A simple and high-performance cellulose nanocrystal based biocatalytic Pickering emulsion system for pharmaceutical molecule vitamin E nicotinate.

The use of Pickering emulsions for biocatalysis is gaining increased attention. However, the extensive application is greatly limited due to the enzyme inactivation. Herein, a biocatalytic Pickering emulsion with high-performance utilizing cellulose nanocrystals immobilized lipases (CNCs-Lps) particles as stabilizer is advanced and applied for the synthesis of Vitamin E nicotinate. CNCs-Lps display high activity and reusability due to the construction of biocatalytic microreactor in the O/W emulsion system. The yield of vitamin E nicotinate ester reached up to 83 %. More importantly, the CNCs-Lps can be reused due to the similar principles to microreactors in Pickering emulsions. Reusability test showed that the CNCs-Lps could be recovered from the emulsion system by centrifugation and the yield of vitamin E nicotinate retains 78 % of initial value after five cycles, demonstrating overwhelming advantage than the fair counterpart with free lipases.

Laser maskless fast patterning for multitype microsupercapacitors.

Downsizing electrode architectures have significant potential for microscale energy storage devices. Asymmetric micro-supercapacitors play an essential role in various applications due to their high voltage window and energy density. However, efficient production and sophisticated miniaturization of asymmetric micro-supercapacitors remains challenging. Here, we develop a maskless ultrafast fabrication of multitype micron-sized (10 × 10 µm2) micro-supercapacitors via temporally and spatially shaped femtosecond laser. MXene/1T-MoS2 can be integrated with laser-induced MXene-derived TiO2 and 1T-MoS2-derived MoO3 to generate over 6,000 symmetric micro-supercapacitors or 3,000 asymmetric micro-supercapacitors with high-resolution (200 nm) per minute. The asymmetric micro-supercapacitors can be integrated with other micro devices, thanks to the ultrahigh specific capacitance (220 mF cm-2 and 1101 F cm-3), voltage windows in series (52 V), energy density (0.495 Wh cm-3) and power density (28 kW cm-3). Our approach enables the industrial manufacturing of multitype micro-supercapacitors and improves the feasibility and flexibility of micro-supercapacitors in practical applications.

Femtosecond Laser-Induced Anisotropic Structure and Nonlinear Optical Response of Yttria-Stabilized Zirconia Single Crystals with Different Planes.

Nonlinear optical properties have been extensively studied due to their promising nonlinear effects and various applications. With ultrashort duration and ultrahigh intensity, a femtosecond laser can fabricate various superior-quality micro-/nanostructures to improve the nonlinearity of materials, which are promising for stable and high-performance nonlinear devices. In this contribution, yttria-stabilized zirconia (YSZ) with fs laser-induced micro-/nanostructures is demonstrated to exhibit unique anisotropic light-material interaction and nonlinear optical response on [100], [110], and [111] planes. Time-resolved reflectivity of YSZ after fs laser excitation is investigated by a pump-probe experiment, which is consistent with simulations through the plasma model combined with a two-temperature model. These results indicate two early ablation mechanisms: Coulomb explosion and melting. Anisotropic crack structures are formed due to thermal stress, which is always ignored in fs laser fabrication and is verified by Raman mapping and analysis of slip systems on different crystal planes. Through the z-scan measurement, the nonlinear absorption (NLA) of crack structures is effectively improved, and a nearly 18 times enhancement of the NLA coefficient is acquired in [100] samples, while a 2 times enhancement in [110] and [111] samples. Such great enhancement of NLA is mainly due to the abundant presence of crack structures and the increase of fs laser-induced oxygen vacancies in [100] YSZ. These results provide a potential way of utilizing fs laser to improve the nonlinearity for the technological development in nonlinear devices.