This review summarizes the recent progress in preparations, functionalities and applications of composites of metal–organic frameworks (MOFs) and carbon-based materials.

CO₂ adsorption and methanation on a Ni/Ce_0.5Zr_0.5O₂ catalyst has been investigated using in situ FTIR spectroscopy. CO₂ adsorption and methanation experiments were conducted on both components of the support and the catalyst to identify the adsorption species and any intermediate species. It was proposed that CO₂ prefers to adsorb on surface oxygen sites adjacent to Ce(III) compared with those adjacent to Ce(IV)/Zr or surface hydroxyl sites. Five adsorption species were revealed for CO₂ adsorption on Ni/Ce_0.5Zr_0.5O₂ and monodentate carbonates formed on Ce(III) are easier to be hydrogenated than those on Ce(IV). Formate species were found to be the main intermediate species during the reaction and Ce(III) sites were proposed to be active sites for their hydrogenation. The adsorption and hydrogenation of formic acid were also conducted to confirm the identification of the intermediate species during the reaction. –CH₂OH species were detected for the first time and found to be the further intermediates in the reaction.

A WO₃/CeO₂-ZrO₂ catalyst system was discovered for selective catalytic reduction of NO_x with NH₃; the catalyst (10 wt% WO₃ loading) showed nearly 100% NO_x conversion in a temperature range of 200–500 °C, at a space velocity of 90 000 h⁻¹ in a simulated diesel exhaust containing 550 ppm NO_x (NO : NO₂ feed ratio at 1.0), 10 vol% H₂O and 10 vol% CO₂; the catalyst also exhibited high temperature stability.

Acceleration measurement is of great significance due to its extensive applications in military/industrial fields. In recent years, scientists have been pursuing methods to improve the performance of accelerometers, particularly through seeking new sensing mechanisms. Herein, we present a synchronized oscillator-based enhancement approach to realize a fivefold resolution improvement of a microelectromechanical resonant accelerometer. Through the unidirectional electrical coupling method, we achieved synchronization of the sensing oscillator of the microelectromechanical resonant accelerometer and an external reading oscillator, which remarkably enhanced the stability of the oscillation system to 19.4 ppb and the resolution of the accelerometer to 1.91 μg. In addition, the narrow synchronization bandwidth of conventional synchronized oscillators was discussed, and hence, we propose a novel frequency automatic tracking system to expand the synchronization bandwidth from 113 to 1246 Hz, which covers the full acceleration measurement range of ±1 g. For the first time, we utilized a unidirectional electrical synchronization mechanism to improve the resolution of resonant sensors. Our comprehensive scheme provides a general and powerful solution for performance enhancement of any microelectromechanical system (MEMS) resonant sensor, thereby enabling a wide spectrum of applications.