Regulation of the atom-atom interspaces of dual-atom catalysts is essential to optimize the dual-atom synergy to achieve high activity but remains challenging. Herein, we report an effective strategy to regulate the Pt 1 -Ni 1 interspace to achieve Pt 1 Ni 1 dimers and Pt 1 + Ni 1 heteronuclear dual-single-atom catalysts (HDSACs) by tailoring steric hindrance between metal precursors during synthesis. Spectroscopic characterization reveals obvious electron transfers in Pt 1 Ni 1 oxo dimers but not in Pt 1 + Ni 1 HDSAC. In the hydrolysis of ammonia borane (AB), the H 2 formation rates show an inverse proportion to the Pt 1 -Ni 1 interspace. The rate of Pt 1 Ni 1 dimers is � 13 and 2 times higher than those of Pt 1 and Pt 1 + Ni 1 HDSAC, manifesting the interspace-dependent synergy. Theoretical calculations reveal that the bridging OH group in Pt 1 Ni 1 dimers promotes water dissociation, while Pt 1 facilitates the cleavage of BÀ H bonds in AB, which boosts a bifunctional synergy to accelerate H 2 production cooperatively.

Intricate hollow carbon structures possess vital function for anchoring polysulfides and enhancing the utilization of sulfur in room-temperature sodium–sulfur batteries. However, their synthesis is extremely challenging due to the complex structure. Here, a facile and efficient strategy is developed for the controllable synthesis of N/O-doped multichambered carbon nanoboxes (MCCBs) by selective etching and stepwise carbonization of ZIF-8 nanocubes. The MCCBs consist of porous carbon shells on the outside and connected carbon grids with a hollow structure on the inside, bringing about a MCCBs structure. As a sulfur host, the multichambered structure has better spatial encapsulation and integrated conductivity via the inner interconnected carbon grids, which combines the characteristics of short charge transfer path and superb physicochemical adsorption along with mechanical strength. As expected, the S@MCCBs cathode realizes decent cycle stability (0.045% capacity decay per cycle over 800 cycles at 5 A g–1) and enhanced rate performance (328 mA h g–1 at 10 A g–1). Furthermore, in situ transmission electron microscopy (TEM) observation confirms the good structural stability of the S@MCCBs during the (de)­sodiation process. Our work demonstrates an effective strategy for the rational design and accurate construction of intricate hollow materials for high-performance energy storage systems.

The catalytic conversion of biomass-derived furfural (FFA) into cyclopentanone (CPO) in aqueous solution is an important pathway to obtain sustainable resources. However, the conversion and selectivity under mild conditions are still unsatisfactory. In this study, a catalyst consisting of NiÀ NiO heterojunction supported on TiO 2 with optimized composition of anatase and rutile (NiÀ NiO/TiO 2-Re450) is prepared by pyrolysis at 450°C. With NiÀ NiO/TiO 2-Re450, as catalyst, complete conversion of FFA and 87.4 % yield of CPO are achieved under mild reaction conditions (1 MPa, 140°C, 6 h). 95.4 % FFA conversion is retained up to the fifth run, indicating the high stability of the catalyst. Multiple characterizations, control experiments, and theoretical calculations demonstrate that the good catalytic performance of NiÀ NiO/TiO 2-Re450 can be attributed to a synergistic effect of the NiÀ NiO heterojunction and the TiO 2 support. This low-cost catalyst may expedite the catalytic upgrading and practical application of biomass-derived chemicals.

The hydrolysis of ammonia borane (NH 3 BH 3 or AB) at room temperature is a promising method to produce hydrogen, but the complete reaction mechanism is still less investigated. Herein, the full hydrolysis process of the AB molecule on single Pt atom coordinated by two carbon atoms and one nitrogen atom (Pt 1 −C 2 N 1 ) on nitrogen doped graphene is investigated using the density functional theory (DFT) method. Our results demonstrate that the rate-limiting step is the formation of *BH 2 NH 3 by breaking the first B−H bond in AB with an energy barrier of 0.68 eV, implying that Pt 1 −C 2 N 1 is a potential room-temperature catalyst for the full hydrolysis of AB. In addition, 27 more types of M 1 −C 2 N 1 (M represents transiton metal atom) and Pt 1 supported on nitrogen-doped graphene with different local coordination environments (Pt 1 −C x N y , x and y are the number of carbon and nitrogen atoms that coordinated with the platinum atom) are considered to screen out potential single-atom catalysts for AB hydrolysis. The screening results further show that Pt 1 −C 1 N 2 is another potential catalyst for AB hydrolysis. In particular, two hydrogen atoms precovered on Pt 1 −C 1 N 2 , resulting in a lower energy barrier for the rate-limiting step than that on Pt 1 −C 2 N 1 . This study provides a prototype of Pt 1 −C 1 N 2 and Pt 1 −C 2 N 1 for catalytic full hydrolysis of AB at room temperature.