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Triple-negative breast cancer (TNBC) is known for its strong invasiveness, high recurrence rates, and poor prognosis. Heme oxygenase-1 (HO-1) is closely related to tumor invasion, metastasis, recurrence and formation of tumor immunosuppression. The expression of HO-1 is high in TNBC and low in normal tissues. In this study, AgPPIX was synthesized as a heme oxygenase-1 (HO-1) inhibitor and a photosensitizer for TNBC therapy. PDA nanoparticles were synthesized and modified with anti-CD24 and p -toluenesulfonamide (PTSC) on their both sides to obtain PTSC@AgPPIX/PDA@anti-CD24 Janus nanoparticles (PAPC) for AgPPIX-targeted delivery. Anti-CD24 is targeted to CD24 on tumor cells and the PTSC moiety is targeted to endoplasmic reticulum (ER), where HO-1 is located. The results indicated that PAPC Janus nanoparticles exhibited higher cytotoxicity in 4T1 cells than that of the mono-modified nanoparticles. PAPC not only inhibited the expression of HO-1 and VEGF but also reduced TrxR activity significantly. Furthermore, PAPC not only promoted intracellular ROS production under laser irradiation for tumor photodynamic therapy (PDT) but also polarized TAMs from M2-type to M1 for tumor immunotherapy. In vivo experiments confirmed that PAPC could remodel the tumor immune microenvironment and almost completely inhibit the tumor growth in mouse models. Therefore, PAPC Janus nanoparticles are a promising nanoplatform with a dual-targeting capacity for TNBC immune/PDT synergistic therapy.

Inspired by the experimental realization of lattice-porous graphene and mesoporous MXenes, the possibility of lattice-penetrated porous titanium nitride, Ti 12 N 8 , was proposed and verified by density functional theory calculations. Stabilities, together with mechanical and electronic characteristics, are investigated and systemically discussed: both pristine and terminated (-O, -F, -OH) Ti 12 N 8 show great thermodynamic and kinetic stabilities; the reduced stiffness introduced by lattice pores makes Ti 12 N 8 better candidates for functional heterojunctions with less lattice mismatch. Subnanometer-sized pores increased the number of potential catalytic adsorption sites, and terminations allowed the band gap of MXene to reach 2.25 eV. Moreover, by changing terminations and introducing lattice channels, Ti 12 N 8 could be expected to be used for different applications: direct photocatalytic water splitting, excellent H 2 /CH 4 and He/CH 4 selectivity and admirable HER/CO 2 RR overpotentials. Such excellent characteristics could provide another possible path for flexible nanodevices with tunable mechanics, electronics and optoelectronics properties.

Mixing-induced nanoprecipitation (MINP) is an efficient, controllable, scalable, versatile, and cost-effective technique for the preparation of nanoparticles. In addition to the formulation of drugs, MINP has attracted tremendous interest in other fields. In this review, we highlight recent advances in the preparation of nanoparticles with complex nanostructures via MINP and their emerging applications beyond biomedicine. First, the mechanisms of nanoprecipitation and four mixing approaches for MINP are briefly discussed. Next, three strategies for the preparation of nanoparticles with complex nanostructures including sequential nanoprecipitation, controlling phase separation, and incorporating inorganic nanoparticles, are summarized. Then, emerging applications including the engineering of catalytic nanomaterials, environmentally friendly photovoltaic inks, colloidal surfactants for the preparation of Pickering emulsions, and green templates for the synthesis of nanomaterials, are reviewed. Furthermore, we discuss the structure-function relationships to gain more insight into design principles for the development of functional nanoparticles via MINP. Finally, the remaining issues and future applications are discussed. This review will stimulate the development of nanoparticles with complex nanostructures and their broader applications beyond biomedicine.

Due to the perfection of the nanofabrication in nanotechnology and nanoscience, ice lithography (IL) by patterning ice thin-films with a focused electron beam, as a significant derivative technology of electron beam lithography (EBL), is attracting growing attention, evoked by its advantages over traditional EBL with respects of in situ -fabrication, high efficiency, high accuracy, limited proximity effect, three-dimensional (3D) profiling capability, etc . However, theoretical modeling of ice lithography for replicated profiles on the ice resist (amorphous solid water, ASW) has rarely been reported so far. As the result, the development of ice lithography still stays at the experimental stage. The shortage of modeling methods limits our insight into the ice lithography capability, as well as theoretical anticipations for future developments of this emerging technique. In this work, an e-beam induced etching ice model based on the Monte Carlo algorithm for point/line spread functions is established to calculate the replicated profiles of the resist by ice lithography. To testify the fidelity of the modeling method, systematic simulations of the ice lithography property under the processing parameters of the resist thickness, electron accelerating voltage and actual patterns are performed. Theoretical comparisons between the IL on ASW and the conventional EBL on polymethyl methacrylate (PMMA) show superior properties of IL over EBL in terms of the minimum feature size, the highest aspect ratio, 3D nanostructure/devices, etc . The success in developing a modeling method for ice lithography, as reported in this paper, offers a powerful tool in characterizing ice lithography up to the theoretical level and down to molecular scales.

Two-dimensional transition metal dichalcogenides (TMDCs) are considered strong competitors for next generation semiconductor materials. In this paper, we propose direct electron-beam patterning of monolayer MoS2 inspired by an emerging ice lithography technique. Compared to conventional resist-based nanofabrication, ice-assisted patterning is free of contaminations from polymer resist and allows in situ processing of MoS2. The effects of electron beam dose and energy are investigated and nanoribbons with width below 30 nm are attainable. This method is expected to be applicable also to other TMDCs, providing a promising alternative for nanofabrication of 2D material devices.

Exploring highly active and durable Earth-abundant electrocatalysts to replace the precious noble metals holds great promise for the hydrogen evolution reaction (HER) from water splitting. Herein, a novel (110) high-index faceted binary-metal selenide (FeNiSe) nanosheet array grown on electrochemically exfoliated graphene foil (FeNiSe-NS/EG) is developed from its vertically-oriented NiFe-LDH nanosheet/EG precursor through a low-temperature selenization reaction. Benefiting from its unique 3D configuration and enhanced electrical conductivity, the obtained FeNiSe-NS/EG electrode exhibits excellent electrocatalytic activity toward the HER with small overpotentials of -187 and -222 mV at current densities of 10 and 20 mA cm-2, a low Tafel slope of 65 mV dec-1, and remarkable long term stability in alkaline media, outperforming the recently reported NiFe-based non-precious metal HER catalysts. Theoretical calculations and experimental results reveal that the synergistic effects of the exposed (110) high-index facets and Fe dopants give rise to a greatly enhanced HER performance.

The ability to continuously tune the emission wavelength of mid-infrared thermal emitters while maintaining high peak emissivity remains a challenge. By incorporating the nonvolatile phase changing material Ge 2 Sb 2 Te 5 (GST), two different kinds of wavelength-tunable mid-infrared thermal emitters based on simple layered structures (GST-Al bilayer and Cr-GST-Au trilayer) are demonstrated. Aiming at high peak emissivity at a tunable wavelength, an Al film and an ultrathin (∼5 nm) top Cr film are adopted for these two structures, respectively. The gradual phase transition of GST provides a tunable peak wavelength between 7 μm and 13 μm while high peak emissivity (>0.75 and >0.63 for the GST-Al and Cr-GST-Au emitters, respectively) is maintained. This study shows the capability of controlling the thermal emission wavelength, the application of which may be extended to gas sensors, infrared imaging, solar thermophotovoltaics, and radiative coolers.

Here we report a new kind of three-dimensional (3D) hybrid aerogels, based on graphene oxide (GO) and black phosphorus nanoflakes (BPNFs), for the first time. Our results demonstrate that the as-prepared GO/BPNF hybrid aerogels exhibited significantly enhanced photothermal as well as electrical properties of GO aerogels due to the addition of BP. Moreover, they also possessed excellent photothermal stability under ambient conditions without any protection, which can be ascribed to the coverage of BPNFs with GO nanosheets in these aerogels. This exceptional photothermal property along with robust stability renders GO/BPNF aerogels with promising bio-related applications, such as photothermal therapy for cancer treatment.

In this study, we report a promising rGO-CNT hybrid nanofiltration (NF) membrane that was fabricated by loading reduced graphene oxide that was intercalated with carbon nanotubes (rGO-CNTs) onto an anodic aluminum oxide (AAO) microfiltration membrane via a facile vacuum-assisted filtration process. To create this NF membrane, the CNTs were first dispersed using block copolymers (BCPs); the effects of the types and contents of BCPs used on the dispersion of CNTs have been investigated. The as-prepared rGO-CNT hybrid NF membranes were then used for drinking water purification to retain the nanoparticles, dyes, proteins, organophosphates, sugars, and particularly humic acid. Experimentally, it is shown that the rGO-CNT hybrid NF membranes have high retention efficiency, good permeability and good anti-fouling properties. The retention was above 97.3% even for methyl orange (327 Da); for other objects, the retention was above 99%. The membrane's permeability was found to be as high as 20-30 L m(-2) h(-1) bar(-1). Based on these results, we can conclude that (i) the use of BCPs as a surfactant can enhance steric repulsion and thus disperse CNTs effectively; (ii) placing well-dispersed 1D CNTs within 2D graphene sheets allows an uniform network to form, which can provide many mass transfer channels through the continuous 3D nanostructure, resulting in the high permeability and separation performance of the rGO-CNT hybrid NF membranes.

The study of all-dielectric nanoantennas has become an emerging branch of the study of optical nanoantennas in recent years, with all-dielectric nanoantennas having an outstanding ability to tailor forward and backward unidirectional scattering arising from interference mainly between electric dipoles and magnetic dipoles induced simultaneously inside a nanoparticle. To further control their radiation properties, we demonstrate the off-normal scattering, by a silicon stair-like nanoantenna, of an incident near-infrared plane wave due to multipolar interference. The radiation angle could be tailored over a 20-degree range by tuning the geometric parameters of the nanoantenna. A multipolar model was adopted to interpret the interference among one electric dipole, two magnetic dipoles and one electric quadrupole induced inside the nanoantenna. The maximum radiation angle reached 20° at a wavelength near 1550 nm. Such a stair-like nanoantenna sets a good example for further flexible manipulation of multipolar resonances inside all-dielectric nanoparticles, which is an essential step towards practical application of all-dielectric nanoantennas in the near future.

Ordered mesoporous MnCo2O4 nanomaterials were successfully prepared through the nanocasting route using SBA-15 and KIT-6 as hard templates. These mesoporous nanomaterials were characterized using XRD, BET, TEM, NH3-TPD, H2-TPR, NO-TPD, XPS and DRIFT. The low temperature selective catalytic reduction (SCR) activity of NO with NH3 was investigated, which revealed that 3D-MnCo2O4 using KIT-6 as a template can totally clean all NO over a wide temperature range of 100-250 °C with a gas hourly space velocity (GHSV) of 32,000 h(-1), while 2D-MnCo2O4 with SBA-15 as a template had 95% conversion rate at the same condition. 3D-MnCo2O4 showed the best performance to clean NO due to its typical three-dimensional porous structure, large specific surface area, abundant active surface oxygen species and Lewis acid sites. All the results indicate that a novel, cheap catalyst for catalytic removal of NO can be designed by controlling the morphology at the nanoscale.

Recently, the control of anomalous light bending via flat gradient-phase metasurfaces has enabled many unprecedented applications. However, either low manipulation efficiency or challenging difficulties in fabrication hinders their practical applications, in particular in the visible range. Therefore, a concept of degenerated image dipole array is reported to realize anomalous light bending with high efficiency. A continuous phase delay varying rather than a discrete one, along with an in-plane wave vector is utilized to achieve anomalous light bending, by controlling and manipulating the mutual coupling between dipole array and the dipole array of its image. The anomalous light bending covers almost the entire visible range with broad incident angles, accompanied with preserved well-defined planar wavefront. In addition, this design is feasible to be fabricated with recent nanofabrication techniques due to its planarized surface configuration. The concept of imperfect image dipole array degenerated from ideal metamaterial absorbers surprisingly empowers significant enhancement in light manipulation efficiency for visible light in a distinct fashion.

Light-induced rapid annealing (LIRA) is a widely used method to modify the morphology and crystallinity of noble metal nanoparticles, and the nanoparticles generally evolve into nanospheres. It is rather challenging to form faceted Au nanocrystals on a substrate using LIRA. Here the formation of spatially ordered Au nanocrystals using a continuous wave infrared laser is reported, assisted by a metamaterial perfect absorber. Faceted Au nanocrystals in truncated-octahedral or multi-twinned geometries can be obtained. The evolution of morphology and crystallinity of the Au nanoparticles during laser annealing is also revealed, where the crystal grain growth and the surface melting are shown to play key roles in nanocrystal formation. The evolution of morphology also gives the freedom of tuning the absorption spectrum of the metamaterial absorber. These findings provide a novel way for tailoring the morphology and crystallinity of metallic nanoparticles and may pave the way to fabricate refined nano-devices in many potential applications for optics, electronics, catalysis, surface-chemistry and biology.

We propose a counter-intuitive mechanism of constructing an ultrathin broadband transparent device with two perfect blackbodies. By introducing hybridization of plasmon modes, resonant modes with different symmetries coexist in this system. A broadband transmission spectrum in the near infrared regime is achieved through controlling their coupling strengths, which is governed by the thickness of high refractive index layer. Meanwhile, the transparency bandwidth is found to be tunable in a large range by varying the geometric dimension. More significantly, from the point view of applications, the proposed method of achieving broadband transparency can perfectly tolerate the misalignment and asymmetry of periodic nanoparticles on the top and bottom, which is empowered by the unique dual of coupling-in and coupling-out processes within the pair of blackbodies. Moreover, roughness has little influence on its transmission performance. According to the coupled mode theory, the distinguished transmittance performance is physically interpreted by the radiative decay rate of the entire system. In addition to the feature of uniquely robust broadband transparency, such a ultrathin seamless nanostructure (in the presence of a uniform silver layer) also provides polarization-independent and angle-independent operations. Therefore, it may power up a wide spectrum of exciting applications in thin film protection, touch screen techniques, absorber-emitter transformation, etc.