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Cathodes must accommodate the excellent performance of the applied anodes in lithium batteries. Li-rich Mn-based cathode materials with a specific capacity beyond 250 mAh·g−1 are considered some of the most promising cathode materials, although they suffer from some unsolved problems. In this paper, a series of Li1.2Ni0.2Mn0.6-xAlxO2 cathodes with an in situ-synthesized Li2CO3 coating layer by a one-step method is utilized to enhance their electrochemical performance by inhibiting the transition from a layered structure to a spinel structure and reducing the generation of Mn3+. The Li1.2Ni0.2Mn0.56Al0.04O2@Li2CO3 coating sample exhibits an excellent capacity retention rate of 89.5% and a small voltage decay of 1.11 mV per cycle after 200 cycles at 1 C. Lithium-ion full cells composed of Li1.2Ni0.2Mn0.56Al0.04O2@Li2CO3 and graphite show an energy density of 443.7 Wh·kg−1 at 0.1 C, and the capacity retention rate is 95.6% after 200 cycles at 1 C. These results offer prospects for satisfying the high energy density requirements of electric equipment. [ABSTRACT FROM AUTHOR]

A diode-pumped Nd:YVO4 laser passively Q switched by a semiconductor absorber is demonstrated. The Q-switched operation of the laser has an average output power of 135 mW with a 1.6 W incident pump power. The minimum pulse width is measured to be about 8.3 ns with a repetition rate of 2 MHz. To our knowledge, this is the first demonstration of a solid-state laser passively Q-switched by such a composite semiconductor absorber. OCIS codes: 140.3580, 140.3540, 140.3480.

We have demonstrated stable self-starting passive mode locking in a diode-end-pumped Nd:[Gd.sub.0.5]-[Y.sub.0.5]V[O.sub.4] laser by using an [In.sub.0.25][Ga.sub.0.75]As absorber grown at low temperature (LT [In.sub.0.25][Ga.sub.0.75]As absorber). An [In.sub.0.25][Gao.sub.0.75] As single-quantum-well absorber, which was grown directly on the GaAs buffer by use of the metal-organic chemical-vapor deposition technique, acts simultaneously as a passive mode-locking device and as an output coupler. Continuous-wave mode-locked pulses were obtained at 1063.5 nm. We achieved a pulse duration of 2.6 ps and an average output power of 2.15 W at a repetition rate of 96.4 MHz. OCIS codes: 140.4050, 140.3530, 140.3480, 160.6000, 140.3380.

Strategies that enable simultaneous morphology‐tuning and electroreduction performance boosting are much desired for the exploration of covalent organic frameworks in efficient CO2 electroreduction. Herein, a kind of functionalizing exfoliation agent has been selected to simultaneously modify and exfoliate bulk COFs into functional nanosheets and investigate their CO2 electroreduction performance. The obtained nanosheets (Cu−Tph−COF−Dct) with large‐scale (≈1.0 μm) and ultrathin (≈3.8 nm) morphology enable a superior FECH4 (≈80 %) (almost doubly enhanced than bare COF) with large current‐density (−220.0 mA cm−2) at −0.9 V. The boosted performance can be ascribed to the immobilized functionalizing exfoliation agent (Dct groups) with integrated amino and triazine groups that strengthen CO2 absorption/activation, stabilize intermediates and enrich the CO concentration around the Cu active sites as revealed by DFT calculations. The point‐to‐point functionalization strategy for modularly assembling Dct‐functionalized COF catalyst for CO2 electroreduction will open up the attractive possibility of developing COFs as efficient CO2RR electrocatalysts. [ABSTRACT FROM AUTHOR]