Unlocking single-atom catalysts via amorphous substrates

Single-atom catalysts(SACs)reveal great potential for application in catalysis due to their fully exposed active sites.In general,single atoms(SAs)and the coordination substrates need to have strong interactions or charge transfer to ensure the atomic dispersion,which requires the selection of a suitable substrate to stabilize the target atoms.Recent studies have demonstrated that amorphous materials with abundant defects and coordinatively unsaturated sites can be used as substrates for more efficient capturing SAs,further enhancing the catalytic performance.In this review,we discuss recent research progress of SAs loaded on amorphous substrates for enhanced catalytic activity.Firstly,we summarize the commonly used amorphous substrates for stabilizing SAs.Subsequently,we present several advanced applications of amorphous SACs in the field of catalysis,including electrocatalysis and photocatalysis.And then,we also clarify the synergistic mechanism between SAs and amorphous substrate on catalytic process.Finally,we summarize the challenges with our personal views and provide a critical outlook on how amorphous SACs continue to evolve.

Advance in 3D self-supported amorphous nanomaterials for energy storage and conversion

The advancement of next-generation energy technologies calls for rationally designed and fabricated electrode materials that have desirable structures and satisfactory performance.Three-dimensional(3D)self-supported amorphous nanomaterials have attracted great enthusiasm as the cornerstone for building high-performance nanodevices.In particular,tremendous efforts have been devoted to the design,fabrication,and evaluation of self-supported amorphous nanomaterials as electrodes for energy storage and conversion devices in the past decade.However,the electrochemical performance of devices assembled with 3D self-supported amorphous nanomaterials still remains to be dramatically promoted to satisfy the demands for more practical applications.In this review,we aim to outline the achievements made in recent years in the development of 3D self-supported amorphous nanomaterials for a broad range of energy storage and conversion processes.We firstly summarize different synthetic strategies employed to synthesize 3D nanomaterials and to tailor their composition,morphology,and structure.Then,the performance of these 3D self-supported amorphous nanomaterials in their corresponding energy-related reactions is highlighted.Finally,we draw out our comprehensive understanding towards both challenges and prospects of this promising field,where valuable guidance and inspiration will surely facilitate further development of 3D self-supported amorphous nanomaterials,thus enabling more highly efficient energy storage and conversion devices that play a key role in embracing a sustainable energy future.

Rational design of asymmetric atomic Ni-P1N3 active sites for promoting electrochemical CO_(2)reduction

The atomic-level interfacial regulation of single metal sites through heteroatom doping can significantly improve the characteristics of the catalyst and obtain surprising activity.Herein,nickel single-site catalysts(SSCs)with dual-coordinated phosphorus and nitrogen atoms were developed and confirmed(denoted as Ni-PxNy,x=1,2 and y=3,2).In CO_(2)reduction reaction(CO_(2)RR),the CO current density on Ni-PxNy was significantly higher than that of Ni-N4 catalyst without phosphorus modification.Besides,Ni-P1N3 performed the highest CO Faradaic efficiency(FECO)of 85.0%–98.0%over a wide potential range of−0.65 to−0.95 V(vs.the reversible hydrogen electrode(RHE)).Experimental and theoretical results revealed that the asymmetric Ni-P1N3 site was beneficial to CO_(2)intermediate adsorption/desorption,thereby accelerating the reaction kinetics and boosting CO_(2)RR activity.This work provides an effective method for preparing well-defined dual-coordinated SSCs to improve catalytic performance,targetting to CO_(2)RR applications.

Construction of amorphous/crystalline heterointerfaces for enhanced electrochemical processes

Amorphous nanomaterials have emerged as potential candidates for energy storage and conversion owing to their amazing physicochemical properties.Recent studies have proved that the manipulation of amorphous nanomaterials can further enhance electrochemical performance.To date,various feasible strategies have been proposed,of which amorphous/crystalline(a-c)heterointerface engineering is deemed an effective approach to break through the inherent activity limitations of electrode materials.The following review discusses recent research progress on a-c heterointerfaces for enhanced electrochemical processes.The general strategies for synthesizing ac heterojunctions are first summarized.Subsequently,we highlight various advanced applications of a-c heterointerfaces in the field of electrochemistry,including for supercapacitors,batteries,and electrocatalysts.We also elucidate the synergistic mechanism of the crystalline phase and amorphous phase for electrochemical processes.Lastly,we summarize the challenges,present our personal opinions,and offer a critical perspective on the further development of a-c nanomaterials.