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Interface engineering has become the mainstream for improving the performance of perovskite solar cells (PSCs). Interfacial dipole (ID) molecules have emerged as a feasible and effective strategy to alleviate the charge carrier loss and energy loss in PSCs. Here, the three symmetrical donor–acceptor interfacial dipole molecules (named PzT, PzTE, and PzTN) are designed and synthesized with identical hole transport backbone and different anchoring groups. The ID molecule is introduced into the interface between the perovskite layer and the hole transport layer. The dipole moments of ID molecules regulate the surface work function and energy‐level alignment of perovskites, improve charge extraction, and reduce energy loss at the interface. Meanwhile, the anchoring groups of ID molecules coordinate with the defects on the surface of PVK and HTL, reduce interfacial trap state density and charge accumulation, and mitigate the carrier non‐radiative recombination losses. As a result, PzTN‐modified PSC achieved a champion power conversion efficiency of 25.34% with a photovoltage of 1.176 V and a fill factor (FF) of 83.27%, accompanied by almost undetectable hysteresis and excellent operating stability. This research demonstrates a feasible strategy for efficient and stable PSCs by interfacial dipole molecules. [ABSTRACT FROM AUTHOR]

Peripheral nerve block is performed for precise pain control and lesser side effects after surgery by reducing opioid consumption. Injectable hydrogel delivery systems with high biosafety and moisture content have good clinical application prospects for local anesthetic delivery. However, how to achieve high drug loading and long‐term controlled release of water‐soluble narcotic drugs remains a big challenge. In this study, heterogeneous microspheres and an injectable gel‐matrix composite drug delivery system are designed in two steps. First, heterogeneous hydrogel microspheres loaded with ropivacaine (HMS‐ROP) are prepared using a microfluidic chip and in situ alkalization. An injectable self‐healing hydrogel matrix (Gel) is then prepared from modified carboxymethylcellulose (CMC‐ADH) and oxidized hyaluronic acid (OHA). A local anesthetic delivery system, Gel/HMS‐ROP/dexmedetomidine (DEX), with long‐term retention and drug release in vivo is prepared by combining HMS‐ROP and Gel/DEX. The drug loading of HMS‐ROP reached 41.1%, with a drug release time of over 160 h in vitro, and sensory and motor blockade times in vivo of 48 and 36 h, respectively. In summary, the sequential release and synergistic analgesic effects of the two anesthetics are realized using core‐shell microspheres, DEX, and an injectable gel, providing a promising strategy for long‐acting postoperative pain management. [ABSTRACT FROM AUTHOR]

The key to advancing lithium‐ion battery (LIB) technology, particularly with respect to the optimization of cycling protocols, is to obtain comprehensive and in‐depth understanding of the dynamic electrochemical processes during battery operation. This work shows that pulse current (PC) charging substantially enhances the cycle stability of commercial LiNi0.5Mn0.3Co0.2O2 (NMC532)/graphite LIBs. Electrochemical diagnosis unveils that pulsed current effectively mitigates the rise of battery impedance and minimizes the loss of electrode materials. Operando and ex situ Raman and X‐ray absorption spectroscopy reveal the chemical and structural changes of the negative and positive electrode materials during PC and constant current (CC) charging. Specifically, Li‐ions are more uniformly intercalated into graphite and the Ni element of NMC532 achieves a higher energy state with less Ni─O bond length variation under PC charging. Besides, PC charging suppresses the electrolyte decomposition and continuous thickening of the solid‐electrolyte‐interphase (SEI) layer on graphite anode. These findings offer mechanistic insights into Li‐ion storage in graphite and NMC532 and, more importantly, the role of PC charging in enhancing the battery cycling stability, which will be beneficial for advancing the cycling protocols for future LIBs and beyond. [ABSTRACT FROM AUTHOR]

Developing polymers with high electrical conductivity (σ) after n‐doping is a great challenge for the advance of the field of organic thermoelectrics (OTEs). Herein, we report a series of thiazole imide‐based n‐type polymers by gradually increasing selenophene content in polymeric backbone. Thanks to the strong intramolecular noncovalent N⋅⋅⋅S interaction and enhanced intermolecular Se⋅⋅⋅Se interaction, with the increase of selenophene content, the polymers show gradually lowered LUMOs, more planar backbone, and improved film crystallinity versus the selenophene‐free analogue. Consequently, polymer PDTzSI−Se with the highest selenophene content achieves a champion σ of 164.0 S cm−1 and a power factor of 49.0 μW m−1 K−2 in the series when applied in OTEs after n‐doping. The σ value is the highest one for n‐type donor‐acceptor OTE materials reported to date. Our work indicates that selenophene substitution is a powerful strategy for developing high‐performance n‐type OTE materials and selenophene incorporated thiazole imides offer an excellent platform in enabling n‐type polymers with high backbone coplanarity, deep‐lying LUMO and enhanced mobility/conductivity. [ABSTRACT FROM AUTHOR]

As productive and essential ecosystems, coastal wetlands have experienced increased environmental impacts such as saltwater intrusion and eutrophication, resulting in significant shifts in microbially mediated ecosystem functions, such as carbon sequestration and nutrient transformations. The soil microbial respiration, a primary process in the transfer of carbon from soil to the atmosphere, is susceptible to environmental changes. However, studies on how salinity affects soil microbial respiration in coastal wetlands have not been fully explored. Soil samples were systematically collected from divergent sampling sites covering medium‐ and extremely‐saline wetlands along a river‐estuary‐coast continuum to investigate mechanisms controlling soil microbial respiration in coastal wetlands. According to the results, the microbial biomass and carbon‐related extracellular enzyme activities were significantly lower in extremely saline (ECe >15 ds m−1, ES) than medium and highly saline soils (ECe <15 ds m−1, MHS) (p < 0.05), indicating a suppressive effect of salinity on soil microbiota. Meanwhile, high‐salinity soils had lower vector length and soil microbial respiration rates, suggesting that soils with low carbon limitation might cause less carbon loss under higher salinity environments. Moreover, it was showed that increased available phosphorus could alleviate microbial carbon limitations. Changes in the microbial functional community demonstrated that the microbial community in favor of metabolic mediates and secondary metabolites substrates (regarded as labile substrates) were more sensitive to salinity. The partial least square path modeling further confirmed that microbial nutrient limitation and microbial biomass contribute more directly to promoting soil microbial respiration. These results have substantial implications for elucidating carbon dynamics in coastal wetlands ecosystems under increased nutrient discharge and sea‐level rise. [ABSTRACT FROM AUTHOR]

BACKGROUND: Plant invasions are a global concern. In eastern China, bamboo is rapidly expanding, negatively influencing neighbouring forest communities. However, studies on how bamboo invasion affects belowground communities, especially for soil invertebrates, are still lacking. In the present study, we focused on a highly abundant and diverse fauna taxon – Collembola. Collembola communities have three typical life‐forms (i.e., epedaphic, hemiedaphic, and euedaphic) inhabiting different soil layers and playing distinct roles in ecological processes. Specifically, we studied their abundance, diversity, and community composition at the three stages of bamboo invasion: uninvaded secondary broadleaf forest, moderately invaded mixed bamboo forest, and completely invaded bamboo (Phyllostachys edulis) forest. RESULTS: Our results showed that bamboo invasion negatively influenced Collembola communities by decreasing their abundance and diversity. Moreover, Collembola life‐forms differed in their responses to bamboo invasion, with surface‐dwelling Collembola being more vulnerable to bamboo invasion than soil‐living Collembola. CONCLUSION: Our findings indicate differential response patterns to bamboo invasion within Collembola communities. The negative effects of bamboo invasion on soil surface‐dwelling Collembola may further influence ecosystem functioning. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Designing n‐type polymers with high electrical conductivity remains a major challenge for organic thermoelectrics (OTEs). Herein, by devising a novel selenophene‐based electron‐deficient building block, the pronounced advantages of selenium substitution in simultaneously enabling advanced n‐type polymers is demonstrated with high mobility (≈2 orders of magnitude higher versus their sulfur‐based analogues due to both intensified intra‐ and inter‐chain interactions) and much improved n‐doping efficiency (enabled by the largely lowered LUMO level with a ≈0.2 eV margin) of the resulting polymers. Via side chain optimization and donor engineering, the selenium‐substituted polymer, f‐BSeI2TEG‐FT, achieves a highest conductivity of 103.5 S cm−1 and power factor of 70.1 µW m−1 K−2, which are among the highest values reported in literature for n‐type polymers, and f‐BSeI2TEG‐FT greatly outperformed the sulfur‐based analogue polymer by 40% conductivity increase. These results demonstrate that selenium substitution is a very effective strategy for improving n‐type performance and provide important structure‐property correlations for developing high‐performing n‐type OTE materials. [ABSTRACT FROM AUTHOR]

n‐Type semiconducting polymers with high thermoelectric performance remain challenging due to the scarcity of molecular design strategy, limiting their applications in organic thermoelectric (OTE) devices. Herein, we provide a new approach to enhance the OTE performance of n‐doped polymers by introducing acceptor‐acceptor (A‐A) type backbone bearing branched ethylene glycol (EG) side chains. When doped with 4‐(2,3‐dihydro‐1,3‐dimethyl‐1H‐benzimidazol‐2‐yl)‐N,N‐dimethylbenzenamine (N‐DMBI), the A‐A homopolymer PDTzTI‐TEG exhibits n‐type electrical conductivity (σ) up to 34 S cm−1 and power factor value of 15.7 μW m−1 K−2. The OTE performance of PDTzTI‐TEG is far greater than that of homopolymer PBTI‐TEG (σ=0.27 S cm−1), indicating that introducing electron‐deficient thiazole units in the backbone further improves the n‐doping efficiency. These results demonstrate that developing A‐A type polymers with EG side chains is an effective strategy to enhance n‐type OTE performance. [ABSTRACT FROM AUTHOR]

Plant roots significantly influence soil microbial diversity, and soil microorganisms play significant roles in both natural and agricultural ecosystems. Although the genetically modified (GM) crops with enhanced insect and herbicide resistance are thought to have unmatched yield and stress resistance advantages, thorough and in‐depth case studies still need to be carried out in a real‐world setting due to the potential effects of GM plants on soil microbial communities. In this study, three treatments were used: a recipient soybean variety Jack, a triple transgenic soybean line JD321, and the glyphosate‐treated JD321 (JD321G). Three sampling stages (flowering, seed filling and maturing), as well as three host niches of soybean rhizosphere [intact roots (RT), rhizospheric soil (RS) and surrounding soil (SS)] were established. In comparison to Jack, the rhizospheric soil of JD321G had higher urease activity and lower nitrite reductase at the flowering stage. Different treatments and different sampling stages existed no significant effects on the compositions of microbial communities at different taxonomic levels. However, at the genus level, the relative abundance of three plant growth‐promoting fungal genera (i.e. Mortierella, Chaetomium and Pseudombrophila) increased while endophytic bacteria Chryseobacterium and pathogenic bacteria Streptomyces decreased from the inside to the outside of the roots (i.e. RT → RS → SS). Moreover, two bacterial genera, Bradyrhizobium and Ensifer were more abundant in RT than in RS and SS, as well as three species, Agrobacterium radiobacter, Ensifer fredii and Ensifer meliloti, which are closely related to nitrogen‐fixation. Furthermore, five clusters of orthologous groups (COGs) associated to nitrogen‐fixation genes were higher in RT than in RS, whereas only one COG annotated as dinitrogenase iron‐molybdenum cofactor biosynthesis protein was lower. Overall, the results imply that the rhizosphere host niches throughout the soil–plant continuum largely control the composition and function of the root‐associated microbiome of triple transgenic soybean. [ABSTRACT FROM AUTHOR]

Dopant‐free hole‐transporting layers (HTLs) are highly desired for realizing efficient and stable perovskite solar cells (PVSCs), but only very few of them can enable power conversion efficiencies (PCEs) over 20%. Herein, two imide‐functionalized triarylamine‐based donor‐acceptor (D‐A) type copolymers, PBTI‐TPA and PTTI‐TPA, are developed and applied as dopant‐free HTLs in inverted PVSCs. The combination of a classic redox‐active triphenylamine donor unit and an electron‐withdrawing oligothiophene imide co‐unit with rigid and planar backbone furnishes the two polymers with quasi‐planar backbone, suitable frontier molecular orbital (FMO) energy levels, favorable thermal stability, appropriate film morphology, and passivation effect. More importantly, the greatly improved hole mobility renders them as promising HTLs for PVSCs. As a result, the undoped PTTI‐TPA‐based inverted PVSCs deliver a remarkable PCE up to 21% as well as negligible hysteresis and substantial long‐term stability, outperforming the devices based on PBTI‐TPA and PTAA. The performance also represents one of the highest PCEs reported to date for PVSCs based on dopant‐free polymeric HTLs. The results highlight the great potentials of oligothiophene imides for constructing donor‐acceptor polymeric HTLs for enabling high‐performance dopant‐free PVSCs. [ABSTRACT FROM AUTHOR]

High‐performance nonfullerene ternary organic solar cells (OSCs) with two polymer donors are less frequently reported because of the limited numbers of efficient polymer donors with good compatibility. Herein, a wide‐bandgap polymer P1 with a deep‐lying highest occupied molecular orbital (HOMO) level is incorporated as the third component into the benchmark PM6:Y6 binary system to fabricate ternary OSCs. The introduction of P1 not only leads to extended absorption coverage and forms a cascade‐like energy level alignment but also shows excellent compatibility with PM6, resulting in a favorable morphology in the ternary blend. More importantly, P1 possesses a deeper HOMO level (−5.6 eV) than most well‐known donor polymers, which enables resulting ternary OSCs with an improved open‐circuit voltage. As a result, the optimized ternary OSCs with 40 wt% P1 in donors achieve a power conversion efficiency (PCE) of 16.2% with a small nonradiative recombination loss of 0.23 eV, which is among the highest values of ternary OSCs based on two polymer donors. In addition, the ternary OSCs show a broad composition tolerance with a high PCE of over 14% throughout the whole blend ratios. These results provide an effective approach to fabricate efficient ternary OSCs by synergizing two wide‐bandgap polymer donors. [ABSTRACT FROM AUTHOR]

Individual effects of co‐occurring global change factors on net primary productivity (NPP) have been widely studied; however, their interactive effects remain highly debated.Here, we conducted a global meta‐analysis based on 919 multifactor observations from 120 published studies to examine the interactive effects on NPP of global change factors including elevated [CO2], warming, nitrogen addition, irrigation, drought and changes in species diversity.On average, of the factors studied, six pairs of factors had additive and two pairs had synergistic interactions. Importantly, some of those interaction types changed over time and with treatment intensity. The synergistic interaction between elevated [CO2] and nitrogen addition became additive at high nitrogen addition rates, whereas the synergistic interaction between irrigation and warming diminished at higher temperatures. Over time, the additive effect between elevated [CO2] and increased species richness switched to synergistic. Other global change factor pairs—including elevated [CO2] and warming, nitrogen addition and increased richness, irrigation and N addition, as well as drought and increased richness—remained additive regardless of their treatment intensity or experimental duration. Interaction types of those global change factor pairs did not vary with ecosystem types assessed in our study.Synthesis. Our results suggest that the assumptions of static effects through time or ignoring treatment intensity effects will provide inaccurate predictions of the interactive effects of global change factors on terrestrial NPP. Understanding the context‐dependent nature of interactive effects is crucial for validating Earth system models and predicting future NPP responses to co‐occurring global change drivers. [ABSTRACT FROM AUTHOR]