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Aim: This meta‐analysis systematically reviewed and identified the effects of WeChat‐based continuous care (WCC) interventions on various outcomes in cancer patients. Design: Systematic review and meta‐analysis. Methods: In this study, outcome measures included somatic function, anxiety, depression, social function, and cognitive function. The standardized mean differences and 95% CIs of pooled effect sizes were calculated using fixed‐ and random‐effects models. NFail‐safe and Begg's tests were performed to evaluate publication bias, and sensitivity analysis was performed to evaluate the robustness of the meta‐analysis results. Results: The meta‐analysis included 18 RCTs of moderate quality. WCC interventions significantly improved somatic function, depression, anxiety, social function, and cognitive function in cancer patients. There was no significant publication bias, and the sensitivity analysis indicated robust results. Patient or Public Contribution: WCC interventions improved depression, anxiety, social function, and cognitive function in cancer patients. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Constructing monolithic tandem solar cells (TSCs) is an effective method to break the Shockley–Queisser (S–Q) radiative efficiency limit for single‐junction solar cells. Employing the wide bandgap perovskite materials and low bandgap organic materials as absorber layers for front and rear subcells, respectively, to construct perovskite/organic TSCs can complementarily absorb sunlight in ultraviolet‐visible (UV‐Vis) range by front perovskite and near‐infrared (NIR) range by rear organic molecules, thus reducing the thermalization energy losses. Besides the subcells, the interconnection layer (ICL), which physically and electrically connects the front and rear subcells, is also an important tunnel junction to recombine charges. In this review, we summarize the optimization strategies of wide bandgap perovskites for front subcell, narrow bandgap organic material for rear subcell, and the ICLs employed in monolithic perovskite/organic TSCs. [ABSTRACT FROM AUTHOR]

All‐inorganic CsPbI2Br perovskite has attracted great attention due to the stable crystal structure and moisture resistance, and its 1.91 eV bandgap is close to the optimal bandgap of indoor artificial light sources, making it be the best candidate for the indoor photovoltaics (IPVs) to power a wide range of internet of things related electronic devices. Herein, we report on the preparation of CsPbI2Br with α‐phase and the improvement of its phase stability by adding lead acetate in the CsPbI2Br precursor. A series of dopant‐free conjugated polymers (P3HT, PBDB‐T, and PM6) with different highest occupied molecular orbital energy levels are introduced as hole transport layers for building IPV devices. The PM6 based devices having better energy alignment with perovskite demonstrate best indoor photovoltaic performance, giving a remarkable open‐circuit voltage of 1.15 V and high fill factor of 81.86% under 1000 lux (330 µW cm−2) light‐emitting diode illumination, and finally realizing a decent power conversion efficiency of 33.68%. Our findings suggest that collaboratively optimize the CsPbI2Br layer and hole transport layer is an effective approach to realize high performance IPVs. [ABSTRACT FROM AUTHOR]

Semitransparent organic solar cells (ST‐OSCs) with vivid colors offer attractive prospects in aesthetical power‐generating windows. Unfortunately, they still suffer from certain limitations since the common approach for generating different colors is to adopt various photoactive layers, which complicates production processes and results in process‐induced performance deviations. Additionally, efficient ST‐OSCs with simultaneously improved average visible transmittance (AVT) and color rendering index (CRI) remain still challenging due to the trade‐off between photoelectric conversion efficiency (PCE) and AVT besides the interdependent/interactive relations of AVT and CRI. Herein, Ag/MoO3/Ag microcavity structure is introduced to delicately tune the absorption spectra of PM6:Y6 active material. The Ag/MoO3/Ag microcavity endows freely tunable colors to devices and meanwhile functions as a hole‐collecting layer. Under the guidance of optical simulation, the rationally designed ST‐OSCs with Ag/MoO3/Ag microcavity and Hf(ACB1)4 electron collection layer display good eye comfort colors (purple, sky blue, cyan, green, and magenta) independently of the inherent color of PM6:Y6 active material, and show a close to 12% PCE with an AVT of 23.69% and a CRI of 92.5 for cyan devices. This work provides a practical way for achieving efficient ST‐OSCs with simultaneously improved AVT and CRI, and using them in building‐integrated photovoltaics as multicolored photovoltaic glass windows. [ABSTRACT FROM AUTHOR]

Quinone‐based aqueous redox flow batteries (RFBs) have drawn much attention due to their high safety, two‐electron involvement, rapid reaction kinetics, property tunability, and potentially low cost. RFBs operating in neutral solution feature a wide electrochemical window of around 2.5 V, which provides much more space for the design of redox‐active materials (RAMs) to realize a high voltage. However, it is still challenging to achieve low potential in the neutral condition for quinone‐based RAMs, owing to inherently pH‐dependent behaviors and deep LUMO (the lowest unoccupied molecular orbital) energy level. Herein, we report three low‐potential quinone‐based RAMs (1,4‐BDPAQCl2, 1,5‐BDPAQCl2, and 1,8‐BDPAQCl2) by bis‐dimethylamino substitution. The half‐wave potential of the quinones in 0.5 M KCl is approximately −0.55 to −0.57 V versus a normal hydrogen electrode. The low potential is ascribed to the introduced functional groups with two effects. First, the intramolecular hydrogen bonds formed between C=O and H−N can weaken the association between protons and dianion Q2−, resulting in a favorable distribution of products. Second, the functional groups can effectively increase the LUMO over 0.22 eV, compared with anthraquinone. Paired with Fe(glycine)2Cl2, the theoretical open‐circuit voltage of full RFBs is achieved at 1.27–1.29 V. We test full batteries using these quinones as negative RAMs at a lower concentration (0.1 M). The results show that 1,8‐BDPAQCl2 displays stability during 300 charge‐discharge cycles. In contrast, the other two quinones exhibit poor cycling stability due to side reactions. We further execute a higher concentration (0.4 M) for 1,8‐BDPAQCl2. The cycling stability of the quinone−iron RFBs is outstanding, with 0.048 % capacity decay per cycle and 0.88 % capacity decay per day. Our finding offers a feasible strategy to design low‐potential quinone molecules for the neutral RFBs. [ABSTRACT FROM AUTHOR]

A better charge balance is realized for blue quantum dot light‐emitting diodes (QLEDs) through doping the charge transport layer (CTL) to improve hole injection and suppress redundant electrons. High performance blue QLEDs were achieved by fine‐tuning the charge balance within the emitting layer. [ABSTRACT FROM AUTHOR]

Abstract: Ternary polymer solar cells (PSCs) based on multiple materials with level matching and complementary absorptions are regarded as an efficient way to overcome the light‐harvesting restriction to surpass high‐performance binary PSCs. This study introduces the third component, nonfullerene acceptor IEICO, into binary PSC‐based PBDTBDD:PC71BM to fabricate ternary PSC with one donor and two acceptors. By carefully tuning the third component ratio and cathode engineering, the resulting ternary PSC shows a power conversion efficiency of 10.51%, greatly improved in comparison with binary PSCs‐based PBDTBDD:PC71BM (7.86%) and PBDTBDD:IEICO (5.19%). In addition to extended light absorption, the third component IEICO could accelerate charge‐carrier transfer, decrease charge recombination, and increase electron collection, resulting from cascade energy levels, and ameliorate the device morphology to increase the contact area of the active layer and cathode buffer layer. This work demonstrates that ternary PSC incorporated with IEICO is a promising structure for producing high performance PSCs. [ABSTRACT FROM AUTHOR]

High efficiency polymer solar cells using solution processed s‐ReOx as the anode buffer layer are demonstrated. The s‐ReOx layer can effectively change the light distribution within the photoactive layer and enhance its absorption. The solution‐processable s‐ReOx is a promising anode buffer layer material for high performance PSCs [ABSTRACT FROM AUTHOR]

ABSTRACT Novel bromine-functionalized photocrosslinkable low-bandgap copolymers, PBDTTT-Br25 and PBDTTT-Br50, are synthesized via Stille cross-coupling polymerization for the purpose of stabilizing the film morphology in polymer solar cells (PSCs). Photocrosslinking of PBDTTT-Br25 and PBDTTT-Br50 copolymers dramatically improves the solvent resistance of the active layer without disrupting the molecular ordering and charge transport, which is confirmed by the insolubility of the films washed by organic solvents and by their thermal behavior. As a result, the formation of large aggregations of fullerene is suppressed in polymer:fullerene blend films even after prolonged thermal annealing, and the stability of the device is enhanced when compared with cells based on noncrosslinkable PBDTTT. The power conversion efficiency of the PSCs based on PBDTTT-Br25 and PBDTTT-Br50 reaches 5.17% and 4.48%, respectively, which is improved obviously in comparison with that (4.26%) of the PSCs based on the control polymer PBDTTT. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3123-3131 [ABSTRACT FROM AUTHOR]

We report polymer solar cells (PSCs) based on poly(3-hexylthiophene (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) using water-soluble nickel acetate (Ni(CH3COO)2, NiAc) instead of acidic poly(3,4-ethylenedioxythiophene) : poly(styrenesulfonate) (PEDOT : PSS) as hole collection layer (HCL) between the indium tin oxide (ITO) electrode and photoactive layer. The NiAc layer can effectively decrease Rs and increase Rp and shows effective hole collection property. Under the illumination of AM1.5G, 100 mW/cm2, the short-circuit current density ( Jsc) of the NiAc based device (ITO/NiAc/P3HT : PCBM/Ca/Al) reach 11.36 mA/cm2, which is increased by 11% in comparison with that (10.19 mA/cm2) of PEDOT : PSS based device (ITO/PEDOT : PSS/P3HT : PCBM/Ca/Al). The power conversion efficiency of the NiAc based devices reach 3.76%, which is comparable to that (3.77%) of the device with PEDOT : PSS HCL under the same experimental conditions. Moreover, NiAc based PSCs show superior long-term stability than PEDOT : PSS based PSCs. Our work gives a new option for HCL selection in designing more stable PSCs. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

The balance of hole–electron injection is always a vital factor for the luminance, efficiency and working lifetime of quantum‐dot light‐emitting diodes (QLEDs), especially blue QLEDs. However, currently most approaches proposed to solve this issue involve tedious optimization of device architecture or material composition. Here, high‐performance blue QLEDs are reported based on CdZnS/ZnS quantum‐dot (QDs) by utilizing ZnO nanoparticles (NPs) and Al:Al2O3 as electron‐transporting layer (ETL) and cathode materials, respectively. The effect of post‐annealing temperature on the trap state density in ZnO NPs and the related mechanisms are investigated through optical and photoelectron spectroscopies. The method of controlling ZnO NPs annealing temperature leads to controllable electron‐mobility of ETL, which ultimately optimizes the balance of charge injection. Together with partially oxidized Al cathode (Al:Al2O3), high‐performance blue QLEDs are fabricated with luminance and external quantum efficiency (EQE) up to 27 753 cd m−2 and 8.92%. As far as is known, the peak luminance achieved is the record of deep blue QLEDs. This simple method for regulating charge injection balance via annealing temperature requires no modification of device architecture, making it applicable for a variety of QLEDs structures. High‐performance blue QLEDs are fabricated based on a ZnO nanoparticle (NP) electron‐transporting layer and a Al:Al2O3 cathode. The electron mobility in ZnO NP films can be regulated for better electron–hole balance by controlling the annealing temperature, thereby ensuring excellent luminance and recombination efficiency. This simple way to adjust charge injection balance requires no additional modification of the device architecture. [ABSTRACT FROM AUTHOR]

Quasi‐two‐dimensional (quasi‐2D) perovskites are attracting much attention due to their impressive luminescence properties. However, the introduction of insulating bulky cations reduces the charge transport property of mixed‐dimensional perovskites and leads to lowered brightness and increased turn‐on voltage. The trade‐off between high photoluminescence quantum yield (PLQY) and electrical conductivity should be well manipulated to obtain high‐performance perovskite light‐emitting diodes (PeLEDs). Herein, quasi‐2D perovskite BA2(CsPbBr3)n‐1PbBr4‐PEO with high PLQY and excellent carrier injection efficiency is demonstrated by incorporating bulky n‐butylammonium bromide (BABr), CsPbBr3, and polyethylene oxide (PEO). BA can intercalate into the three‐dimensional perovskite framework to form a layered (quasi‐2D) perovskite structure. The ion conductive polymer PEO is used to protect quasi‐2D perovskite crystals. Additional BABr is removed by using anhydrous isopropyl alcohol as a washing agent due to its selective dissolubility. By carefully modulating the optical and electrical properties of quasi‐2D perovskite films, the maximum luminance of PeLEDs is dramatically enhanced from 191 to 33533 cd m−2, which is the brightest green quasi‐2D PeLED reported thus far, leading to an increase in external quantum efficiency from 1.81% to 8.42%. This work provides a promising route to control the optical and electrical properties of quasi‐2D perovskite films for high‐performance optoelectronic devices. A quasi‐2D perovskite with high photoluminescence quantum yield and excellent carrier injection efficiency is demonstrated by incorporating n‐butylammonium bromide, CsPbBr3 and polyethylene oxide. By modulating the optical and electrical properties of quasi‐2D perovskite films, the maximum luminance of PeLEDs is dramatically enhanced from 191 to 33 533 cd m−2, which is the brightest value yet observed for green quasi‐2D PeLEDs. [ABSTRACT FROM AUTHOR]

Colloidal quantum dots light‐emitting diodes (QD‐LEDs) have been investigated for several decades. Compared with their green and red counterparts, the hole injection is more difficult for blue QDs due to their large optical band gap and relatively low highest occupied molecular orbital level. High‐performance blue QD‐LEDs are demonstrated by inserting a thin deoxyribonucleic acid (DNA) buffer layer between hole transport layer and ZnCdS/ZnS core/shell QDs layer. This DNA buffer layer can effectively enhance the hole injection efficiency, meanwhile its high lowest unoccupied molecular orbital level can help the injected electrons to be confined in the emitting layer, thus ensuring the charge balance in the QDs layer and an excellent recombination efficiency. After utilizing DNA as buffer layer, the maximum luminance is significantly increased from 10 218 to 16 655 cd m−2 and the external quantum efficiency is increased from 4.39% to 5.65%. These devices provide a saturated blue emission with emission peak located at 462 nm and full width at half maximum of 21 nm. This saturated blue emission makes it suitable for commercial applications. The results indicate that DNA is a promising material for regulating charge balance in the emitting layer for manufacturing high performance QD‐LEDs. Highly luminescent blue quantum‐dot (QD) light‐emitting diodes are successfully fabricated by introducing a thin deoxyribonucleic acid (DNA) interlayer between the hole transport layer and QDs emitting layer. The DNA buffer layer can effectively enhance the hole injection efficiency and confine the electrons in the emitting layer, thus ensuring the charge balance in the QDs layer and an excellent recombination efficiency. [ABSTRACT FROM AUTHOR]

Light management is important for improving light absorption within active layers in polymer solar cells (PSCs). Electrode buffer layers play an important role in modulating the distribution of optical electric filed within the photoactive layer. Herein, the authors employ solution‐processed WOx or ReOx to substitute the acidic poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as the anode buffer layer and ZrAcac or HfAcac to replace Mg as the cathode buffer layer. Optical transfer matrix formalism simulation is used to model the absorption spectra, exciton generation rate, and optical electric field distribution of devices. Simulated results shows that stronger absorption, quicker exciton generation rate, and more reasonable photoelectric field distribution can be achieved in the photoactive layer with solution‐processed buffer layer modification, which results in a higher short‐circuit current density (Jsc). Under the guidance of theoretical simulation, the device with architecture of ITO/WOx/PTB7‐Th:PC71BM/HfAcac/Al is optimized. Compared with the traditional PEDOT:PSS‐Mg based device, the Jsc is increased from 16.60 to 18.61 mA cm−2 and the best power conversion efficiency (PCE) is increased from 9.02% to 10.60% for the device with WOx‐HfAcac modification, which is among the best values reported for fullerene‐based PSCs. The good agreement between simulated and experimental results indicates that optical model is a useful tool for device design and optimization. Optical transfer matrix formalism simulation is used to model the absorption spectra, exciton generation rate, and optical electric field distribution of the polymer solar cells based on PTB7‐Th:PC71BM. High performance devices are obtained under the guidance of optical transfer matrix formalism simulation. An optimum PCE of 10.60% is obtained with the device based on the WOx‐HfAcac buffer layer. [ABSTRACT FROM AUTHOR]