A carrot-inspired solar thermal evaporator exhibits a water evaporation rate of 2.04 kg m−2 h−1 and an outstanding durability and stability.

Introducing oxygen vacancy (V o ) has been considered as an effective and significant method to accelerate the sluggish electrocatalytic nitrogen reduction reaction (NRR). In this work, a series of bimetallic zeolitic imidazolate frameworks based on ZIF-67 and ZIF-8 with varied ratios of Co/Zn have been applied as precursors to prepare V o -rich Zn-doped Co 3 O 4 nanopolyhedrons (Zn−Co 3 O 4 ) by a low-temperature oxidation strategy. Zn−Co 3 O 4 presents an ammonia yield of 22.71 μg h −1 mg cat.−1 with a high faradaic efficiency of 11.9% for NRR under ambient conditions. The remarkable catalytic performances are believed to result from the plentiful V o as the Lewis acid sites and electron-rich Co sites to promote the adsorption and dissociation of N 2 molecules. Remarkably, Zn−Co 3 O 4 also demonstrates a high electrochemical stability. This work presents a guiding method for developing a stable and efficient electrocatalyst for the NRR.

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The rapid development of highly integrated photonic circuits has been driving electro-optic (EO) devices to increasingly compact sizes, with the perspective of being able to control light at the nanoscale. However, tunability with spatial resolution below 10 nm scale with conventional approaches, such as metallic nanowires, remains a challenge. Here, we show a graphene-coated nanowire system aiming at beam spatial modulation at a deeply subwavelength scale. By analytically and numerically investigating the eigenmodal properties of this system, we found that beam power can propagate along either a swinging or a helical path in the hybrid nanowire. In particular, the period of the swing beam and the chirality and period of the helix beam can be flexibly controlled by tuning the chemical potential of graphene via the gate voltage. Significantly, due to its good modal confinement, such a beam can be independently manipulated even in the presence of another nanowire at a separation of 40 nm, which opens a realistic path toward gateprogrammable EO addressing or data storage with ultrahigh density (64 terabyte/μm). At the same time, by fulfilling the phase matching condition between the two supported guided modes operating at different wavelengths, either a full band or bandtunable terahertz wave at the nanoscale may be achieved by nonlinear difference frequency generation. Our proposed hybrid nanowire system opens interesting potentials to accomplish gate-programmable EO devices at sub-10 nm scale.

despite the advantages of being without outer energy, most self-powered photodetectors suffer from low photoresponsivity, hindering their commercial applications. Even with recent progresses, for those devices with relatively high responsivity, the slow response time remains another challenge. [14] Therefore, constructing a self-powered broadband photodetector with high responsivity and fast response time is of great importance.Antimony triselenide (Sb 2 Se 3 ), with advantages of suitable bandgap, [15] high absorption coefficient, excellent electronic properties, low toxicity, low cost, and relatively earth-abundant constituents, [16] has attracted great research attention for solar cells and photodetectors. [17][18][19] Vanadium oxides, especially VO 2 , are typical materials with strong electron correlations and metal-insulator transitions, which are promising for smart windows, optic switches, memories, etc. [20][21][22][23][24][25][26][27] In this study, we fabricated a bilayer film of Sb 2 Se 3 and VO 2 on a sapphire substrate, forming a heterojunction photodetector. Despite its simple structure, the photodetector shows a superhigh responsivity of 0.244 A W −1 without any outer bias and fast response speeds of 200 µs for rise and 360 µs for decay. It should be emphasized that our self-powered photodetectors possess both high responsivity and fast response speed simultaneously. Great prospect for commercial applications can be imagined on this bilayer device.