Grain size is an important component trait of grain yield, which is frequently threatened by abiotic stress. However, little is known about how grain yield and abiotic stress tolerance are regulated. ...Here, we characterize GSA1, a quantitative trait locus (QTL) regulating grain size and abiotic stress tolerance associated with metabolic flux redirection. GSA1 encodes a UDP-glucosyltransferase, which exhibits glucosyltransferase activity toward flavonoids and monolignols. GSA1 regulates grain size by modulating cell proliferation and expansion, which are regulated by flavonoid-mediated auxin levels and related gene expression. GSA1 is required for the redirection of metabolic flux from lignin biosynthesis to flavonoid biosynthesis under abiotic stress and the accumulation of flavonoid glycosides, which protect rice against abiotic stress. GSA1 overexpression results in larger grains and enhanced abiotic stress tolerance. Our findings provide insights into the regulation of grain size and abiotic stress tolerance associated with metabolic flux redirection and a potential means to improve crops.
Electrocatalytic water splitting is one of the sustainable and promising strategies to generate hydrogen fuel but still remains a great challenge because of the sluggish anodic oxygen evolution ...reaction (OER). A very effective approach to dramatically decrease the input cell voltage of water electrolysis is to replace the anodic OER with hydrazine oxidation reaction (HzOR) due to its lower thermodynamic oxidation potential. Therefore, developing the low‐cost and efficient HzOR catalysts, coupled with the cathodic hydrogen evolution reaction (HER), is tremendously important for energy‐saving electrolytic hydrogen production. Herein, a new‐type of copper–nickel nitride (Cu1Ni2‐N) with rich Cu4N/Ni3N interface is rationally constructed on carbon fiber cloth. The 3D electrode exhibits extraordinary HER performance with an overpotential of 71.4 mV at 10 mA cm−2 in 1.0 m KOH, simultaneously delivering an ultralow potential of 0.5 mV at 10 mA cm−2 for HzOR in a 1.0 m KOH/0.5 m hydrazine electrolyte. Moreover, the electrolytic cell utilizing the synthesized Cu1Ni2‐N electrode as both the cathode and anode display a cell voltage of 0.24 V at 10 mA cm−2 with an excellent stability over 75 h. The present work develops the promising copper–nickel‐based nitride as a bifunctional electrocatalyst through hydrazine‐assistance for energy‐saving electrolytic hydrogen production.
A new type of copper–nickel nitride porous nanosheet with a rich Cu4N/Ni3N interface supported on carbon fiber cloth is synthesized for the first time. The bifunctional catalyst electrode exhibits both outstanding performance for hydrogen evolution reaction and hydrazine oxidation reaction, making it a promising candidate for energy saving electrolytic hydrogen production.
Metal‐halide perovskite solar cells (PSCs) exhibit outstanding power conversion efficiencies (PCEs) when fabricated as mm‐sized devices, but creation of high‐performing large‐area modules that are ...stable on a sufficiently long timescale still presents a significant challenge. Herein, the quality of large‐area perovskite film is improved by using ionic liquid additives via forming a new Pb‐N bonding between the ionic liquid and Pb2+. This new bond can be modulated by a critical screening of the anion structure of the ionic liquid. The selected ionic liquid effectively reduces the defects of the perovskite films and markedly elongate their carrier lifetimes. As a result, a champion PCE of 24.4% for small‐area (0.148 cm2) devices and 20.4% for larger‐area (10.0 cm2) modules under AM 1.5G irradiation is achieved. More importantly, the modified devices retain 90% of their peak PCE after aging for 1900 h at 65 ± 5 °C (ISOS‐T‐1) and 80% after continuous light soaking for 750 h. The non‐encapsulated modules maintained 80% of their peak PCE after 1100 h of aging in the air with a relative humidity of 35 ± 5% and temperature of 25 ± 5 °C under dark (ISOS‐D‐1), showing great potential for future commercialization.
In this study, the quality of large‐area perovskite film is improved by using ionic liquid additives via forming a new Pb‐N bonding between the ionic liquid and Pb2+. A champion power conversion efficiency of 24.4% for small‐area (0.148 cm2) devices and 20.4% for larger‐area modules (10.0 cm2) are achieved. The devices and modules exhibit excellent long‐term stability.
Organic–inorganic hybrid halide perovskite solar cells (PSCs) have recently drawn enormous attentions due to their impressive performance (>22%) and low temperature solution processability (<150 °C). ...Current solution process involves application of a large amount of toxic solvents, such as chlorobenzene, which is heavily employed in both the perovskite layer and the hole transport layer (HTL) deposition. Herein, this study employs green solvent of ethyl acetate for engineering efficient perovskite and HTL layers, which enables a synergic interface (perovskite/HTL) optimization. A champion efficiency of 19.43% is obtained for small cells (0.16 cm2 with mask) and over 14% for large size modules (5 × 5 cm2). The PSCs prepared from the green solvent engineering demonstrate superior performance on both efficiency and stability over their chlorobenzene counterparts. These enhancements are ascribed to the in situ inhibition on carrier recombination induced by interfacial defects during the solution processing, which enables about 2/3 reduction of calculated recombination rate. Thus, the green solvent route shows the great potential toward environmental‐friendly manufacturing.
The widely used toxic chlorobenzene for the perovskite and Spiro‐OMeTAD film processing is replaced by a green solvent of ethyl acetate. This green solvent engineering produces pinhole‐free films of both the perovskite and Spiro‐OMeTAD hole transport layer. Via the synergic interface optimization, an impressive power conversion efficiency up to 19.43% is achieved.
Perovskite solar cells (PSCs) show great promise for next‐generation building‐integrated photovoltaic (BIPV) applications because of their abundance of raw materials, adjustable transparency, and ...cost‐effective printable processing. Owing to the complex perovskite nucleation and growth control, the fabrication of large‐area perovskite films for high‐performance printed PSCs is still under active investigation. Herein, the study proposes an intermediate‐phase‐transition‐assisted one‐step blade coating for an intrinsic transparent formamidinium lead bromide (FAPbBr3) perovskite film. The intermediate complex optimizes the crystal growth path of FAPbBr3, resulting in a large‐area, homogeneous, and dense absorber film. A champion efficiency of 10.86% with high open‐circuit voltage up to 1.57 V is obtained with a simplified device architecture of glass/FTO/SnO2/FAPbBr3/carbon. Moreover, the unencapsulated devices maintain 90% of their initial power conversion efficiency after aging at 75 °C for 1000 h in ambient air, and 96% after maximum power point tracking for 500 h. The printed semitransparent PSCs, with average visible light transmittance over 45%, demonstrate high efficiencies for both small devices (8.6%) and 10 × 10 cm2 modules (5.55%). Finally, the ability to customize the color, transparency, and thermal insulation properties of FAPbBr3 PSCs makes them high prospects as multifunctional BIPVs.
An in situ intermediate phase transition‐controlled blade‐coating method for FAPbBr3 perovskite solar cells is introduced, which obtains a high power conversion efficiency (PCE) of 10.86% based on hole transport layer‐free structures of glass/FTO/SnO2/FAPbBr3/carbon. Semitransparent devices are fabricated and obtain high PCE of 8.61% at average visible light transmittance (AVT) = 45% and PCE of 5.55% at AVT = 53% for small devices and 10 × 10 cm2 modules, respectively.
Organolead triiodide perovskite (CH3NH3PbI3) as a light-sensitive material has attracted extensive attention in optoelectronics. The reported perovskite photodetectors (PDs) mainly focus on the ...individual, which limits their spatial imaging applications. Uniform perovskite networks combining transparency and device performance were synthesized on poly(ethylene terephthalate) (PET) by controlling perovskite crystallization. Photodetector arrays based on above network were fabricated to demonstrate the potential for image mapping. The trade-off between the PD performance and transparency was systematically investigated and the optimal device was obtained from 30 wt % precursor concentration. The switching ratio, normalized detectivity, and equivalent dark current derived shot noise as the critical parameters of PD arrays reached 300, 1.02 × 1012 Jones, and 4.73 × 10–15A Hz–1/2, respectively. Furthermore, the PD arrays could clearly detect spatial light intensity distribution, thus demonstrating its preliminary imaging function. The perovskite network PD arrays fabricated on PET substrates could also conduct superior flexibility under wide angle and large number of bending. For the common problem of perovskite optoelectronics in stability, the perovskite networks sheathed with hydrophobic polymers greatly enhanced the device stability due to the improved interface contacts, surface passivation, and moisture isolation. Taking into consideration transparency, flexibility, imaging and stability, the present PD arrays were expected to be widely applied in visualized portable optoelectronic system.
The hot-phonon bottleneck effect in lead-halide perovskites (APbX
) prolongs the cooling period of hot charge carriers, an effect that could be used in the next-generation photovoltaics devices. ...Using ultrafast optical characterization and first-principle calculations, four kinds of lead-halide perovskites (A=FA
/MA
/Cs
, X=I
/Br
) are compared in this study to reveal the carrier-phonon dynamics within. Here we show a stronger phonon bottleneck effect in hybrid perovskites than in their inorganic counterparts. Compared with the caesium-based system, a 10 times slower carrier-phonon relaxation rate is observed in FAPbI
. The up-conversion of low-energy phonons is proposed to be responsible for the bottleneck effect. The presence of organic cations introduces overlapping phonon branches and facilitates the up-transition of low-energy modes. The blocking of phonon propagation associated with an ultralow thermal conductivity of the material also increases the overall up-conversion efficiency. This result also suggests a new and general method for achieving long-lived hot carriers in materials.
Sb2(SexS1 − x)3 alloy materials with tunable bandgaps combining the advantages of Sb2S3 and Sb2Se3 showed high potential in low cost, non‐toxicity, and high stability solar cells. The composition ...dependence of device performance becomes indispensable to study. However, traditional approaches often implement 1 composition at a time, which easily lead to long period and systematic errors. The present work developed a high‐throughput experimental method, close‐space dual‐plane‐source evaporation (CDE) method, to successfully deposit continuous composition spread Sb2(SexS1 − x)3 library at 1 time. On the surface of the obtained film, the x value of Se content evolved from 0.09 to 0.84 by a series of complementary characterizations. At depth direction, the alloy film kept high crystallinity and composition consistency. Solar cell arrays (19 × 6) were fabricated to investigate the relationship between compositions and performances. As the increase of Se content, the conversion efficiency first increased from 1.8% to 5.6% and then decreased to 5%. The Voc and Jsc demonstrated an opposite evolution trend. The champion device with the composition of Sb2(Se0.68S0.32)3 achieved the Voc and Jsc trade‐off exceeding the performances of Sb2S3 (2.43%) and Sb2Se3 (4.97%) devices. Cryogenic and transient characterizations were utilized to investigate the distinct performance evolution mechanism. There existed shallow defect levels in Se‐rich alloys and deep defects in sulfur‐rich ones. The widely tuned absorber compositions combined with distinct defect characters induced to the large variation of device performance. The present continuous composition spread Sb2(SexS1 − x)3 film and their CDE fabrication technique were expected to efficiently screen materials and promote the development of antimony chalcogenide solar cells.
To study composition dependence with device performance, the high‐throughput experimental method was designed to deposit continuous composition spread Sb2(SexS1 − x)3 library at one time. The x value evolved from 0.09 to 0.84 on the surface of alloy film. From solar cell arrays (19 × 6) with increased Se content, the conversion efficiency first increased from 1.8% to 5.6% and then decreased to 5%. The optimal composition Sb2(Se0.68S0.32)3 absorber owns more suitable bandgap, shallower defects and longer photocarrier lifetime.
3-Hydroxy butyrate dehydrogenase 2 (BDH2) is a short-chain dehydrogenase/reductase family member that plays a key role in the development and pathogenesis of human cancers. However, the role of BDH2 ...in gastric cancer (GC) remains largely unclear. Our study aimed to ascertain the regulatory mechanisms of BDH2 in GC, which could be used to develop new therapeutic strategies.
Western blotting, immunohistochemistry, and RT-PCR were used to investigate the expression of BDH2 in GC specimens and cell lines. Its correlation with the clinicopathological characteristics and prognosis of GC patients was analysed. Functional assays, such as CCK-8 and TUNEL assays, transmission electron microscopy, and an in vivo tumour growth assay, were performed to examine the proliferation, apoptosis, and autophagy of GC cells. Related molecular mechanisms were clarified by luciferase reporter, coimmunoprecipitation, and ubiquitination assays.
BDH2 was markedly downregulated in GC tissues and cells, and the low expression of BDH2 was associated with poor survival of GC patients. Functionally, BDH2 overexpression significantly induced apoptosis and autophagy in vitro and in vivo. Mechanistically, BDH2 promoted Keap1 interaction with Nrf2 to increase the ubiquitination level of Nrf2. Ubiquitination/degradation of Nrf2 inhibited the activity of ARE to increase accumulation of reactive oxygen species (ROS), thereby inhibiting the phosphorylation levels of Akt
and mTOR
.
Our study indicates that BDH2 is an important tumour suppressor in GC. BDH2 regulates intracellular ROS levels to mediate the PI3K/Akt/mTOR pathway through Keap1/Nrf2/ARE signalling, thereby inhibiting the growth of GC.
Transmission electron microscopy (TEM) is a powerful tool for unveiling the structural, compositional, and electronic properties of organic–inorganic hybrid perovskites (OIHPs) at the atomic to ...micrometer length scales. However, the structural and compositional instability of OIHPs under electron beam radiation results in misunderstandings of the microscopic structure–property–performance relationship in OIHP devices. Here, ultralow dose TEM is utilized to identify the mechanism of the electron‐beam‐induced changes in OHIPs and clarify the cumulative electron dose thresholds (critical dose) of different commercially interesting state‐of‐the‐art OIHPs, including methylammonium lead iodide (MAPbI3), formamidinium lead iodide (FAPbI3), FA0.83Cs0.17PbI3, FA0.15Cs0.85PbI3, and MAPb0.5Sn0.5I3. The critical dose is related to the composition of the OIHPs, with FA0.15Cs0.85PbI3 having the highest critical dose of ≈84 e Å−2 and FA0.83Cs0.17PbI3 having the lowest critical dose of ≈4.2 e Å−2. The electron beam irradiation results in the formation of a superstructure with ordered I and FA vacancies along c, as identified from the three major crystal axes in cubic FAPbI3, c, c, and c. The intragrain planar defects in FAPbI3 are stable, while an obvious modification is observed in FA0.83Cs0.17PbI3 under continuous electron beam exposure. This information can serve as a guide for ensuring a reliable understanding of the microstructure of OIHP optoelectronic devices by TEM.
Transmission‐electron‐microscopy‐based characterization techniques are expected to play a significant role in revealing the structural, compositional, and electronic properties of organic–inorganic hybrid perovskite materials and optoelectronic devices. However, perovskites are unstable and highly sensitive to electron beam radiation. This paper has outlined key guidelines for imaging the intrinsic structure of organic–inorganic hybrid perovskite materials.
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