Catalytic combination: By combining the advantages of organocatalysts and ionic liquids, a functionalized chiral ionic liquid such as 1 can act as a highly efficient and reusable organocatalyst for the asymmetric Michael addition reaction of ketones and aldehydes with nitroalkenes.

Visible light communications (VLC) is an alternative method of indoor wireless communications that requires sensitive receivers. Ideally, single photon avalanche detectors (S PADs) could be used to create more sensitive receivers. However, the dead-time, finite output pulse width and photon detection efficiency of existing S PAD arrays limits their sensitivity and bandwidth. In this paper an accurate equation for the impact of dead-time on the sensitivity of a S PAD array is presented. In addition the impact of the width of the output pulses on the on-off keying (OOK) data rate is investigated. Finally, a comparison between receivers containing an APD and a large array of S PADs shows that although the receiver containing the S PAD is more sensitive in the dark the APD-based receiver is more sensitive in normal operating condition. However, the models that predict the performance of both receivers suggest that newer S PAD arrays will enable significant improvements in receiver sensitivity.

Heterogeneous single-atom catalysts involve isolated metal atoms anchored to a support, displaying high catalytic performance and stability in many important chemical reactions. We present a general theoretical framework to establish the thermodynamic stability of metal single atoms and metal nanoparticles on a support in the presence of adsorbates. As a case study, we establish for Pt−CeO 2 the CO partial pressure and temperature range within which Pt single atoms are more stable than Pt nanoparticles. Density functional theory and kinetic Monte Carlo simulations demonstrate that Pt atoms doped into the CeO 2 surface exhibit a very high CO oxidation activity and thermodynamic stability in comparison to models involving Pt single atoms on terraces and steps of CeO 2 . An intermediate CO adsorption strength is important to explain a high activity. Our work provides a systematic strategy to evaluate the stability and reactivity of single atoms on a support.

A simple bioinspired ortho-quinone catalyst for the aerobic oxidative dehydrogenation of amines to imines is reported. Without any metal cocatalysts, the identified optimal ortho-quinone catalyst enables the oxidations of α-branched primary amines and cyclic secondary amines. Mechanistic studies have disclosed the origins of different performances of ortho-quinone vs para-quinone in biomimetic amine oxidations.