近年來，滲透能源因其清潔和可持續的特性而引起了大量的關注。滲透能可以透過反向電滲析技術收集，並使用離子選擇性膜將儲存在離子濃度梯度中的化學勢能轉化為電能。然而，在過去文獻所報告的微小納米通道中存在著高電阻和低離子通量的問題，因此滲透發電的性能受到了限制。在此，我們開發了一種基於中尺度離子二極體的混合系統p-MXene@MC，其由二維多孔Ti3C2Tx MXene (p-MXene)和一維錐形單孔PET次微米尺度通道（MC）構成。此混合通道中高度幾何不對稱的特點賦予了p-MXene@MC優異的離子選擇性和出色的離子電流整流特性(或稱為離子二極體特性)，使薄膜在一個方向上放大離子傳輸。除了實驗結果外，我們還使用了基於泊松-能斯特-普朗克（PNP）和納維-斯托克斯（NS）模型的數值模擬來揭示離子二極體效應源於在大尺寸單通道MC基材上引入p-MXene次納米通道。受益於強離子二極體效應以及多孔MXene垂直通道中較快的離子傳輸，p-MXene@MC在1000倍KCl濃度梯度以及中性環境下產生了345 pW的創紀錄滲透功率，優於所有先前報導的單孔滲透能源產生器。此外，p-MXene@MC系統可以承受苛刻的化學條件，因此從酸性溶液中的質子濃度梯度中收集滲透能是可行的，其在1000倍質子梯度下輸出功率可達1000 pW以上。我們還將p-MXene@MC的離子電流整流特性和滲透發電性能與由MXene通道層和 MC 組成的系統(MXene@MC)進行了比較。結果表明，前者能夠產生更高的放大離子電流和滲透性能。我們期望本研究可以為高性能滲透能源產生器開闢一條嶄新的途徑。

Recently, osmotic power has garnered considerable attention owing to its environmentally friendly and sustainable attributes. One effective method for harnessing osmotic power is through the process of reverse electrodialysis. This approach involves the conversion of the chemical potential energy stored in an ionic concentration gradient into electrical energy, facilitated by the use of ion-selective membranes. Nevertheless, the potential of osmotic power generation is somewhat constrained by the restricted ion flux within the small-scale nanochannels. Herein, we report a hybrid mesoscale ionic diode system (p-MXene@MC), constructed from two-dimensional porous Ti3C2Tx MXene (p-MXene) and a single conical PET mesochannel (MC). The high asymmetry in channel geometry of p-MXene@MC grants the membrane with remarkable ion selectivity and an exceptional ion current rectification (ICR) property (or called ionic diode property) which allow the membrane transporting ions in one direction with amplified property. In addition to experimental results, we employ the numerical simulation based on the Poisson-Nernst-Planck (PNP) and Navier-Stokes (NS) model to unravel that the ionic diode effect stems from the introduction of p-MXene subnanochannels onto the large-sized single MC substrate. Benefiting from strong ionic diode effect and enhanced ion transport from vertical porous MXene channels, the p-MXene@MC produces a record high osmotic power of 345 pW under a 1000-fold KCl gradient at neutral pH. This remarkable achievement surpasses the capabilities of all existing single-pore devices. Furthermore, the p-MXene@MC system can withstand harsh chemical conditions, which makes it suitable for harvesting energy from proton concentration gradients. The output power can reach over 1000 pW at a 1000-fold proton gradient. We also compare the ICR property and osmotic power generation performance of the proposed p-MXene@MC with the system, composed of rigid MXene channels layer and MC (MXene@MC). The results clearly demonstrate that the former exhibits superior performance in amplifying ionic current and osmotic power. We anticipate that the findings of this study will serve as a pioneering platform for achieving high-performance osmotic power generation.

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