Nanoscale

doi: 10.1039/D3NR90036Cpmid: N/A

doi: 10.1039/D3NR90037Apmid: N/A

doi: 10.1039/D3NR90038Jpmid: N/A

Li, Zhaohan; Song, Jiaojiao; Li, Anming; Shen, Huaibin; Du, Zuliang

doi: 10.1039/d2nr07078bpmid: 36727444

As the emitters of quantum dots (QDs) light-emitting diodes (QLEDs), QDs, which are responsible for the charge injection, charge transportation, and especially exciton recombination, play a significant role in QLEDs. With the crucial advances made in QDs, such as the advancement of synthetic methods and the understanding of luminescence mechanisms, QLEDs also demonstrate a dramatic improvement. Until now, efficiencies of 30.9%, 28.7% and 21.9% have been achieved in red, green and blue devices, respectively. However, in QLEDs, some issues are still to be solved, such as the imbalance of charge injection and exciton quenching processes (defect-assisted recombination, Auger recombination, energy transfer and exciton dissociation under a high electric field). In this review, we will provide an overview of recent advances in the study and understanding of the working mechanism of QLEDs and the exciton quenching mechanism of QDs in devices. Particular emphasis is placed on improving charge injection and suppressing exciton quenching. An in-depth understanding of this progress may help develop guidelines to direct QLED development.

Chen, Tianyou; Peng, Yan; Qiu, Meishuang; Yi, Changfeng; Xu, Zushun

doi: 10.1039/d3nr00280bpmid: 36727557

Mixing-induced nanoprecipitation (MINP) is an efficient, controllable, scalable, versatile, and cost-effective technique for the preparation of nanoparticles. In addition to the formulation of drugs, MINP has attracted tremendous interest in other fields. In this review, we highlight recent advances in the preparation of nanoparticles with complex nanostructures via MINP and their emerging applications beyond biomedicine. First, the mechanisms of nanoprecipitation and four mixing approaches for MINP are briefly discussed. Next, three strategies for the preparation of nanoparticles with complex nanostructures including sequential nanoprecipitation, controlling phase separation, and incorporating inorganic nanoparticles, are summarized. Then, emerging applications including the engineering of catalytic nanomaterials, environmentally friendly photovoltaic inks, colloidal surfactants for the preparation of Pickering emulsions, and green templates for the synthesis of nanomaterials, are reviewed. Furthermore, we discuss the structurefunction relationships to gain more insight into design principles for the development of functional nanoparticles via MINP. Finally, the remaining issues and future applications are discussed. This review will stimulate the development of nanoparticles with complex nanostructures and their broader applications beyond biomedicine.

Aftab, Sikandar; Iqbal, Muhammad Zahir; Hegazy, Hosameldin Helmy; Azam, Sikander; Kabir, Fahmid

doi: 10.1039/d2nr07141jpmid: 36728545

Two-dimensional (2D) van der Waals (vdW) heterostructured transition metal dichalcogenides (TMDs) open up new possibilities for a wide range of optoelectronic applications. Interlayer couplings are responsible for several fascinating physics phenomena, which are in addition to the multifunctionalities that have been discovered in the field of optoelectronics. These couplings can influence the overall charge, or the energy transfer processes via stacking, separation, and dielectric angles. This focused review article summarizes the most recent and promising strategies for interlayer exciton emission in 2D or integrated perovskites and TMD heterostructures. These types of devices require a thorough comprehension and effective control of interlayer couplings in order to realize their functionalities and improve performance, which is demonstrated in this article with the energy or charge transfer mechanisms in the individual devices. An ideal platform for examining the interlayer coupling and the related physical processes is provided by a summary of the recent research findings in 2D perovskites and TMDs. Furthermore, it would encourage more investigation into the comprehension and regulation of excitonic effects and the related optoelectronic applications in vdW heterostructures over a broad spectral response range. Finally, the current challenges and prospects are summarized in this paper.

Bazazi, Sina; Hosseini, Seyedeh Parisa; Hashemi, Esmaeil; Rashidzadeh, Bahaaldin; Liu, Yuqian; Saeb, Mohammad Reza; Xiao, Huining; Seidi, Farzad

doi: 10.1039/d2nr07065kpmid: 36728615

C-dots are a new class of materials with vast applications. The synthesis of bio-based C-dots has attracted increasing attention in recent years. Polysaccharides being the most abundant natural materials with high biodegradability and no toxicity have been the focus of researchers for the synthesis of C-dots. C-dots obtained from polysaccharides are generally fabricated via thermal procedures, carbonization, and microwave pyrolysis. Small size, photo-induced electron transfer (PET), and highly adjustable luminosity behavior are the most important physical and chemical properties of C-dots. However, C-dot/polysaccharide composites can be introduced as a new generation of composites that combine the features of both C-dots and polysaccharides having a wide range of applications in biomedicines, biosensors, drug delivery systems, etc. This review demonstrates the features, raw materials, and methods used for the fabrication of C-dots derived from different polysaccharides. Furthermore, the properties, applications, and synthesis conditions of various C-dot/polysaccharide composites are discussed in detail.

Aftab, Sikandar; Hegazy, Hosameldin Helmy; Iqbal, Muhammad Zahir

doi: 10.1039/d2nr05337cpmid: 36734944

Two-dimensional (2D) layered semiconductors are appealing materials for high-specific-power photovoltaic systems due to their unique optoelectronic properties. The 2D materials can be naturally thin, and their properties can be altered in a variety of ways. Therefore, these materials may be used to develop high-performance opto-spintronic and photovoltaic devices. The most recent and promising strategies were used to induce circular photo-galvanic effects (CPGEs) in 2D TMD materials with broken inversion symmetry. The majority of quantum devices were manufactured by mechanical exfoliation to investigate the electrical behavior of ultrathin 2D materials. The investigation of CPGEs in 2D materials could enable the exploration of spin-polarized optoelectronics to produce more energy-efficient computing systems. The current research on nanomaterial-based materials paves the way for developing materials to store, manipulate, and transmit information with better performance. Finally, this study concludes by summarizing the current challenges and prospects.

Qu, Guangfei; Wei, Kunling; Pan, Keheng; Qin, Jin; Lv, Jiaxin; Li, Junyan; Ning, Ping

doi: 10.1039/d2nr06190bpmid: 36734996

The electrochemical CO2 reduction reaction can effectively convert CO2 into promising fuels and chemicals, which is helpful in establishing a low-carbon emission economy. Compared with other types of electrocatalysts, single-atom catalysts (SACs) immobilized on carbon substrates are considered to be promising candidate catalysts. Atomically dispersed SACs exhibit excellent catalytic performance in CO2RR due to their maximum atomic utilization, unique electronic structure, and coordination environment. In this paper, we first briefly introduce the synthetic strategies and characterization techniques of SACs. Then, we focus on the optimization strategies of the atomic structure of carbon-based SACs, including adjusting the coordination atoms and coordination numbers, constructing the axial chemical environment, and regulating the carbon substrate, focusing on exploring the structureperformance relationship of SACs in the CO2RR process. In addition, this paper also briefly introduces the diatomic catalysts (DACs) as an extension of SACs. At the end of the paper, we summarize the article with an exciting outlook discussing the current challenges and prospects for research on the application of SACs in CO2RR.

Conte, Andrea; Baron, Marco; Bonacchi, Sara; Antonello, Sabrina; Aliprandi, Alessandro

doi: 10.1039/d2nr06687dpmid: 36727608

Copper and silver nanowires have been extensively investigated as the next generation of transparent conductive electrodes (TCEs) due to their ability to form percolating networks. Recently, they have been exploited as electrocatalysts for CO2 reduction. In this review, we present the most recent advances in this field summarizing different strategies used for the synthesis and functionalization/activation of copper and silver nanowires, as well as, the state of the art of their electrochemical performance with particular emphasis on the effect of the nanowire morphology. Novel perspectives for the development of highly efficient, selective, and stable electrocatalysts for CO2 reduction arise from the translation of NW-based TCEs in this challenging field.