Hierarchical assembly of hollow microstructures is of great scientific and practical value and remains a great challenge. This paper presents a facile and one‐pot synthesis of Cu2O microspheres with multilayered and porous shells, which were organized by nanocrystals. The time‐dependent experiments revealed a two‐step organization process, in which hollow microspheres of Cu2(OH)3NO3 were formed first due to the Ostwald ripening and then reduced by glutamic acid, the resultant Cu2O nanocrystals were deposited on the hollow intermediate microspheres and organized into finally multishell structures. The special microstructures actually recorded the evolution process of materials morphologies and microstructures in space and time scales, implying an intermediate‐templating route, which is important for understanding and fabricating complex architectures. The Cu2O microspheres obtained were used to fabricate a gas sensor, which showed much higher sensitivity than solid Cu2O microspheres.

A new process is optimized and presented for the recovery and regeneration of LiFePO4 from spent lithium-ion batteries (LIBs).

This study focused on synthesis and characterization of Ti 4 O 7 reactive electrochemical membranes (REMs) amended with powder-activated carbon (PAC) or multiwalled carbon nanotubes (MWCNTs). These composite REMs were evaluated for simultaneous adsorption and electrochemical reduction of N-nitrosodimethylamine (NDMA). The carbon-Ti 4 O 7 composite REMs had high electrical conductivities (1832 to 2991 S m −1 ), where carbon and Ti 4 O 7 were in direct electrical contact. Addition of carbonaceous materials increased the residence times of NDMA in the REMs by a factor of 3.8 to 5.4 and therefore allowed for significant electrochemical NDMA reduction. The treatment of synthetic solutions containing 10 μM NDMA achieved >4-log NDMA removal in a single pass (liquid residence time of 11 to 22 s) through the PAC-REM and MWCNT-REM with the application of a −1.1 V/SHE cathodic potential, with permeate concentrations between 18 and 80 ng L −1 . The treatment of a 6.7 nM NDMA-spiked surface water sample, under similar operating conditions (liquid residence time of 22 s), achieved 92 to 97% removal with permeate concentrations between 16 and 40 ng L −1 . Density functional theory calculations determined a probable reaction mechanism for NDMA reduction, where the rate-limiting step was a direct electron transfer reaction.

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