB7-Th as donor. The significantly improved PCE could be attributed to the higher charge mobility and the improved morphology of the PBTT: IEICO blend film. These results demonstrate that PBTT is a very promising NBG polymer donor material for the applications in non-fullerene PSCs.

Fluorine and alkylsilyl substitutions are two important strategies to reduce the energy levels and increase the absorption coefficient and hole mobility of photovoltaic materials simultaneously. Similar to fluorination, chlorination can also induce the intermolecular non-covalent interactions of Cl-H/S/Cl. Moreover, because chlorine (Cl) atoms contain empty 3d orbitals that can hold π-electrons from the conjugated skeleton, chlorination can decrease the molecular HOMO level more effectively than fluorination. Herein, we developed two wide bandgap polymer donors PBZ-Cl and PBZ-ClSi based on the Cl atom, and combined the Cl atom and alkylsilyl substituted thienyl benzodithiophene (BDTT-Cl and BDTT-ClSi) as donor units, respectively. From the control polymer PBZ to PBZ-Cl and then to PBZ-ClSi, the polymers show a gradually reduced HOMO level, increased absorption coefficient and improved charge mobility. As a result, the PBZ-ClSi:IT-4F-based PSCs fabricated by the nonhalogen solvents achieved a high power conversion efficiency (PCE) of 12.8% with a high open-circuit voltage (V oc ) of 0.93 V, short-circuit current density (J sc ) of 19.2 mA cm -2 , fill factor (FF) of 71.5% and a low energy loss of 0.57 eV, while the PSCs based on PBZ and PBZ-Cl only obtained lower PCEs of 6.4% and 9.7%, respectively. The PCE of 12.8% is one of the highest values recorded for nonhalogen solvent-processed PSCs to date. The results indicate that the combination of Cl atoms and alkylsilyl substituents is a simple and effective method for designing high efficiency polymer photovoltaic materials.

How to simultaneously achieve both high open‐circuit voltage (V oc) and high short‐circuit current density (J sc) is a big challenge for realising high power conversion efficiency (PCE) in all‐small‐molecule organic solar cells (all‐SM OSCs). Herein, a novel small molecule (SM)‐donor, namely FYSM−SiCl, with trialkylsilyl and chlorine substitutions was designed and synthesized. Compared to the original SM‐donor FYSM−H, FYSM−Si with trialkylsilyl substitution showed a decreased crystallinity and lower highest occupied molecular orbital (HOMO) level, while FYSM−SiCl had an improved crystallinity, more ordered packing arrangement, significantly lower HOMO level, and predominant “face‐on” orientation. Matched with a SM‐acceptor Y6, the FYSM−SiCl‐based all‐SM OSCs exhibited both high V oc of 0.85 V and high J sc of 23.7 mA cm−2, which is rare for all‐SM OSCs and could be attributed to the low HOMO level of FYSM−SiCl donor and the delicate balance between high crystallinity and suitable blend morphology. As a result, FYSM−SiCl achieved a high PCE of 13.4 % in all‐SM OSCs, which was much higher than those of the FYSM−H‐ (10.9 %) and FYSM−Si‐based devices (12.2 %). This work demonstrated a promising method for the design of efficient SM‐donors by a side‐chain engineering strategy via the introduction of trialkylsilyl and chlorine substitutions., Superb substitution: A small molecule donor FYSM−SiCl with trialkylsilyl and chlorine substitutions is developed. Compared to its unsubstituted analogue FYSM−H, FYSM−SiCl has a deep‐shifted highest occupied molecular orbital level, improved crystallinity and hole‐mobility, and a predominantly “face‐on” orientation. FYSM−SiCl‐based all‐small‐molecule solar cells achieve a much higher power conversion efficiency of 13.4 % compared to the FYSM−H‐based ones (10.9 %).

The ternary polymerization strategy of incorporating different donor and acceptor units forming terpolymers as photovoltaic materials has been proven advantageous in improving power conversion efficiencies (PCEs) of polymer solar cells (PSCs). Herein, a series of low band gap nonconjugated terpolymer acceptors based on two different fused-ring electron-deficient building blocks (IDIC16 and ITIC) with adjustable photoelectric properties were developed. As the third component, ITIC building blocks with a larger pi-conjugation structure, shorter solubilizing side chains, and red-shifted absorption spectrum were incorporated into an IDIC16-based nonconjugated copolymer acceptor PF1-TS4, which built up the terpolymers with two conjugated building blocks linked by flexible thioalkyl chain-thiophene segments. With the increasing ITIC content, terpolymers show gradually broadened absorption spectra and slightly down-shifted lowest unoccupied molecular orbital levels. The active layer based on terpolymer PF1-TS4-60 with a 60% ITIC unit presents more balanced hole and electron mobilities, higher photoluminescence quenching efficiency, and improved morphology compared to those based on PF1-TS4. In all-polymer solar cells (all-PSCs), PF1-TS4-60, matched with a wide band gap polymer donor PM6, achieved a similar open-circuit voltage (V-oc) of 0.99 V, a dramatically increased short-circuit current density (J(sc)) of 15.30 mA cm(-2), and fill factor (FF) of 61.4% compared to PF1-TS4 = 0.99 V, J(sc) = 11.21 mA cm(-2), and FF = 55.6%). As a result, the PF1-TS4-60-based all-PSCs achieved a PCE of 9.31%, which is similar to 50% higher than the PF1-TS4-based ones (6.17%). The results demonstrate a promising approach to develop high-performance nonconjugated terpolymer acceptors for efficient all-PSCs by means of ternary polymerization using two different A-D-A-structured fused-ring electron-deficient building blocks.

Obtaining both high open-circuit voltage (V-oc) and short-circuit current density (J(sc)) has been a major challenge for efficient all-polymer solar cells (all-PSCs). Herein, we developed a polymer acceptor PF5-Y5 with excellent optical absorption capability (onset extending to similar to 880 nm and maximum absorption coefficient exceeding 105 cm(-1) in a film), high electron mobility (3.18 x 10(3) cm(2) V-1 s(-1)) and high LUMO level (-3.84 eV) to address such a challenge. As a result, the PBDB-T:PF5-Y5-based all-PSCs achieved a high power conversion efficiency of up to 14.45% with both a high Voc (0.946 V) and a high Jsc (20.65 mA cm(-2)), due to the high and broad absorption coverage, small energy loss (0.57 eV) and efficient charge separation and transport in the device, which are among the best values in the all-PSC field. In addition, the all-PSC shows a similar to 15% improvement in PCE compared to its counterpart small molecule acceptor (Y5)-based device. Our results suggest that PF5-Y5 is a very promising polymer acceptor candidate for applications in efficient all-PSCs. Funding Agencies|Swedish Research CouncilSwedish Research Council [2015-04853, 2016-06146, 2019-04683]; Swedish Research Council FormasSwedish Research CouncilSwedish Research Council Formas; Wallenberg Foundation [2017.0186, 2016.0059]; Innovation fund Denmark (INKA project); Sino-Danish Centre for Education and Research (SDC); King Abdullah University of Science and Technology (KAUST)King Abdullah University of Science & Technology [OSR-2018-CARF/CCF-3079]; Office of Sponsored Research (OSR) [OSR-2018-CARF/CCF-3079]; Jinan University Postdoctoral Science Foundation; China Postdoctoral Science FoundationChina Postdoctoral Science Foundation [2020M673054]; National Natural Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [22005121, 61805009]

A non‐conjugated polymer acceptor PF1‐TS4 was firstly synthesized by embedding a thioalkyl segment in the mainchain, which shows excellent photophysical properties on par with a fully conjugated polymer, with a low optical band gap of 1.58 eV and a high absorption coefficient >105 cm−1, a high LUMO level of −3.89 eV, and suitable crystallinity. Matched with the polymer donor PM6, the PF1‐TS4‐based all‐PSC achieved a power conversion efficiency (PCE) of 8.63 %, which is ≈45 % higher than that of a device based on the small molecule acceptor counterpart IDIC16. Moreover, the PF1‐TS4‐based all‐PSC has good thermal stability with ≈70 % of its initial PCE retained after being stored at 85 °C for 180 h, while the IDIC16‐based device only retained ≈50 % of its initial PCE when stored at 85 °C for only 18 h. Our work provides a new strategy to develop efficient polymer acceptor materials by linkage of conjugated units with non‐conjugated thioalkyl segments., An efficient non‐conjugated polymer acceptor PF1‐TS4 was developed by embedding thioalkyl linkages in the mainchain of a conjugated polymer. The resulting all‐polymer solar cells achieved a promising device efficiency of 8.63 % with excellent thermal stability at 85 °C for 180 hours.

Regulating molecular structure to optimize the active layer morphology is of considerable significance for improving the power conversion efficiencies (PCEs) in organic solar cells (OSCs). Herein, we demonstrated a simple ternary copolymerization approach to develop a terpolymer donor PM6-Tz20 by incorporating the 5,5'-dithienyl-2,2'-bithiazole (DTBTz, 20 mol%) unit into the backbone of PM6 (PM6-Tz00). This method can effectively tailor the molecular orientation and aggregation of the polymer, and then optimize the active layer morphology and the corresponding physical processes of devices, ultimately boosting FF and then PCE. Hence, the PM6-Tz20: Y6-based OSCs achieved a PCE of up to 17.1% with a significantly enhanced FF of 0.77. Using Ag (220 nm) instead of Al (100 nm) as cathode, the champion PCE was further improved to 17.6%. This work provides a simple and effective molecular design strategy to optimize the active layer morphology of OSCs for improving photovoltaic performance.

The limited light absorption capacity for most polymer acceptors hinders the improvement of the power conversion efficiency (PCE) of all-polymer solar cells (all-PSCs). Herein, by simultaneously increasing the conjugation of the acceptor unit and enhancing the electron-donating ability of the donor unit, a novel narrow-bandgap polymer acceptor PF3-DTCO based on an A–D–A-structured acceptor unit ITIC16 and a carbon–oxygen (C–O)-bridged donor unit DTCO is developed. The extended conjugation of the acceptor units from IDIC16 to ITIC16 results in a red-shifted absorption spectrum and improved absorption coefficient without significant reduction of the lowest unoccupied molecular orbital energy level. Moreover, in addition to further broadening the absorption spectrum by the enhanced intramolecular charge transfer effect, the introduction of C–O bridges into the donor unit improves the absorption coefficient and electron mobility, as well as optimizes the morphology and molecular order of active layers. As a result, the PF3-DTCO achieves a higher PCE of 10.13% with a higher short-circuit current density (Jsc) of 15.75 mA cm−2 in all-PSCs compared with its original polymer acceptor PF2-DTC (PCE = 8.95% and Jsc = 13.82 mA cm−2). Herein, a promising method is provided to construct high-performance polymer acceptors with excellent optical absorption for efficient all-PSCs.

Great attention has been paid to developing low bandgap non-fullerene acceptors (NFAs) for matching wide bandgap donor polymers to increase the photocurrent and therefore the power conversion efficiencies (PCEs) of NFA organic solar cells, while pyrene-core based acceptor–donor–acceptor (A–D–A) NFAs have been mainly reported via the 2,9-position connection due to their bisthieno[30,20-b']thienyl[a,h]pyrene fused via a five-membered ring bridge at the ortho-position of pyrene as the representative one named FPIC5, which has prohibited further narrowing their energy gap. Herein, an acceptor FPIC6 was exploited by creating the 1,8-position connection through fusing as bisthieno[30,20-b0]thienyl[f-g,m-n]pyrene linked at the bay-position via a six-membered bridge, with enhanced push–pull characteristics within such A–D–A structure. As a structural isomer of FPIC5, FPIC6 exhibited a much lower bandgap of 1.42 eV (1.63 eV for FPIC5). Therefore, the photocurrent and PCE of PTB7-Th:FPIC6 cells were improved to 21.50 mA cm2 and 11.55%, respectively, due to the balanced mobilities, better photoluminescence quenching efficiency and optimized morphology, which are both40% better than those of PTB7-Th:FPIC5 cells. Our results clearly proved that a pyrene fused core with 1,8-position connection with electron-withdrawing end groups instead of 2,9-position connection is an efficient molecular design strategy to narrow the optical bandgap and improve the photovoltaic performance of NFA based OSCs.

Herein, a novel small molecule donor is first developed, FSM6, which is a cognate molecule to BTR possessing similar molecular structure with comparable optical absorption but different crystallinity. The efficient fullerene-type ternary small molecular solar cells (SMSCs) based on an alloy donor of BTR and FSM6 in a thick film of 250 nm reveal the improved hierarchical phase separation morphology and molecular structural order of ternary active layers with improved crystallinity of the key donor component BTR. Furthermore, FSM6 as the key third component also plays a role of charge transfer accelerator in ternary SMSCs. As a result, the optimal ternary SMSCs based on BTR:FSM6:PC71BM achieve a high power conversion efficiency (PCE) up to 10.21% with the synergistically improved open-circuit voltage of 0.950 V, short-circuit current density of 13.85 mA cm−2, and fill factor of 77.6%, in comparison with either the binary SMSCs of BTR:PC71BM (PCE = 9.37%) or FSM6:PC71BM (PCE = 8.00%). This work provides a promising methodology to optimize device morphology for high-performance ternary SMSCs by combining two cognate small molecules with similar absorption spectra but different crystallinity as an alloy donor.

We developed three narrow band-gap polymer acceptors PF2-DTC, PF2-DTSi, and PF2-DTGe with different bridging atoms (i.e., C, Si, and Ge). Studies found that such different bridging atoms significantly affect the crystallinity, extinction coefficient, electron mobility of the polymer acceptors, and the morphology and mechanical robustness of related active layers. In all-polymer solar cells (all-PSCs), these polymer acceptors achieved high power conversion efficiencies (PCEs) over 8.0%, while PF2-DTSi obtained the highest PCE of 10.77% due to its improved exciton dissociation, charge transport, and optimized morphology. Moreover, the PF2-DTSi-based active layer showed excellent mechanical robustness with a high toughness value of 9.3 MJ m−3 and a large elongation at a break of 8.6%, which is a great advantage for the practical applications of flexible devices. As a result, the PF2-DTSi-based flexible all-PSC retained >90% of its initial PCE (6.37%) after bending and relaxing 1,200 times at a bending radius of ∼4 mm.

Objective. Over decades, numerous inconsistent studies are reported on the relationship between soluble α-Klotho and renal function in patients with chronic kidney disease (CKD). This study aims to perform a meta-analysis to figure out the correlations between soluble α-Klotho and renal function in patients with CKD. Materials and Methods. We searched medical and scientific literature databases, PubMed and EMBASE (from the inception to October 2017), for publications that reported studies on associations between soluble α-Klotho and renal function in patients with CKD. Only publications in English were extracted. Summary correlation coefficient (r) values were extracted from each study, and 95% confidence intervals (CIs) were calculated. Publication bias was tested, and sensitivity and subgroup analyses were performed to investigate potential heterogeneity. Results. Of 611 studies, 9 publications with 1457 patients were included into the analysis. The following data were extracted from the literature: first author, year of publication, research region, research index, sample size, average age and Pearson or Spearman correlation coefficient, study design, the αKlotho/FGF23 assays utilized, full length, or the C-terminal fragment of FGF23. The pooled r between α-Klotho and estimated glomerular filtration rate (eGFR), FGF-23 were 0.35 (95%CI, 0.23~0.46, and Pα-Klotho and eGFR stratified by research region, mean age, and eGFR, but heterogeneity exists in analyses of α-Klotho and FGF-23 stratified by research region. There was no significant correlation between a-klotho and Ca and PTH and PHOS. There was no evidence of publication bias with Egger’s test (p=0.360) or with Begg’s test (p=0.902) and the distribution of funnel plots was symmetrical in all of our analysis. Conclusions. There exists a significant positive correlation between soluble α-Klotho and eGFR in patients with CKD. Also, a significant negative correlation between α-Klotho and FGF23 levels is proven. This raises hope to employ αKlotho and FGF23 as early biomarkers of CKD. However, further large prospective follow-up researches are needed to validate this hypothesis and to explore whether maintaining or elevating the Klotho level could improve renal function and complications in CKD patients.

A new narrow-bandgap copolymer PBFTT, based on 4,8-bis(5-(2-ethylhexyl)-4-fluorothiophen-2-yl)benzo[1,2-b:4,5-b']dithiophene (BDT-2F) as donor unit and octyl-3-fluorothieno[3,4-b]thiophene-2-carboxylate (TT) as acceptor unit, was synthesized as donor material for non-fullerene (NF) polymer solar cells (PSCs) application. Compared to the analogue polymer PTB7-Th, PBFTT with two fluorine atoms in the conjugated side chains of BDT possesses a deeper HOMO energy level of −5.47 eV and a slightly enhanced hole mobility of 3.13 × 10−3 cm2 V-1 s-1 versus (vs.) a HOMO energy level of −5.30 eV and a hole mobility of 1.11 × 10−3 cm2 V-1 s-1 for PTB7-Th. Hence, the corresponding PSCs based on PBFTT:ITIC exhibited an optimal PCE of 9.1% with a Voc of 0.94 V, a Jsc of 16.0 mA cm−2, and a FF of 60.5% compared to a PCE of 6.8% with a Voc of 0.81 V, a Jsc of 14.2 mA cm−2 and a FF of 59.1% for PTB7-Th:ITIC-based PSCs. Notably, this PCE is among the highest values for the NF-PSCs based on narrow-bandgap polymer without extra treatments. These results indicate that PBFTT is a promising narrow-bandgap polymer donor material for NF-PSCs application.

In the past few years, fluorine atom has been widely introduced into organic semiconductor (OS) materials to improve the photovoltaic performance of polymer solar cells (PSCs). In contrast, chlorine atom is rarely concerned, although it is also a halogen element and is more easily introduced into OS materials. Herein, we designed and synthesized a new D-A-type two-dimension (2D)-conjugated polymer, PM7, containing a chlorinated-thienyl benzodithiophene (BDT-2Cl) donor unit and a benzodithiophene-4,8-dione acceptor unit. Compared to the control polymer PBDB-T without chlorine substitution, PM7 shows lower HOMO energy level, higher absorption coefficient, enhanced crystallinity and higher carrier mobility. Moreover, the toluene-processed PSCs based on PM7 as donor and small molecule n-OS IT-4F as acceptor achieved a high power conversion efficiency (PCE) of 13.1% with high open-circuit voltage (Voc) of 0.88 V, short-circuit current density (Jsc) of 20.9 mA cm−2 and fill factor (FF) of 71.1%, while the PBDB-T:IT-4F-based PSC only exhibited a low PCE of 5.8% with low Voc of 0.67 V, Jsc of 15.0 mA cm−2 and FF of 57.6%. The PCE of 13.1% is among the highest values reported for the PSCs to date. These results indicate that the chlorine substitution is a simple and effective strategy to design high-performance conjugated polymer photovoltaic materials.

A high performance polymer solar cells (PSCs) based on polymer donor PM6 containing fluorinated thienyl benzodithiophene unit and n -type organic semiconductor acceptor IT-4F containing fluorinated end-groups were developed. In addition to complementary absorption spectra ( 300–830 nm) with IT-4F, the PM6 also has a deep HOMO (the highest occupied molecular) level (−5.50 eV), which will lower the open-circuit voltage ( V oc) sacrifice and reduce the E loss of the IT-4F-based PSCs. Moreover, the strong crystallinity of PM6 is beneficial to form favorable blend morphology and hence to suppress recombination. As a result, in comparison with the PSCs based on a non-fluorinated D/A pair of PBDB-T:ITIC with a medium PCE of 11.2%, the PM6:IT-4F-based PSCs yielded an impressive PCE of 13.5% due to the synergistic effect of fluorination on both donor and acceptor, which is among the highest values recorded in the literatures for PSCs to date. Furthermore, a PCE of 12.2% was remained with the active layer thickness of up to 285 nm and a high PCE of 11.4% was also obtained with a large device area of 1 cm2. In addition, the devices also showed good storage, thermal and illumination stabilities with respect to the efficiency. These results indicate that fluorination is an effective strategy to improve the photovoltaic performance of materials, as well as the both fluorinated donor and acceptor pair-PM6:IT-4F is an ideal candidate for the large scale roll-to-roll production of efficient PSCs in the future.

To achieve efficient polymer solar cells (PSCs), it is important to increase the optical absorption coefficient and charge mobility of photovoltaic materials for obtaining a high short-circuit current density (Jsc) and fill factor (FF) in the devices without sacrificing the open-circuit voltage (Voc). Herein, we designed and synthesized two novel narrow bandgap n-type organic semiconductor (n-OS) acceptors named POIT-M and MOIT-M by modifying the side-chains of IT-M from para-hexylphenyl to para-hexyloxylphenyl and then to meta-hexyloxylphenyl. Due to the synergistic effects of introducing oxygen atoms and varying substitution positions on the phenyl side-chains, MOIT-M shows a significantly improved absorption coefficient, stronger intermolecular π–π stacking interaction, increased crystallinity and higher electron mobility in comparison with IT-M and POIT-M, which helps to gain higher Jsc and FF in PSCs. These special features combined with the complementary absorption of the MOIT-M acceptor and wide bandgap polymer PTZ1 donor resulted in a high power conversion efficiency (PCE) of 11.6% with a Voc of 0.96 V, a Jsc of 17.5 mA cm−2 and a FF of 68.8% for the PSCs processed with simple thermal annealing at 120 °C for 10 min, which is one of the highest PCEs reported for additive-free PSCs and significantly higher than those of the PSCs based on PTZ1:IT-M (9.1%) or PTZ1:POIT-M (9.7%). Our results indicate that side-chain engineering is an effective way to further improve the photovoltaic performance of n-OS acceptors in PSCs.

All-polymer solar cells (all-PSCs) based on an n-type polymer as an acceptor material and a p-type polymer as a donor material have attracted great attention due to their excellent device stability. However, a systematic study of the thermal stability of all-PSCs has not been reported to date. Herein, we developed a highly efficient and thermally stable all-PSCs based on a fluorinated wide-bandgap polymer donor (PFBZ) and a narrow-bandgap polymer acceptor (N2200). The PFBZ:N2200 pair exhibited complementary absorption spectra, matched energy levels, and good blend morphology. As a result, PFBZ:N2200-based devices after thermal annealing at 150 °C for 15 min achieved a high power conversion efficiency (PCE) of 8.1% with a high open-circuit voltage of 0.90 V, a short-circuit current density of 13.5 mA cm−2, a fill factor of 67.0%, as well as a low energy loss of 0.56 eV. The efficiency of 8.1% is one of the highest values reported for the additive-free all-PSCs. When the thermal annealing time was extended to 180 min or the temperature was increased to 250 °C, the all-PSCs retained a high PCE of over 7%. These results indicate that the PFBZ:N2200-based all-PSCs with high efficiency and excellent thermal stability are promising candidates for the practical applications of OSCs.

In this work, we developed high efficiency nonfullerene PSCs based on a wide bandgap polymer donor PBPD-Th with a structure of meta-alkoxyphenyl benzodithiophene-alt-thienyl benzodithiophene-4,8-dione and a low bandgap small molecule acceptor ITIC. The PBPD-Th shows a strong absorption in the short wavelength of 300–650 nm with a bandgap of 1.91 eV, which is complementary with that of ITIC (1.55 eV). Moreover, PBPD-Th possesses a deep HOMO level of −5.42 eV, which is beneficial to obtain high open-circuit voltage (Voc) in PSCs. As a result, the optimal PSCs based on PBPD-Th: ITIC showed a power conversion efficiency (PCE) of 10.8% with a Voc of up to 1.01 V, a high short-circuit current density (Jsc) of 18.3 mA cm−2 and a fill factor (FF) of 59%, under the illumination of AM 1.5 G, 100 mW cm−2. Notably, the energy loss (Eloss) of the optimal PSCs is 0.54 eV, which is smaller than the empirically low threshold of 0.6 eV. The PCE of 10.8% is one of the highest values reported in the literatures for the PSCs with Voc over 1.0 V.

In this work, we fabricated high efficient ternary PSCs based on two compatible non-fullerene acceptors (IDIC and ITIC) with similar chemical structures and one new D-A-type polymer (PSTZ) donor. By inserting ITIC into the binary PSTZ:IDIC system, the active layer show smooth and gradient energy levels, improved crystallinity and optimized morphologies, which results in efficient exciton separation, charge transport and collection. As a result, the optimal ternary PSCs based on PSTZ:ITIC:IDIC (1:0.1:0.9) exhibited a higher PCE of 11.1% with a Voc of 0.953 V, Jsc of 17.4 mA cm−2 and FF of 66.9% in comparison with those of binary PSC systems based on PSTZ:IDIC (PCE of 8.06%) or PSTZ:ITIC (PCE of 8.13%). These results indicate that combining two compatible nonfullerene acceptors with similar structures to fabricate ternary PSCs should be a promising strategy to enhance the photovoltaic performance of the PSCs.

In this work, a new D–A copolymer based on m-alkoxyphenyl substituted benzodithiophene (BDT-m-OP) as donor unit and benzo[1,2-c:4,5-c′]dithiophene-4,8-dione (BDD) as acceptor unit was designed and synthesized, in which selenophene unit as π-conjugated spacer was incorporated into the polymer backbone to broaden the absorption spectrum, enhance the charge transport properties, and even improve the photovoltaic properties. Compared with PBPD-Th with thiophene as π-conjugated spacer, PBPD-Se exhibits an evidently extended absorption spectrum and an enhanced hole mobility with a slightly raised HOMO energy level. The PBPD-Se:PC71BM-based PSCs exhibits a significantly improved PCE of 9.8% with an enhanced Jsc of 14.9 mA cm–2 and a slightly lower Voc of 0.90 V in comparison with a PCE of 8.4% with a Voc of 0.95 V and a Jsc of 12.4 mA cm–2 for PBPD-Th:PC71BM-based devices. These results indicate that the rational selection of π-conjugated spacer in the D–A copolymer backbone is very essential to achieve high eff...