Here we report a new rhodamine-based fluorescent probe containing a selenium−nitrogen bond for detecting thiols based on the nucleophilic substitution of sulfhydryl. The probe was successfully applied to the imaging of thiols in both HL-7702 cells and HepG2 cells with high sensitivity and selectivity.

Ultrasmall Ni2P/rGO was synthesized using template-confinement strategy of MOFs and served as a highly efficient electrocatalyst for overall water splitting.

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A novel nanoporous metal−organic framework NPC-4 with excellent thermal stability was assembled from 2,3,5,6-tetramethylbenzene-1,4-diisophthalate (TMBDI) and the paddle-wheel secondary building unit (Cu 2 (COO) 4 ). The porous structure comprises a single type of nanoscale cage (16 Å diameter) interconnected by windows (5.2 × 6.3 Å), which give a high pore volume. CH 4 (195−290 K), CO 2 (198−303 K), N 2 (77 K), and H 2 (77 K) adsorption isotherms were studied for pressures up to 20 bar. NPC-4 exhibits excellent methane and carbon dioxide storage capacities on a volume basis with very high adsorbate densities, under ambient conditions. Isobars were investigated to establish the relationship for adsorption capacities over a range of storage temperatures. The isosteric enthalpies of adsorption for both CH 4 and CO 2 adsorption did not vary significantly with amount adsorbed and were ∼15 and ∼25 kJ mol −1 , respectively. The adsorption/desorption kinetics for CH 4 and CO 2 were investigated and activation energies, enthalpies of activation, and diffusion parameters determined using various kinetic models. The activation energies for adsorption obtained over a range of uptakes from the stretched exponential kinetic model were 5.1− 6.3 kJ mol −1 (2−13.5 mmol g −1 ) for CO 2 and 2.7−5.6 kJ mol −1 (2−9 mmol g −1 ) for CH 4 . The activation energies for surface barriers and diffusion along pores for both CH 4 and CO 2 adsorption obtained from a combined barrier resistance diffusion model did not vary markedly with amount adsorbed and were <9 kJ mol −1 . Comparison of kinetic and thermodynamic parameters for CH 4 and CO 2 indicates that a surface barrier is rate determining at high uptakes, while intraparticle diffusion involving diffusion through pores, consisting of narrow windows interconnecting with nanocages, being rate determining at very low uptakes. The faster CH 4 intraparticle adsorption kinetics compared with CO 2 for NPC-4 was attributed to faster surface diffusion due to the lower isosteric enthalpy of adsorption for CH 4 .