The elimination of possible defects is indispensable in making zeolite membranes popular in process industries. A novel counter‐diffusion chemical liquid deposition (CLD) technique is proposed and developed for selective defect‐patching of zeolite membranes. Dodecyltrimethoxysilane (DMS) is employed as the silane coupling agent, forming a protective layer on the membrane surface so that intracrystalline pores can be kept intact in the subsequent reparation step. By using tetraethoxy orthosilicate (TEOS) and (3‐chloropropyl)triethoxysilane (3CP‐TES), co‐hydrolysis and co‐condensation at the organic/aqueous interface fabricate the silsesquioxane/silicate hybrid on macro‐, meso‐ and even microdefects. The silicalite‐1 membrane before and after reparation is characterized using contact‐angle measurements, Fourier transform IR spectroscopy, and electron probe microanalysis. Permporometry is conducted to study the pore‐size distribution of the membrane before and after reparation. It is found that the silsesquioxane/silicate hybrid is only deposited at the pore‐mouth of the defects, and the defects can be plugged to less than 1.3 nm pores after patching. After reparation, the separation factor of a 50/50 n/i‐butane‐gas mixture through the membrane can be increased to 35.8 from 4.4, and the separation factor of a CO2/N2 gas mixture through the membrane can be increased to around 15 from 1, while keeping the two‐thirds CO2 permeation flux of the synthesized membrane.

We have designed and synthesized two low bandgap conjugated copolymers containing alternating meta-fluoro-p-alkoxyphenyl-(m-FPO-) or p-fluoro-m-alkoxyphenyl-(p-FPO-) substituted benzodithiophenes-co-benzooxadiazole (BO), named PBO-m-FPO and PBO-p-FPO. The properties, including UV−vis absorption, charge mobility and photovoltaic performance of the two polymers have been intensively investigated. The results indicated that the introduction of fluorine atom at m, p positions of phenyl substituted benzodithiophene unit hardly affected their absorption spectra and highest occupied molecular orbital (HOMO) level. However, the two polymers showed different photovoltaic properties. Power conversion efficiencies (PCEs) based on the device structure of ITO/PEDOT:PSS/polymer:PC 71 BM/ Ca/Al demonstrated a large distinction (5.9% for PBO-m-FPO vs 2.8% for PBO-p-FPO) at optimal weight ratio. When replacing the Ca layer with zirconium acetylacetonate (ZrAcac), using 3% 1,8-diiodooctane (DIO) as the active layer additive, the PCEs of PBO-m-FPO and PBO-p-FPO increased by 36% (8.0% vs 5.9%) and 85% (5.1% vs 2.8%), respectively. The active layer's mobilities, morphology and molecular packing resulted in a significant difference in short-circuit current density (J sc ) and fill factor (FF). ■ INTRODUCTIONPolymer solar cells (PSCs) based on bulk heterojunction (BHJ) have made tremendous advances toward commercialization. 1 Recently, the power conversion efficiencies (PCEs) of several polymers with single junction device have reached 11%. 2−5 As impressive and important renewable energy sources, PSCs have particular advantages such as simple device structure, lightweight, flexibility and low fabrication cost using simple ambient-condition solution or the roll-to-roll coating process. 6−8 Compared to inorganic-based solar cells, however, they still do not achieve the targeted 15% efficiency and satisfying lifetime, which is required for widespread commercialization. 9 Although optimizing the device fabrication 10,11 will improve photovoltaic performance, a promising candidate polymer with simple synthesis process is extremely in demand for broad applications of PSCs. 12 For high-performance PSCs, the ideal strategy is to design donor−acceptor (D−A) alternating molecular structure for BHJ solar cell, which can offer the unique feature of tuning the energy levels and the bandgap. 13 As well-known, PCE is proportional to the open-circuit voltage (V oc ), short-circuit current density (J sc ), and fill factor (FF). So we can independently modulate D−A copolymers to obtain a lowlying the highest occupied molecular orbital (HOMO) energy

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