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Zinc pnictides, particularly Zn3As2, hold significant promise for optoelectronic applications owing to their intrinsic p-type behavior and appropriate bandgaps. However, despite the outstanding properties of colloidal Zn3As2 nanocrystals, research in this area is lacking because of the absence of suitable precursors, occurrence of surface oxidation, and intricacy of the crystal structures. In this study, a novel and facile solution-based synthetic approach is presented for obtaining highly crystalline p-type Zn3As2 nanocrystals with accurate stoichiometry. By carefully controlling the feed ratio and reaction temperature, colloidal Zn3As2 nanocrystals are successfully obtained. Moreover, the mechanism underlying the conversion of As precursors in the initial phases of Zn3As2 synthesis is elucidated. Furthermore, these nanocrystals have been employed as active layers in field-effect transistors that exhibit inherent p-type characteristics with native surface ligands. To enhance the charge transport properties, a dual passivation strategy is introduced via phase-transfer ligand exchange, leading to enhanced hole mobilities as high as 0.089 cm2 V–1 s–1. This study not only contributes to the advancement of nanocrystal synthesis, but also opens up new possibilities for previously underexplored p-type nanocrystal research.

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The controlled synthesis of RuMo alloy nanoflowers (NFs) with unconventional face-centered cubic (fcc) phase and hexagonal close-packed (hcp)/fcc heterophase is well achieved. Notably, fcc RuMo NFs demonstrate superior catalytic performance toward nitrate electroreduction to ammonia than hcp/fcc RuMo NFs. Mechanism studies reveal that crystal phase engineering of RuMo alloy nanostructures can significantly improve the electroactivity.

Electrocatalytic nitrate reduction reaction (NO3RR) toward ammonia synthesis is recognized as a sustainable strategy to balance the global nitrogen cycle. However, it still remains a great challenge to achieve highly efficient ammonia production due to the complex proton-coupled electron transfer process in NO3RR. Here, the controlled synthesis of RuMo alloy nanoflowers (NFs) with unconventional face-centered cubic (fcc) phase and hexagonal close-packed/fcc heterophase for highly efficient NO3RR is reported. Significantly, fcc RuMo NFs demonstrate high Faradaic efficiency of 95.2% and a large yield rate of 32.7 mg h−1 mgcat −1 toward ammonia production at 0 and −0.1 V (vs reversible hydrogen electrode), respectively. In situ characterizations and theoretical calculations have unraveled that fcc RuMo NFs possess the highest d-band center with superior electroactivity, which originates from the strong Ru─Mo interactions and the high intrinsic activity of the unconventional fcc phase. The optimal electronic structures of fcc RuMo NFs supply strong adsorption of key intermediates with suppression of the competitive hydrogen evolution, which further determines the remarkable NO3RR performance. The successful demonstration of high-performance zinc-nitrate batteries with fcc RuMo NFs suggests their substantial application potential in electrochemical energy supply systems.

Although a suitable vertical phase separation (VPS) morphology is essential for improving charge transport efficiency, reducing charge recombination, and ultimately boosting the efficiency of organic solar cells (OSCs), there is a lack of theoretical guidance on how to achieve the ideal morphology. Herein, we established a relationship between the molecular structure and the VPS morphology of pseudo-planar heterojunction (PPHJ) OSCs by using molecular surface electrostatic potential (ESP) as a bridge. We revealed the morphological evolution mechanism by studying four binary systems with vary electrostatic potential difference (∆ESP) between donors and acceptors. Our findings manifest that as ∆ESP increases, the active layer is more likely to form a well-mixed phase, while a smaller ∆ESP favors VPS morphology. Interestingly, we also observed that a larger ∆ESP led to enhanced miscibility between donors and acceptors, resulting in higher non-radiative energy losses (ΔE3). Based on these discoveries, we meticulously designed a ternary PPHJ device with an appropriate ∆ESP to obtain better VPS morphology and lower ΔE3, and achieve an impressive efficiency of 19.09%. Our work demonstrates that by optimizing the ΔESP, we can not only control the formation of VPS morphology but also reduce energy losses, paving the way to further boost OSC performance.

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Bandstructure engineering using alloying is widely utilised for achieving optimised performance in modern semiconductor devices. While alloying has been studied in monolayer transition metal dichalcogenides, its application in van der Waals heterostructures built from atomically thin layers is largely unexplored. Here, we fabricate heterobilayers made from monolayers of WSe2 (or MoSe2) and MoxW{1}Se2 alloy and observe nontrivial tuning of the resultant bandstructure as a function of concentration x. we monitor this evolution by measuring the energy of photoluminescence (PL) of the interlayer exciton (IX) composed of an electron and hole residing in different monolayers. In MoxW{1}Se2/WSe2, we observe a strong IX energy shift of 100 meV for varied from 1 to 0.6. However, for 0.6 this shift saturates and the IX PL energy asymptotically approaches that of the indirect bandgap in bilayer WSe2. we theoretically interpret this observation as the strong variation of the conduction band K valley for 0.6, with IX PL arising from the K transition, while for 0.6, the bandstructure hybridization becomes prevalent leading to the dominating momentum-indirect KQ transition. This bandstructure hybridization is accompanied with strong modification of IX PL dynamics and nonlinear exciton properties. our work provides foundation for bandstructure engineering in van der Waals heterostructures highlighting the importance of hybridization effects and opening a way to devices with accurately tailored electronic properties.