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Mesoporous carbon derived from pyrolysis of metal–organic frameworks (MOFs) is advantageous owing to its high specific surface area, large pore volume, and versatility in both structure and composition. Heteroatom doping on mesoporous carbon by synthesizing with heteroatom containing ligands (pre-synthetic process) or incorporating heteroatom-containing compounds during pyrolysis (post-doping) can further enhance its electrochemical properties. Although both methods have been applied to increase the doping content, the effects of the pre-synthetic process and post-doping have not yet been systematically studied. Herein, we have synthesized mesoporous carbon derived from sulfur-containing MOFs for the first time using 2,5-disulfanylterephthalic acid as a ligand and added dopants (melamine for N-doping and thiourea for N,S-codoping). We systematically compared the performance of mesoporous carbon as cathodes for the oxygen reduction reaction (ORR) and lithium–sulfur (Li–S) batteries with previous studies, which used terephthalic acid and its analogues as pre-synthetic ligands and various dopants as post-doping sources. Our work showed the synergetic effect of heteroatoms from dual-doping processespecially sulfur (S from pre-synthetic process and N,S from post-doping), which not only enhanced catalytic activity (limiting current density (J L) of −5.19 mA·cm–2), stability, and methanol tolerance as an ORR catalyst but also rendered superior stability of 85.2% over 100 cycles as a cathode of Li–S batteries.

Stimuli-responsive systems are attractive since their properties can be controlled by external stimuli and/or surrounding environment. Recently, more than one stimulus is utilized in order to enhance the performance of systems, or to bypass undesired effects. However, most of previous research on multi-stimuli has been focused on enhancing or inducing changes in one type of response. Herein, we developed a nanocomposite material with independent multi-states composed of photo-responsive polymer and quantum dots (QDs), in which its properties can independently be controlled by different wavelengths of light. More specifically, azobenzene-incorporated poly(dimethylsiloxane) (AzoPDMS) triggers photobending (PB) by 365 nm light and uniformly dispersed methylammonium lead bromide perovskite (MAPbBr 3 ) QDs show photoluminescence (PL) by light below 500 nm. The PB and PL could be simultaneously and independently controlled by the wavelength of applied light creating multi-states. Our approach is novel in that it creates multiple independent states which can further be used to transfer information such as logic gates (00 (2) , 01 (2) , 10 (2) , 11 (2) ) and possibly widen its application to flexible and transparent opto-electric devices.