ACS Applied Energy Materials最新文献

Adding short-chain methylammonium chloride (MACl) into the precursor solution of formamidine lead iodide (FAPbI₃) is a commonly adopted strategy. This addition facilitates the generation of the α-phase and increases the grain size significantly. These changes in turn optimize the light absorption characteristics of perovskite thin films, thereby obtaining a high-quality perovskite thin film with uniform morphology and at the same time enhancing the power conversion efficiency (PCE) of perovskite solar cells (PSCs). However, there are few reports of the use of longer alkylammonium chloride salts added to perovskite precursor solutions. Herein, we deliberately elected to introduce 2-fluoroethyl-1-amine hydrochloride (FEACl) into FAPbI₃ as an alternative to MACl. The results indicate that FEACl can interact with perovskite precursors; this approach effectively enhances the crystallinity of perovskite thin films while promoting the stabilization of the α-FAPbI₃ phase. Moreover, the large cations of FEACl are not incorporated into the lattice, which minimizes the change in the band gap of FAPbI₃. The results show that PCE of the optimal device has increased from 23.07% of MACl treatment to 24.30% of FEACl treatment, and the filling factor (FF) has also increased from 81.95 to 84.37%, respectively. When unpackaged devices are stored at room temperature with a relative humidity ranging from 20 to 30% for 1000 h, the PCE is observed to be maintained at 83.57% of its initial value.

Understanding the intricate electrochemical processes in solid oxide fuel cell (SOFC) components, especially air electrodes, is crucial for enhancing device performance and durability. In this work, following recent results showing important improvements in the electrochemical performance of SOFCs with room-temperature sputtered gadolinium-doped ceria (GDC) barrier layers, we investigate by standard Distribution of Relaxation Time (DRT) analysis the influence of the GDC thickness and uniformity on the cathodic reaction kinetics. The outcomes highlight the role played by the GDC thickness in the oxygen reactions at the electrolyte/cathode interface and the GDC thickness uniformity in the anode electrochemical charge transfer reactions involving oxygen ions from the cathode. The results of our work, obtained for industrial-scale SOFCs, are particularly interesting in view of enhancing both their performance and stability.

High efficiency and low cost are indispensable for the industrialization of organic solar cells (OSCs), which urgently needs to be addressed. Herein, three simple-structure terpolymer donors, PTQ13-5, PTQ13-10, and PTQ13-15, are developed by embedding a simple fluorinated unit 3-fluorothiophene (T-F) into the molecular backbone of polymer PTQ10 to pursue low-cost and high-efficiency organic photovoltaic molecules. Three terpolymers show obviously low-cost characteristics due to their short synthesis routes and high total synthetic yields from cheap raw materials. The introduction of the T-F unit leads to the blue-shifted absorption, down-shifted HOMO levels, and more favored molecular aggregation morphology of terpolymers, mainly due to the strong electron-withdrawing property of the F atom, along with the presence of noncovalent F···H interactions. As a result, the PTQ13-5-based OSC achieves enhanced power conversion efficiency (PCE) of 18.42% due to suppressed voltage loss (V_loss) because of low nonradiative loss of 0.189 eV and enhanced charge generation; this is one of the highest PCEs for OSCs based on low-cost organic photovoltaic materials. This work suggests that fluorination of the polymer backbone is an effective strategy to suppress V_loss and improve charge generation of OSCs, and it offers a rational guide in the design of organic photovoltaic molecules with low cost and high performance.

Sulfide electrolyte Li₇P₂S₈I has received extensive attention on account of its high ionic conductivity and remarkable stability. However, a long processing time and sophisticated synthesis procedures are generally required. In this study, Li₇P₂S₈I is synthesized through the combination of melt-quenching and high-energy ball milling, significantly reducing ball milling time compared with the conventional mechanical milling method. The generation of highly conductive thio-LISICON II phase facilitates the fast Li⁺ transportation. The optimized Li₇P₂S₈I exhibits a favorable powder cold-pressed ionic conductivity of 1.51 mS cm^–1 and a relatively high critical current density of 0.55 mA cm^–2. The resultant LiCoO₂/Li₇P₂S₈I-700/Li all-solid-state battery delivers an initial reversible capacity of 119.1 mAh g^–1 with a capacity retention of 91.5% after 20 cycles under 0.1 C. This study introduces an efficient approach for the rapid synthesis of Li₇P₂S₈I for all-solid-state lithium batteries.

Tellurium-doped nickel manganese layered double hydroxide (Te-NiMn LDH) is synthesized, featuring direct growth on a cetyltrimethylammonium bromide (CTAB)-modified MXene layer (C-MXene) anchored to an ultraviolet-ozone-treated nickel foam (Te-NiMn LDH/C-MXene/NF). This innovative material serves as a high-performance active material in supercapacitors. The modification of MXene using a CTAB-containing ethanol solution leads to increased interlayer spacing, which facilitates ion transport and enhances electrical conductivity. The C-MXene layer on a nickel foam provides an effective conductive substrate that supports the growth of LDH and the incorporation of tellurium and hence eliminates the need for binders or additives. This not only reduces fabrication costs but also minimizes internal resistance. Tellurium doping can increase the electron density within the LDH structure and enhance the valence states and therefore its capacitance. The binder-free Te-NiMn LDH/C-MXene/NF electrode demonstrates a high specific capacitance of 1920 F/g at 2 A/g. Furthermore, the hybrid supercapacitor composed of Te-NiMn LDH/C-MXene/NF and activated carbon electrodes achieves a specific capacitance of 202.6 F/g, maximum energy density of 52.3 Wh/kg, and maximum power density of 6452 W/kg. The excellent cycling stability with a capacitance retention of 77.3% after 10,000 cycles is also obtained for this device.

Self-powered systems, particularly those utilizing triboelectric nanogenerator (TENG), have emerged in the field of electronics for their ability to continuously convert environmental mechanical energy into electrical energy, powering portable devices without external sources. This research demonstrates an energy harvester for self-powered electronics and a self-sustained electrochromic system combined with a TENG that harvests electricity from biomechanical motion. The electrochromic-material inspired TENG (EC-TENG) is fabricated using electrospun PPy/PEO/2D-MnO₂-based hybrid nanofiber mats and polytetrafluoroethylene (PTFE). The as-synthesized materials were confirmed by using multiple techniques, including X-ray diffraction, Raman spectroscopy, FTIR spectroscopy, and scanning electron microscopy. The fabricated EC-TENG with optimized 3.5 wt % 2D-MnO₂ has generated 93 V of open-circuit voltage and 1.7 μA of short-circuit current under hand-tapping force. The instantaneous power density was calculated as 50 μW/cm² at a load resistance of 40 MΩ. Stability studies for 2000 cycles are performed on the EC-TENG, which shows outstanding performance with minimal changes in voltage output. For practical applications, the EC-TENG has been used as a power supply for small-scale electronics such as LEDs and a digital hygrometer. Additionally, a mechano-tribo-electrochromic device has been developed, in which EC-TENG converts bio-mechanical energy (finger tapping) to electricity for powering the electrochromic device based on PPy/2D-MnO₂. This mechano-triboelectrochromic device exhibits monochromatic transitions, making it suitable for applications such as electronic billboards. This research work offers a flexible approach for the creation of future self-powered electronic systems while also advancing the field of self-sustaining electrochromic devices and highlighting the broader use of EC-TENGs in energy-harvesting technologies.

Bulk-phase Mo doping as well as multiple coatings of ion-conducting LiAlO₂/Al₂O₃ and electron-conducting PPy polymers were applied to modify layered Ni-rich cathode materials. Mo ions effectively stabilized the crystal lattice, suppressing anisotropic lattice changes and reducing the generation of microscopic cracks and dislocations, thus stabilizing the crystal and phase structures. The LiAlO₂/Al₂O₃ coating reduced the lithium residue on the surface, which in turn greatly inhibited the generation of the inert layer during charging and discharging. At the same time, the diffusion rate of Li⁺ was improved. The thin and uniform PPy coating layer effectively avoided direct contact between the cathode material and electrolyte, blocking harmful side reactions while increasing the electron-transfer rate at the interface. The elastic PPy shell resisted internal pressure, reducing macrocracks and electrolyte penetration. The structural stability as well as the ionic and electronic conductivities of the modified Ni-rich cathode material was improved. This resulted in a 13.1 mAh·g^–1 increase in the first discharge specific capacity of the modified Ni-rich oxide over the pristine NM75 at a 1C rate within 2.8–4.4 V at room temperature and a 12.8% increase in capacity retention after 100 cycles. Capacity retention after 100 cycles was improved by 8.1% at a 1C rate (2.8–4.3 V, 55 °C). The analysis results showed that the modified Ni-rich cathode material had a more stable crystal structure and a smaller degree of deformation. This design can be extended to other high-capacity cathode materials, which is expected to promote the development of high-performance cathode materials and improve the viability of lithium-ion batteries.

Doping in cadmium telluride (CdTe) thin-film solar cells is a critical step in producing highly efficient CdTe solar modules. To date, copper (Cu) ex-situ diffusion doping and group V in situ doping (such as arsenic, As) have been effectively used in manufacturing CdTe solar modules. However, Cu doping is prone to rapid degradation, whereas the low activation ratio of the dopants constrains group V in situ doping. Recently, ex-situ group V doping has been developed, showing an improved doping activation ratio through a solution process. In this study, we developed a vapor-based AsCl₃ doping method for diffusion doping of polycrystalline CdSeTe devices. AsCl₃ vapor annealing can promote the diffusion of As into the bulk CdSeTe through a surface chemical reaction between CdTe and AsCl₃. This approach has led to a long carrier lifetime of over 72 ns, V_oc of 850 mV, and power conversion efficiency of ∼18% with Au metal electrodes. The vapor-based ex situ group V doping approach offers an effective means to perform group V diffusion doping into the CdSeTe device.

Pt-based alloys with precisely controllable element distribution are highly sought after in catalysis. This study focuses on optimizing elemental distribution and alloying in PtNi alloy nanowires (NWs) through high-temperature heat treatment. The resulting PtNi alloy NWs with uniform elemental distribution (U-PtNi NWs) demonstrate exceptional stability, attributed to facilitated electron transfer and a denser Pt shell, in stark contrast to untreated NWs that suffer from elemental segregation and subsequent performance degradation during electrochemical testing. In methanol oxidation reaction tests, U-PtNi NWs demonstrated exceptional mass activity (1562.0 mA mg^–1) and specific activity (5.38 mA cm^–2), with minimal activity loss after 1000 cycles. This work emphasizes the significance of precise component control in developing high-performance catalysts and presents a strategy to enhance fuel cell performance through one-dimensional nanocomponent adjustment.

This research explores the impact of nickel (Ni) doping on the performance of SnS₂ photoelectrodes in water-splitting applications. A series of Ni-doped SnS₂ nanosheets with varying concentrations of Ni (3, 6, and 10 wt %) are synthesized using the hydrothermal method. The photoelectrochemical study reveals a significant ∼22 times increment in the photocurrent density, a decrease in the charge transfer resistance, and an improved IPCE value for 6 wt % Ni-doped SnS₂ (6-NSS) as compared to bare SnS₂. Mott–Schottky analysis reveals a negative shift in the flat-band potential (V_FB) for the 6-NSS photoelectrode, indicating increased band bending and improved charge carrier separation. This enhancement in PEC performance is attributed to the introduction of defects that act as trapping sites for charge carriers, thereby reducing the recombination rate of charge carriers. The BET analysis reveals that 6-NSS has a significantly higher surface area compared to bare SnS₂, suggesting the presence of more active sites available for PEC redox reactions. EIS studies support these findings by showing a lower charge transfer resistance in Ni-doped SnS₂, indicating improved charge transfer and separation efficiency. The results demonstrate that Ni doping significantly enhances the PEC performance of SnS₂, making it a promising photoanode for efficient water-splitting applications.