Solution Processing Research Articles

A Mini‐Review: The Rise of Triple‐Junction Silicon‐Perovskite‐Perovskite Solar Cells

Recently, the multijunction (MJ) solarcells have gained interest and have a lot of promise going forward. As MJ solarcells with an increasing number of absorber layers can reduce the thermalization and the nonabsorption losses of the device, it has then been proposed to overcome the Shockley–Queisser (S–Q) maximum efficiency limit. The preparation of the metal halide perovskite using a solution processing method with tunable bandgaps has made them an ideal candidate to integrate with the silicon photovoltaic, forming MJ silicon‐perovskite (Si‐PVK) solar cells. Benefitting from these, 33.90% power conversion efficiency (PCE) has been realized for the Si‐PVK MJ solar cell, which is comparable to the S–Q maximum efficiency limit in the range of ≈1.10–≈1.30 eV. Furthermore, the PCE of Si‐PVK solar cells can potentially increase with increasing the number‐junction of perovskite device. Taking advantage of this, the research on the triple‐junction (TJ) silicon‐perovskite‐perovskite (Si‐PVK‐PVK) solar cells has gained attention, although it is still in an early stage of development. In this mini‐review, the working mechanism, the design principle, and the progress of TJ Si‐PVK‐PVK solar cells are discussed. Finally, future outlooks in this field are also provided.

Nitrogen-Rich Conjugated Macrocycles: Synthesis, Conductivity, and Application in Electrochemical CO2 Capture.

Here we report a series of nitrogen-rich conjugated macrocycles that mimic the structure and function of semiconducting 2D metal-organic and covalent organic frameworks while providing greater solution processability and surface tunability. Using a new tetraaminotriphenylene building block that is compatible with both coordination chemistry and dynamic covalent chemistry reactions, we have synthesized two distinct macrocyclic cores containing Ni-N and phenazine-based linkages, respectively. The fully conjugated macrocycle cores support strong interlayer stacking and accessible nanochannels. For the metal-organic macrocycles, good out-of-plane charge transport is preserved, with pressed pellet conductivities of 10-3 S/cm for the nickel variants. Finally, using electrochemically mediated CO2 capture as an example, we illustrate how colloidal phenazine-based organic macrocycles improve electrical contact and active site electrochemical accessibility relative to bulk covalent organic framework powders. Together, these results highlight how simple macrocycles can enable new synthetic directions as well as new applications by combining the properties of crystalline porous frameworks, the processability of nanomaterials, and the precision of molecular synthesis.

A Personal Journey in Nanoscience via Developing and Applying Liquid Phase TEM

AbstractLiquid phase TEM has attracted widespread attention in recent years as a groundbreaking tool to address various fundamental problems in nanoscience. It has provided the opportunity to reveal many unseen dynamic phenomena of nanoscale materials in solution processes by direct imaging through liquids with high spatial and temporal resolution. After my earlier work on real‐time imaging of the nucleation, growth, and dynamic motion of nanoparticles in liquids by developing high‐resolution liquid phase transmission electron microscopy (TEM) down to the sub‐nanometer level, I established my own research group at Lawrence Berkeley National Lab in 2010. My group focuses on developing and applying liquid phase TEM to investigate complex systems and reactions. We have studied a set of scientific problems centered on understanding how atomic level heterogeneity and fluctuations at solid‐liquid interfaces impact nanoscale materials transformations using advanced liquid phase TEM. This article describes my personal journey in nanoscience, highlighting the main discoveries of my research group using liquid phase TEM as a unique tool. Some perspectives on the impacts of liquid phase TEM and the future opportunities in nanoscience and nanotechnology enabled by liquid phase TEM are also included.

Lead Sulfide Quantum Dots as the Semiconductor Layer in Thin-Film Phototransistors for Infrared Thermal Image Sensing

Abstract This paper utilizes lead sulfide quantum dots, known for their high absorption coefficients, ease of solution processing, and high stability in air, as the semiconductor layer in thin-film phototransistors. These are combined with the most mature glass panel processing technology to create an infrared sensing device characterized by simple manufacturing processes, low production costs, small sensing areas, and large-area sensing capabilities. The novel lead sulfide quantum dot infrared sensing device proposed here exhibits remarkable performance at room temperature and under uncooled operation. It demonstrates a temperature sensitivity above 300oC for radiation temperature measurement, a fast total response time of 69 µs, and performance metrics such as noise of 1.9×10-12 A/Hz1/2, a maximum responsivity of 103 A/W, and a maximum detectivity of 2.04×1013 Jones. Therefore, the experimental results obtained here are significant for the research and design of future advanced quantum dot-based thermal imaging sensing applications.

Tuning the bandgap without compromising efficiency: ambient solution processing of Ge-alloyed (Ag,Cu)2Zn(Sn,Ge)(S,Se)4 kesterite thin-film solar cells

The photovoltaic sector currently experiences a growing demand for deeply-integrated technologies in agriculture, buildings, vehicles, among others. Kesterite compounds provide a versatile solution through their tunable bandgap via isovalent alloying. However, this should be done while preserving material opto-electronic quality and device performance, which is an unresolved challenge. Indeed, tuning the bandgap of kesterites must ensure low crystalline disorder to counteract the associated open-circuit voltage (Voc) losses when used in solar cells. To achieve this goal, this work introduces a simple molecular ink recipe realized in ambient air to process single-phase high-quality Ag,Gealloyed kesterite absorbers. By varying the Ge content from 0 to 100%, the absorber bandgap covers the range from 1.15 to 1.5 eV, in which the Urbach energy remains close to 20 meV and promisingly low Voc deficits are observed. In particular, the champion efficiency of 12.1% obtained with 40% Ge breaks the record for Ge-alloyed kesterites with a 1.2 eV bandgap by remarkably reaching 62% of the Shockley-Queisser limit for Voc. This study demonstrates a promising strategy to solve the issue of large band tailing and low opto-electronic quality in widebandgap kesterites while establishing a foundation for solution-processed kesterite solar cells with tunable bandgap and promising performance.

A Survey Paper on Plastic Solar Cell Technology

The demand of energy is increasing day by day so non-conventional source of energy has to be used. Sun is the nonconventional source of energy. Conventional solar panels convert solar energy into electrical energy. A plastic solar cell is the type of photovoltaic that makes use of organic electronics dealing with conductive organic polymers or small molecules for light absorption and charge transport to produce electricity from sunlight by the photovoltaic effect. Polymers Provide the Advantage of Solution Processing at Room Temperature, which is Less Expensive and Enables One to Use Plastics. Therefore, If Silicon Is Replaced with Polymer Nanowires, The Solar Cell Would Be Much Lighter and Ultimately Less Costly. These Solar Cells are Thin, Several Microns in Diameter, and Scavenge All the Rays from the Sun's Radiation. Plastic Solar Cell Technology is Based on Conjugated Polymers and Molecules. Polymer Solar Cells have Generated Considerable Interest Since it Provides Environmentally Friendly, Flexible, Lightweight, Low Cost, Possibility of High-Efficiency Solar Cells in the Last Couple of Decades. Plastic Solar Cells are More Efficient and Viable in Usage. This dissertation focuses on the development and optimization of plastic solar cell technology, in particular this potential towards flexible, lightweight, and cost-effective alternative sources to traditional silicon-based solar cells. The focus of the present research work is to find optimum organic materials for higher efficiency and stability in plastic solar cells, varying from conjugated polymers to small organic molecules. Some of the main goals are improving the charge transport mechanisms and optimizing the architecture of devices through state-of-the-art techniques of fabrication, like roll-to-roll printing and layer-by-layer deposition. The other key aspect is that the project assesses the environmental aspects and lifecycle of plastic solar cells to ensure an environmentally friendly production process. Huge preliminary results were achieved at high power conversion efficiencies and durability has been greatly improved, targeting very wide spread application from portable electronics up to building-integrated photovoltaics. Therefore, the discovery of plastic solar cells might be a major step for applicable solutions in renewable energy and towards overcoming the world's increasing energy challenges.

Insights into the Solution Processing of Non-van der Waals Boron Carbide.

Exfoliation of non-layered materials is crucial to unleash their enormous potential in wide range of applications. However, the presence of strong non-van der Waals interactions in all three dimensions makes exfoliation challenging. Boron carbide (B4C), known for its high hardness, holds great potential for diverse applications. In this work, B4C is exfoliated in 29 solvents to determine its Hansen solubility parameters (HSP) and understand the dispersion stability. The experimentally determined HSP values are 19.6, 15.3 and 15.1 MPa1/2 for dispersive interactions (δD), polar interactions (δP) and hydrogen bonding interactions (δH), respectively. Subsequently, in situ dispersion stability is analyzed qualitatively and quantitatively from the space-time resolved extinction profiles employing an analytical centrifuge. The sedimentation kinetics of B4C dispersions are analyzed using instability index, integral extinction and sedimentation velocity. B4C dispersions in solvents like ε-caprolactone, isopropyl alcohol, propylene carbonate and formamide exhibited excellent stability. Additionally, B4C nanosheets are utilized to investigate their field emission properties. These nanosheets exhibit a turn-on electric field of 3.35 V/μm at an emission current density of 1 μA cm-2, and it delivered a large emission current density of ~ 375 μA cm-2 at an applied electric field of 5.7 V/μm.

Scalable Production of Metal Oxide Nanoparticles for Optoelectronics Applications.

This work describes the scalability process of a continuous-injection protocol employed to produce tin-doped indium oxide nanocrystal dispersions. Different levels of manipulation starting from the synthesis and processing also related to the tuning of the optical response (considering the peculiar combination of UV and NIR absorption with visible transparency) make these materials incredibly versatile. But one of the most attractive features concern the modulation of their charge carrier density through chemical or post-synthetic doping, as for the case of core-shell materials, expanding the properties of the core composition. In addition, the colloidal nature of such materials allows for easy solution processing which enables an extensive use in different applications within current thin films base technologies.

Sustainable Green Solvents for Lead Halide Perovskites

AbstractLead halide perovskites have revolutionized the field of optoelectronics and attracted worldwide attention due to their outstanding semiconducting characteristics. Meanwhile, solution processability and printability of the perovskite allow the commercialization of perovskite solar cells (PSCs) profitable. However, deposition of the perovskite films usually uses polar aprotic solvents. The popular antisolvents are aromatics or aromatic halogenated hydrocarbons. All of them have a high risk of toxicity and flammability. To reduce the adverse effects on the environment and operators and enhance the sustainability of perovskite technologies, researchers have made lots of efforts to study sustainable green solvents. Herein, the selection criteria of green solvents are surveyed. Methods of solubility prediction of precursor solvents are comprehensively discussed from the perspectives of polarity and Lewis acid–base chemistry. The significance of antisolvent polarity and boiling point is emphasized. Research advances in green solvents are summarized. Finally, this review presents in‐depth insights into green‐solvent‐processable perovskites and highlights research directions for perovskite modules in the future. It lays a good foundation for the commercialization and sustainable development of PSCs.

Organic ferroelectric transistors with composite dielectric for efficient neural computing

Organic ferroelectric field-effect transistors (Fe-OFETs) exhibit exceptional capabilities in mimicking biological neural systems and represent one of the primary options for flexible artificial synaptic devices. Ferroelectric polymers, such as poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)), given their strong ferroelectricity and facile solution processing, have emerged as the preferred choices for the ferroelectric dielectric layer of wearable devices. However, the solution processed P(VDF-TrFE) films can lead to high interface roughness, prone to cause excessive gate leakage. Meanwhile, the ferroelectric layer in neural computing and memory applications also faces a trade-off between storage time and energy for read/write operations. This study introduces a composite dielectric layer for Fe-OFETs, fabricated via a solution-based process. Different thicknesses of poly(N-vinylcarbazole) (PVK) are shown to significantly alter the ferroelectric hysteresis window and leakage current. The optimized devices exhibit synaptic plasticity with a transient current of 3.52 mA and a response time of approximately 50 ns. The Fe-OFETs with the composite dielectric were modeled and integrated into convolutional neural networks, achieving a 92.95% accuracy rate. This highlights the composite dielectric's advantage in neuromorphic computing. The introduction of PVK optimizes the interface and balances device performance of Fe-OFETs for neuromorphic computing.

Comparison of Homogeneous Anion-Exchange Membrane Based on Copolymer of N,N-Diallyl-N,N-dimethylammonium Chloride and Commercial Anion-Exchange Membranes in Electrodialysis Processing of Dilute Sodium Chloride Solutions

In this study, we investigated the electrodialysis process for treating a dilute sodium chloride solution using various anion exchange membranes – specifically, the commercial heterogeneous MA-41 and homogeneous Neosepta AMX, along with the experimental homogeneous membrane MA-1. We observed an increase in the desalting rate and the limiting current for the studied anion-exchange membranes in the series MA-41, MA-1, and AMX. We found that with commercial membranes, the decrease of the solution concnetration leads to the development of conjugated effects of concentration polarization. For the AMX membrane, useful mass transfer due to electroconvection increases, whereas for the MA-41 membrane, the flux of salt ions decreases due to the occurrence of the water dissociation reaction. For the MA-1 membrane, a decrease in the solution concentration leads to a transition of the system to the underlimiting current mode. This behavior may be associated with a significant contribution of equilibrium electroconvection to the process of ion transfer in dilute solutions in electromembrane systems with this membrane. Due to these differences in membrane properties, the mass transfer coefficients for the MA-1 membrane are higher compared to the AMX membrane at potential drops of 1 and 2 V. Our findings suggest that the most optimal operating mode for the MA-1 membrane is at a potential drop of 1 V in the electromembrane system, which results in a specific energy consumption of 0.24 kWh/mol. Contrastingly, under comparable conditions for the AMX membrane, the specific energy consumption is 0.34 kWh/mol.

Synthesis and characterization of water-based CIGS ink for photovoltaic applications

Due to their many benefits, CIGS (Copper Indium Gallium Selenide, CuInxGa(1−x)Se2) based solar cells are preferred over their alternatives for powering different systems in space applications. The current methods for synthesizing the CIGS thin films are expensive and complicated due to the use of vacuum and/or involvement of high temperatures and a multi-step approach involving a separate selenization step. Ink-jet printing is considered as a simple and affordable process to deposite thin films, which require materials in the ink (particulate dispersion) form. Thus, the presented work focuses on synthesizing a printable CIGS ink using a solution processing route at room temperature without a vacuum environment. The synthesis of CIGS ink is done from a chemical bath containing the ions of its constituents, followed by the addition of a strong reducing agent and continuous, vigorous stirring. An analysis of X-ray diffraction verified the existence of the CIGS crystal structure. With the help of UV–visible spectroscopy, the band gap of the ink was calculated using the Tauc plot method, while morphological studies were done using FESEM and AFM. This effort will contribute to developing an easy-to-use, low-cost method for the continued development of CIGS ink.Graphical

Fabrication and characterization of PVDF/PMMA nanocomposite membranes doped with graphene oxide (GO) for separation of CO2/CH4 from flue gas

This work focuses on developing polyvinylidene fluoride/polymethyl methacrylate (PVDF/PMMA) polymer blend nanocomposites incorporating varying concentrations of graphene oxide (GO) nanoparticles fabricated via casting solution processes. XRD and FT-IR confirmed GO-induced structural modifications in PVDF/PMMA blend. The addition of GO into PMMA/PVDF blend decreased and weakened the intensity of XRD peaks, suggesting that adding GO gradually reduces the crystallinity of the films. FT-IR verified miscibility and complex formation between the pristine polymer blend and the GO-filled nanocomposite. The incorporation of GO caused shifts in the optical absorption edge to lower wavelengths, causing a decrease in the optical bandgap energy (Eg). The real and imaginary parts of the dielectric permittivity (ε′ and ε′′), electric modulus (M′, M″), and AC conductivity (σac) have been measured from 0.1 Hz to 6 MHz. Both ε′ and ε′′ declined with rising frequency. The addition of different concentrations of GO generated charge transfer complexes in the polymer nanocomposites. SEM images show good homogeny with random dispersion of GO inside the polymer blend. The thermoluminescence (TL) glow curves for the nanocomposite samples irradiated 0.5, 1.0, 1.5, and 2 Gy doses show peak cantered at 207 °C. The peak position remained unchanged with increasing irradiation dosage. The dose-dependent linear growth in maximum peak height indicates radiation detection and monitoring capability.

Numerical analysis of solute transport and longitudinal dispersion coefficients in vegetated flow

Reasonable estimates of longitudinal dispersion coefficients are essential for predicting solute dispersion processes. However, the current knowledge of solute dispersion processes in vegetated waters is limited. In this work, we coupled a refined hydrodynamic model with scalar transport equations to simulate the flow field and dispersion process of solutes in water under the effect of vegetation. First, the proposed numerical model was verified using laboratory experiments, revealing the excellent performance of the coupled model in complex conditions. Eight different cases were subsequently simulated to analyse the effects of the upstream flow rate and vegetation height on the streamwise velocity, solute concentration, and longitudinal dispersion coefficients. The simulation results show that the upstream flow variation exerts a marked effect on the streamwise velocity and flow field within the vegetation zone, with a velocity difference within the shear layer reaching 54.7 % for an upstream flow of 0.018 m3·s-1. The height of the vegetation affects both the velocity profile and solute dispersion. Placing emergent vegetation upstream can enhance solute dispersion in the longitudinal direction. The correlation analysis reveals that the longitudinal dispersion coefficients obtained using the routing producer are close to those determined using the theoretical method, with correlation coefficients reaching 0.75. This work presents the appropriate application range and parameters that must be considered in deriving formulas for longitudinal dispersion coefficients.

A Fluorescent Covalent Organic Cage for Ultrafast Detection of Picric Acid and HCl Vapor Sensing.

Covalent organic cages (COCs) have recently gained massive attention owing to their solution processability and structural flexibility. Herein, we report an amine-linked fluorescent COC (COC2) synthesized by adopting dynamic covalent imine chemistry followed by imine bond reduction and characterized with different spectroscopic techniques. The COC2 was utilized for highly sensitive and selective detection of picric acid at the nanomolar level. The fluorescence quenching efficiency of PA towards the COC2 is 98.6%, with a detection limit of 2.7 nM. PA sensing with the COC2, coated on a TLC plate and paper strip, exhibited an outstanding fluorescence quenching property. Furthermore, the COC2 unveiled solid-state acidochromism upon exposure to HCl acid fumes and was transferred back to the original form on exposure to NH3 vapours.

Method for Reconstructing Velocity Field Images of the Internal Structures of Bridges Based on Group Sparsity

Non-destructive testing (NDT) enables the determination of internal defects and flaws in concrete structures without damaging them, making it a common application in current bridge concrete inspections. However, due to the complexity of the internal structure of this type of concrete, limitations regarding measurement point placement, and the extensive detection area, accurate defect detection cannot be guaranteed. This paper proposes a method that combines the Simultaneous Algebraic Reconstruction Technique with Group Sparsity Regularization (SART-GSR) to achieve tomographic imaging of bridge concrete under sparse measurement conditions. Firstly, a mathematical model is established based on the principles of the tomographic imaging of bridge concrete; secondly, the SART algorithm is used to solve for its velocity values; thirdly, on the basis of the SART results, GSR is applied for optimized solution processing; finally, simulation experiments are conducted to verify the reconstruction effects of the SART-GSR algorithm compared with those of the SART and ART algorithms. The results show that the SART-GSR algorithm reduced the relative error to 1.5% and the root mean square error to 89.76 m/s compared to the SART and ART algorithms. This improvement in accuracy makes it valuable for the tomographic imaging of bridge concrete and provides a reference for defect detection in bridge concrete.

Fabrication of MOSCAP and VARICAP Based Soil Sensors Using Low-Cost Solution Processing

Fabrication of MOSCAP and VARICAP Based Soil Sensors Using Low-Cost Solution Processing

Fine-Tuning Conformation of PEDOT Chains Enables Simultaneously Enhanced Conductivity, Work Function, Transmittance, and Waterproofness in PEDOT:PSS Interlayer for Highly Efficient and Stable Organic Photovoltaics.

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is widely utilized as the hole transport layer (HTL) inorganic photovoltaics (OPVs) because of its low-temperature solution processing peculiarity, high optical transmittance, and excellent mechanical flexibility. However, the core-shell structure of PSS coated PEDOT results in relatively low conductivity, work function, transmittance and waterproofness of PEDOT:PSS interlayer, limiting the photovoltaic performance and stability of OPVs. Here, the conformation of PEDOT chains are regulated from helical benzoyl to linear quinone structure via incorporation of 2D Cd0.85PS3Li0.15H0.15dopant into the conventional PEDOT:PSS interlayer, promoting an interpenetrating network structure in PEDOT:PSS interlayer and forming an efficient hole transport channel from active layer to ITO electrode. Such features significantly improve the electrical conductivity, work function, and transmittance of PEDOT:PSS interlayer. In consequence, the maximum power conversion efficiency (PCE) of D18:L8-BO, PBDB-T:ITIC, as well as PTzBI-dF:L8-BO based OPVs ameliorated from 18.37%, 8.94%, and 15.80% to 19.26%, 10.00%, and 16.83%, respectively. The application of Cd0.85PS3Li0.15H0.15 doping PEDOT:PSS strategy demonstrates great potential for the development of strongly conductive, large-work-function, highly transparent, and excellent-waterproof PEDOT:PSS interlayer toward highly efficient and stable OPVs.

Green corrosion inhibitors for nickel in acidic media utilizing novel imine ligand and its Zn (II) metal chelate supported by DFT calculation

L and ZnL complex act as corrosion inhibitors were synthesized and their structural elucidation were characterized via various spectroscopic and physicochemical tools. Correlation of experimental data with DFT calculation affords that ZnL complex is octahedral. L and ZnL compounds were used as essential components and environmentally benign inhibitors to reduce the rate at which Nickel as metal and its alloys corroded. In the investigative research, 0.5 M H2SO4 was used as the corroding medium. Electrochemical impedance spectroscopy and the Tafel plot were used to analyse the electrochemical performances of L, its complex with Zn, and the inhibitory effect in the acid under test. Processes of Ni corroding in an acidic solution have been examined in relation to additive existence and deficiency. The obtained data demonstrate that while the inhibitory effect increases as the dose of the additives is increased, density of corrosion current Icorr. gradually decreases. It is noted that inhibition efficiency decreases with increasing temperature especially at high temperature (55 °C) in the case of presence of 1 × 10−3 M of L as an additive (η = 70.4 %). Although, in the case of utilizing ZnL complex as an additive, it in noted that inhibition efficiency η% is nearly the same and slightly changed with raising temperature. In the case of existence high dose of ZnL, η% slightly increases with temperature indicating chemisorption process of the additive on Ni surface in the acidic medium. When the additives are present in the solution, both the cathodic and anodic reaction processes are impacted. Furthermore, the presence of the ligand or its complex reduces the amount of NiO that forms on the electrode’s exterior sides. This finding implies that the adsorption mechanism of ZnL additive species follows Langmuir model and that kind of ligand and its complex adsorption on its outside are chemical in nature. These results have also been confirmed by electrochemical impedance spectroscopy. The ligand and its complex were included as additives, which significantly improved nickel’s corrosion resistance, according to the results. Studies on the effects of temperature have been done with different additive doses and Tafel plot method. High activation energy value of (−79.3 kJ. mol−1) was achieved when using 1 × 10−4 M of the L as well as (−82.8kJ. mol−1) in the presence of 1 × 10−3 M of ZnL in 0.5 M H2SO4. The standard enthalpy change ΔH0ads. for Ni in the acidic medium taking many dosages of L and ZnL were −31.16 and –32.72 kJ/mol, respectively. In light of this result, the adsorption process was chemisorption and the adsorption method was exothermic. Positive ΔS0ads values are correlated with an increase in solvent energy and a rise in the water desorption entropy. Employing scanning electron microscopy, the outward side morphology of the corroded samples was examined. Through a scanning electron microscope, the framework and texture of the films of oxide that are generated on Ni after potentiodynamic polarisation at different doses of ZnL additive are apparent.

Electron-Deficient Organic Molecules Based on B←N Unit: A N-Type Room-Temperature Chemiresistive Sensors with Moisture Resistance.

Organic molecules with tailorable chemical structures, high stability, and solution processability have great potential in the sensing field. Compared with p-type organic small molecules (OSMs), the electron-dominated n-type analogs show superior conductivity when exposed to reducing gases, which can achieve outstanding sensor signal-to-noise ratios. However, inadequate humidity resistance at room temperature hinders the development of such molecules. Herein, an A-D-π-D-A molecular design strategy is proposed based on electron-deficient B←N units, which results in effective intramolecular charge transport and sensitive responses by extending the π-conjugation bridge. As a result, the ST-2BP with A-D-π-D-A configuration shows a prominent sensitivity of 787 (Ra/Rg) in 20ppm NH3 at room temperature and an almost initial and stable response under different relative humidity conditions, which is the highest among currently reported OSM sensors. Supported by theoretical calculations and in situ FTIR spectra, it is revealed that B←N units, which function as the active centers mediate the specific ammonia adsorption. This study provides a new understanding of the design of high-performance room temperature gas sensing materials by decorating B←N units.