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Controllable designing of heteroatom-doped carbon catalysts provides an insightful strategy for boosting the performance and kinetics of the oxygen reduction/evolution reaction (ORR/OER). However, the role of oxygen species is usually omitted. Herein, a facile oxygen engineering strategy is proposed to tune the oxygen species in N-doped porous carbon nanofibers (NPCNFs-O) via a facile electrospinning method, in which βcyclodextrin acts as the pore inducer and oxygen regulator. Benefitting from the large specific surface area and synergistic effect of N,O codoping, the NPCNF-O catalyst exhibits superior ORR (E 1/2 = 0.85 V vs reversible hydrogen electrode (RHE)) and OER (E j = 10 = 1.556 V vs RHE) activities with excellent stability. Both experimental and theoretical calculations verify the crucial role of carboxyl groups, which regulate the local charge density and reduce the reaction energy barrier for enhancing the oxygen electrocatalytic activity. Moreover, a rechargeable zinc−air battery using NPCNF-O as the air cathode demonstrates a maximum power density of 125.1 mW cm −2 and long-term durability. Importantly, NPCNF-O can be served as an integrated freestanding electrode for portable zinc−air batteries. The work brings brilliant fundamental insights for constructing efficient metal-free carbon material catalysts for future energy conversion and storage systems.

A high-mobility diketopyrrolopyrrole-based copolymer (P) was employed in compact layer free CH3NH3PbI3 perovskite solar cells as a hole-transporting layer (HTL). By using the P-HTL, the 6.62% device efficiency with conventional poly-3-hexylthiophene was increased to 10.80% in the simple device configuration (ITO/CH3NH3PbI3/HTL/MoO3/Ag). With improved short circuit current density, open circuit voltage, and fill factor, the higher power conversion efficiency of P-HTL device is ascribed to the higher carrier mobility, more suitable energy level, and lower interfacial charge recombination. Advantages of applying P-HTL to perovskite solar cells, such as low cost, low-temperature processing, and excellent performance with simple cell structure, exhibit a possibility for commercial applications.

Freestanding graphene membranes were successfully functionalized with platinum nanoparticles (Pt NPs). High-resolution transmission electron microscopy revealed a homogeneous distribution of single-crystal Pt NPs that tend to exhibit a preferred orientation.Unexpectedly, the NPs were also found to be partially exposed to the vacuum with the top Pt surface raised above the graphene substrate, as deduced from atomic-scale scanning tunneling microscopy images and detailed molecular dynamics simulations. Local strain accumulation during the growth process is thought to be the origin of the NP self-organization. These findings

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Green mold caused by Penicillium digitatum is one of the most serious postharvest diseases of citrus fruit, and it is ubiquitous in all citrus growing regions in the world. Sterol 14α-demethylase (CYP51) is one of the key enzymes of sterol biosynthesis in the biological kingdom and a prime target of antifungal drugs. Mutations in CYP51s have been found to be correlated with resistance to azole fungicides in many fungal species. To investigate the mechanism of resistance to prochloraz (PRC) in P. digitatum, the PRC sensitivity was determined in vitro in this study to assess the sensitivity of 78 P. digitatum isolates collected in Hubei province. The results showed that 25 isolates were prochloraz-resistant (PRC-R), including six high-resistant (HR) strains, twelve medium-resistant (MR) and seven low-resistant (LR) strains. A sequence analysis showed no consistent point mutations of PdCYP51A in the PRC-R strains, but four substitutions of CYP51B were found, Q309H in LR strains, Y136H and Q309H in HR strains, and G459S and F506I in MR strains, which corresponded to the four sensitivity levels. Based on the sequence alignment analysis and homology modeling followed by the molecular docking of the PdCYP51B protein, the potential correlation between the mutations and PRC resistance is proposed.

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Recently, binary transition metal oxides, phosphates, and sulfides have attracted wide attention due to their potential applications in supercapacitors. The emergence of metal‐organic frameworks (MOFs) provides new opportunities for the synthesis and investigation of porous binary metal compounds with similar microstructures. Herein, binary metal oxide (NiCo‐O) tubular structures are derived from NiCo‐MOF‐74 via a facile annealing process, and then phosphate (NiCo‐P) and sulfide (NiCo‐S) structures are obtained from NiCo‐O by heat treatment and solvothermal process, respectively. Among the three derivatives, NiCo‐S with nanosheet structures has the highest specific capacitance of 930.4 F g−1 at a current density of 1 A g−1 and an excellent rate capability with a retention of ≈80% at 10 A g−1. The long‐term cycling performance of NiCo‐S is superior with 70.5% retention after 10 000 cycles. The hybrid supercapacitor device with NiCo‐S and activated carbon as positive and negative electrodes delivers a high energy density of 22.6 W h kg−1 at a power density of 800 W kg−1. The excellent performance of NiCo‐S can be attributed to its nanosheet structure, which increases the specific surface area and electroactive sites.