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Multidimensional perovskite techniques are of intense research interest since they are proved to be advantageous to enhance the perovskite stability. Thereinto, the structure engineering strategy has been widely used to regulate the low dimensional (LD) perovskite structures and obtain expected optoelectronic properties. In this work, we intercalate a thus far unreported metallic coordination compound [Ga-Tpy2]3+ (Tpy: 2,2';6',2″-terpyridine) to the inorganic Pb-I building block as the A-site organic group, and the zero dimensional (0D) [Ga-Tpy2]PbI5 perovskite-like single crystal is obtained. This material displays suitable band edge levels, which enable its potential application as light absorber in solar cells. The DFT calculations manifest delocalized charge distribution on Tpy ligands that can facilitate electron transport, which is attributed to the formation of a double hybrid coordinate bond, i.e., σ bonds and π bonds, between Ga3+ ions and Tpy ligands. These coordinate bonds make metallic complexes promising molecules to regulate structure-associated optoelectronic performances of the LD perovskites.

Owing to the high toxicity of Pb-based hybrid perovskites, a hypotoxic element, e.g., Sn, was employed to partially or completely replace Pb with the aim of gaining environmentally friendly lead-fr...

Cs xFA1- xPbI3 single crystals are expected to provide more excitement in optoelectronic applications, including photodetector, laser, light-emitting diode, etc. Herein, we aim to gain an in-depth understanding of the growth mechanisms of perovskite single crystal with various morphologies in view of microscopic dynamics by the combination of component, structure, and solvent engineering. A sequence of Cs xFA1- xPbI3 (0 ≤ x ≤ 0.14) perovskite single crystals with a dodecahedron morphology and tunable aspect ratio can be obtained by means of a solution-processed uniform-cooling approach. The optimized Cs0.1FA0.9PbI3 single crystals prepared in γ-butyrolactone mixed with dimethyl sulfoxide are theoretically and experimentally demonstrated to have superior performances, e.g., extremely higher long-term stability, lower trap density, and higher mobility. The broadband absorption, i.e., 300-910 nm, enables its application in near-infrared detection (880 nm), and the corresponding detector demonstrates higher responsivity at different light intensities and a fast photocurrent response (τ1 = 11 μs, τ2 = 10 μs). Equally important, we also explore the application of optimized Cs0.1FA0.9PbI3 single crystals with a tunable aspect ratio in an X-ray detector and the extremely high sensitivity (2772.1 μC Gyair-1 cm-2 under a bias of 150 V) demonstrates their good potential for radiation detection.

Dimensionality engineering has proved to be a reliable strategy for addressing the issue of perovskite stability. In this study, a series of previously unreported low-dimensional organic–inorganic hybrid perovskite single crystals were designed and grown by following a simple hydrothermal approach involving solution processing. The as-prepared terpyridine-derived perovskite single crystals displayed tunable structures and electronic dimensionality, which was closely associated with the crystal growth conditions. The performed DFT calculations suggested that the fluctuating conduction band edge demonstrates obvious charge delocalization associated with the π-conjugation effect, a feature promoting efficient charge transport by means of coupling structural dimensionality and electronic dimensionality. This study has provided new ideas for the design of new materials to be used in fields involving photovoltaic devices.

A new “bottom up” strategy via incorporating specific fillers into polymeric matrix and forming rough surface as well as exposed fillers without further surface treatment is presented to replace conventional palladium (Pd) activation or molecular grafting in polymer surface metallization hopefully. Transmission electron microscope (TEM), 3D profile, cross-cut testing and surface enhanced Raman spectroscopy (SERS) were conducted to studied the the effects of fillers in generating rough surface and improving adhesion. The results showed that, 1D/ 2D, functionalized fillers generated rougher surface, adhesion improved significantly after functionalization. Before functionalization, the adhesion is influenced by surface roughness and original functional groups of the fillers and after functionalizaton, the adhesion is depended by the mechanical properties and behaviors of the fillers.

Despite the rapid development of CsPbIx Br3-x (0 ≤ x ≤ 3) inorganic perovskite solar cells, associated with their superior thermal stability, their low moisture stability limits their commercial deployment. In this study, 1D-2D-3D multidimensional coupled perovskites are prepared by means of an in situ self-integration approach. This pioneering method allows incorporating thus far unreported 1D-Tpy2 Pb3 I6 and 2D-TpyPb3 I6 (Tpy; terpyridine) perovskites. Heterojunction perovskites demonstrate superior stability against water in comparison with control 3D CsPbI2 Br, which is related to the hydrophobicity of low-dimension (LD) perovskites. Remarkably, the spontaneous involvement of LD perovskites can adjust/reconstruct the interfacial structure. This modification allows releasing the residual strain, establishing effective charge transfer channels that increase the carrier transport ability. Accordingly, 1D-2D-3D hybrid CsPbI2 Br perovskite solar cells demonstrate a stabilized power conversion efficiency as high as 16.1%, which represents a very significant improvement, by a factor of 43%, with respect to control 3D CsPbI2 Br perovskite solar cell. Equally importantly, the multidimensional coupled perovskite solar cells exhibit extraordinary stability, well above 1000 h in ambient atmosphere.

Weak plating performance and poor adhesion between epoxy and silver coatings can restrict the development of miniaturized electronic devices and multi-layer circuits. In this work, we fabricate a novel epoxy-based nanocomposite containing -SH and -NH2 dual functionalized multi-walled carbon nanotubes (d-MWCNTs), with enhanced adhesive properties towards silver particles. The enhanced adhesion mechanisms are also investigated by 3D profiling, scanning electron microscopy, cross-cut test, and Raman spectroscopy. Introducing d-MWCNTs improved the surface roughness of the nanocomposites, but the improvements become unstable when the d-MWCNTs content exceeded 0.6 g/15 g epoxy. In addition, the d-MWCNTs are found to affect the size and shape of the coated silver particles. Besides, we find that neither NH2-dominated nor SH-dominated functionalization improve the adhesion effectively, while a balance proportion of the two (v(-NH2) silane: v(-SH) silane = 4:6) does. These findings may open the door for the simplification and optimization of epoxy-metal plating for multi-layer circuit applications.

The lack of thermal conductance (TC) remains to be a challenge for epoxy resin. Fortunately, the thermal conductance of epoxy resin can be effectively improved by filler incorporation. Recently, compositing epoxy resin with hybrid filler system has been the direction for the development of next-generation thermal conductive functional materials. In this paper, epoxy-based nanocomposites containing nanodiamonds (DNDs)/pristine multi-walled carbon nanotubes (p-MWCNTs) and DNDs/KH550 functionalized MWCNTs (MWCNTs-KH) as the hybrid filler system were prepared respectively, and the thermal conductance of the nanocomposites was compared. The addition of DNDs was found to play a dominating role in the MWCNTs-KH filler systems (0.2 g, from 0.30 W/mK to 0.34 W/mK), but hardly has any effect on the p-MWCNTs filler system (0.2 g, from 0.24 to 0.26 W/mK only). Furthermore, the TC of the DNDs/MWCNTs-KH (2 g) epoxy-based nanocomposite increased to 0.45 W/mK, displaying an enhancement of 114.2 %. A shift of 5 cm-1 recorded by FTIR and the shift of C O revealed by XPS for DNDs/MWCNTs-KH strongly confirmed the existence of hydrogen bonds. Associating with the characterization results of SEM, TEM and dispersion qualitative experiment, the significant improvement in the TC of DNDs/MWCNTs-KH (2 g) epoxy-based nanocomposite was attributed to the hydrogen bond attachment between DNDs and MWCNTs-KH. The mechanism is that the attachment improves the dispersion of the fillers in epoxy, leading to the formation of a more effective thermal conductive network, thus, the enhanced TC. This work may inspire future studies in hybrid filler recognition and self-assemble technology via hydrogen bonds.