halide perovskites (LDHPs), the optically active inorganic blocks are separated and surrounded by insulating organic components with intrinsic quantum confinement effects, which readily leads to firmly confined bound excitons in the metal halide species under photo excitation. Simultaneously, the strong electronquantum coupling transiently localizes the excitons along with excited-state structural deformation, which produces selftrapped excitons (STE) with lower excited state energy. [4] Therefore, the bulk LDHPs always display strongly Stokes-shifted broadband light emissions, which are different from the narrow emission bands of 3D halide perovskites. [5] These distinctive luminescent performances endow LDHPs with a series of unique applications complementary to the 3D perovskites in solid-state lighting, X-ray scintillation, remote thermometry, and thermography, especially for white light emitting diodes (WLEDs). [6] Among all the PL qualities, PL quantum yield (PLQY) is one of the most important indicators for optoelectronic applications of hybrid halide perovskites. To achieve higher PLQY and more desirable luminescence performance, substantial optically active centers based on ns 2 electronic configuration of valence shell have been explored including Sn 2+ , Ge 2+ , Pb 2+ , Bi 3+ , and Sb 3+ . [7][8][9] In these fascinating hybrid metal halides, the 5s 2 metal halides readily occupy the maximum of emission efficiency owing to the unique expressed structural distortion level induced by the out shell lone pair. [10] Simultaneously considering the instabilities of Sn 2+ and Ge 2+ halides, toxicity of Pb 2+ , metal as well as low efficiencies of Bi 3+ phases, green 5s 2 Sb 3+ based hybrid metal halides are deemed to be one of most promising ultrabroadband luminescent materials with higher PLQYs and oxidation resistance abilities. [7b,8a,11] Up to now, the PLQYs of 0D hybrid antimony halides based on discrete [SbX 5 ] 2− and [SbX 6 ] 3− units can reach up to near unity due to strong quantum confinement effect. [12] These outstanding PL properties intrigued further in-depth understanding the enhancement or modulating mechanism of PLQY for hybrid antimony halides from molecular design level, which is also greatly desirable for subsequent rational design of new high-performance hybrid halides. Rationally optimizing the photoluminescence performance via accurate structural modulation is one of most important and challenging issues for hybrid halides. Herein, a viable crystal dimensional reduction strategy is proposed to reasonably enhance the photoluminescence quantum yield (PLQY) of hybrid antimony halide. Specifically, a synthetic technique is developed and new 1D [DMPZ]SbCl 5 • H 2 O (DP-SbCl 5 ) is sliced to 0D [DMPZ] 2 SbCl 6 • Cl • (H 2 O) 2 (DP-SbCl 6 ) with crystal dimensional reduction from infinite [SbCl 5 ] 2− chain to discrete [SbCl 6 ] 3− octahedron. Comparing with nonluminescent 1D DP-SbCl 5 , 0D DP-SbCl 6 displays highly efficient broadband yellow light emission with enhanced PLQY up to 75.94%. ...

Facile, green and economical preparation technique is critical for the cost-effective scale-up manufacture and optoelectronic device engineering of halide perovskites. Herein, we developed a viable solvent-free mechanochemical synthetic route to...

Cellulase has many potential applications in ethanol production, extraction of medicinal ingredients, food, brewing, oil exploration, environmental protection. However, the widespread use of cellulase is limited by its relatively high production costs and low biological activity. Therefore, we studied the enzymatic properties and reusability of cellulase immobilized on multiwalled carbon nanotubes and sodium alginate for the first time. The results showed that the optimum temperature and pH of immobilized cellulase was 40 °C and 3.0, respectively. After 1 month of storage at 4 °C, the enzyme activity of immobilized cellulase dropped to 71.2% of the baseline. Immobilized cellulase was proved to be reusable and maintained ~ 70% of its activity after 7 cycles of repeated use. Versus free cellulase, the immobilized cellulase showed good thermal stability, pH resistance, storage stability and reusability, which could be beneficial in large-scale industrial manufacturing processes.

Considering low photoluminescence quantum yield (PLQY < 5%) of blue emissive CsPbCl3 bulk crystal and the high toxicity of Pb2+, it is significant to explore new single crystalline lead-free perovskites with highly efficient blue light emission. Herein, two new zero-dimensional (0D) hybrid indium halides of [H2EP]2InCl6·Cl·H2O·C3H6O and [H3AEP]­InCl6··H2O (EP = 1-ethylpiperazine, AEP = N-aminoethyl piperazine) were prepared. Remarkably, these 0D indium halides display unusual blue light emissions (about 430 nm) with a highest PLQY of 13.44%. To the best of our knowledge, this work represents one of the first higher energy blue light emitters in hybrid indium perovskites, which would advance the research on lead-free hybrid halides for next-generation luminescent materials.

Intelligent stimuli-responsive fluorescence materials are extremely pivotal for fabricating luminescent turn-on switching in solid-state photonic integration technology, but it remains a challenging objective for typical 3-dimensional (3D) perovskite nanocrystals. Herein, by fine-tuning the accumulation modes of metal halide components to dynamically control the carrier characteristics, a novel triple-mode photoluminescence (PL) switching was realized in 0D metal halide through stepwise single-crystal to single-crystal (SC-SC) transformation. Specifically, a family of 0D hybrid antimony halides was designed to exhibit three distinct types of PL performance including nonluminescent [Ph 3 EtP] 2 Sb 2 Cl 8 ( 1 ), yellow-emissive [Ph 3 EtP] 2 SbCl 5 ·EtOH ( 2 ), and red-emissive [Ph 3 EtP] 2 SbCl 5 ( 3 ). Upon stimulus of ethanol, 1 was successfully converted to 2 through SC-SC transformation with enhanced PL quantum yield from ~0% to 91.50% acting as “turn-on” luminescent switching. Meanwhile, reversible SC-SC and luminescence transformation between 2 and 3 can be also achieved in the ethanol impregnation–heating process as luminescence vapochromism switching. As a consequence, a new triple-model turn-on and color-adjustable luminescent switching of off–on I –on II was realized in 0D hybrid halides. Simultaneously, wide advanced applications were also achieved in anti-counterfeiting, information security, and optical logic gates. This novel photon engineering strategy is expected to deepen the understanding of dynamic PL switching mechanism and guide development of new smart luminescence materials in cutting-edge optical switchable device.

By using a simple room temperature solution reaction, we prepared a new type of one-dimensional (1D) hybrid lead halide [DMEDA]PbCl4. The compound gives a bright yellow emission with efficient photoluminescence quantum efficiency (PLQE) and optical stability.

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