Significant improvement in thermoelectric performance of SnSe/SnS via nano-heterostructures.

In this work, we study theoretically the electronic and phonon transport properties of heterojunction SnSe/SnS, bilayer SnSe and SnS. The energy filtering effect caused by the nano heterostructure in SnSe/SnS induces an increase in the Seebeck coefficient, causing a large power factor. We calculate the phonon relaxation time and lattice thermal conductivity κL for the three structures; the heterogeneous nanostructure could effectively reduce κL due to the enhanced phonon boundary scattering at interfaces. The average κL notably reduces from around 3.3 (3.2) W m-1 K-1 for bilayer SnSe (SnS) to nearly 2.2 W m-1 K-1 for SnSe/SnS at 300 K. As a result, the average ZT (ZTave in b and c directions) reaches 1.63 with temperature range around 300-800 K, which is improved by 63% (25%) compared with that of bilayer SnSe (SnS). Our theoretical results show that the heterogeneous nanostructure is an innovative approach for improving the Seebeck coefficient and significantly reducing κL, effectively enhancing thermoelectric properties.

Realizing high thermoelectric performance with comparable p- and n-type figure-of-merits in a graphene/h-BN superlattice monolayer.

Carbon-based structures are a superior alternative for unleashing the thermoelectric potential of earth-abundant and environmentally friendly materials. Here we design a hybrid graphene/h-BN superlattice monolayer and investigate its thermoelectric properties based on density functional theory and accurate solution of Boltzmann transport equations. Compared with that of pristine graphene, the lattice thermal conductivity of the superlattice structure is more than two orders of magnitude lower ascribed to the significantly increased phonon scattering originating from the mixed-bond characteristics. Besides, the obvious valley anisotropy near the electronic band edge leads to an ultrahigh power factor along the zigzag direction, which in turn gives an n-type ZT value as high as 2.5 at 1100 K. Moreover, it is interesting to find that the thermoelectric performance of p-type system can be enhanced to be comparable with that of n-type one by appropriate substitution of the nitrogen atom with phosphorus, which can suppress the lattice thermal conductivity but nearly have no effect on the hole transport.

Destratification and oxygenation efficiency of a water-lifting aerator system in a deep reservoir: Implications for optimal operation.

Thermal stratification is a common phenomenon in lakes and reservoirs and has a significant influence on water quality dynamics. Heihe Reservoir is a canyon-shaped reservoir in Shaanxi Province with strong thermal stratification. Therefore, eight water-lifting aerators (WLAs) were installed in this reservoir, which could overcome thermal stratification and increase oxygenation with gas flows between 20 and 50m3/hr, and oxygenate the hypolimnion with gas flows less than 20m3/hr. To examine the destratification efficiency of the WLA system, we used a three-dimensional hydrodynamic module based on MIKE 3 to simulate the thermal structure of Heihe Reservoir and compared the simulations with measured data. Results showed that operation of the WLA system promoted water mixing and effectively oxygenated the hypolimnion. Through the established energy utilization assessment method, the energy utilization efficiency of the WLA system was between 5.36% and 7.30%, indicating the capability of the technique for destratification in such a large reservoir. When the surface water temperature dropped to the theoretical mixed water temperature calculated by the energy utilization assessment method, reducing gas flow could save energy. This would prevent anaerobic conditions from occurring in the bottom water and maintain good water quality in Heihe Reservoir.

Sediment pollution characteristics and in situ control in a deep drinking water reservoir.

Sediment pollution characteristics, in situ sediment release potential, and in situ inhibition of sediment release were investigated in a drinking water reservoir. Results showed that organic carbon (OC), total nitrogen (TN), and total phosphorus (TP) in sediments increased from the reservoir mouth to the main reservoir. Fraction analysis indicated that nitrogen in ion exchangeable form and NaOH-extractable P (Fe/Al-P) accounted for 43% and 26% of TN and TP in sediments of the main reservoir. The Risk Assessment Code for metal elements showed that Fe and Mn posed high to very high risk. The results of the in situ reactor experiment in the main reservoir showed the same trends as those observed in the natural state of the reservoir in 2011 and 2012; the maximum concentrations of total OC, TN, TP, Fe, and Mn reached 4.42mg/L, 3.33mg/L, 0.22mg/L, 2.56mg/L, and 0.61mg/L, respectively. An in situ sediment release inhibition technology, the water-lifting aerator, was utilized in the reservoir. The results of operating the water-lifting aerator indicated that sediment release was successfully inhibited and that OC, TN, TP, Fe, and Mn in surface sediment could be reduced by 13.25%, 15.23%, 14.10%, 5.32%, and 3.94%, respectively.

Nitrogen removal from micro-polluted reservoir water by indigenous aerobic denitrifiers.

Treatment of micro-polluted source water is receiving increasing attention because of environmental awareness on a global level. We isolated and identified aerobic denitrifying bacteria Zoogloea sp. N299, Acinetobacter sp. G107, and Acinetobacter sp. 81Y and used these to remediate samples of their native source water. We first domesticated the isolated strains in the source water, and the 48-h nitrate removal rates of strains N299, G107, and 81Y reached 33.69%, 28.28%, and 22.86%, respectively, with no nitrite accumulation. We then conducted a source-water remediation experiment and cultured the domesticated strains (each at a dry cell weight concentration of 0.4 ppm) together in a sample of source water at 20-26 °C and a dissolved oxygen concentration of 3-7 mg/L for 60 days. The nitrate concentration of the system decreased from 1.57 ± 0.02 to 0.42 ± 0.01 mg/L and that of a control system decreased from 1.63 ± 0.02 to 1.30 ± 0.01 mg/L, each with no nitrite accumulation. Total nitrogen of the bacterial system changed from 2.31 ± 0.12 to 1.09 ± 0.01 mg/L, while that of the control system changed from 2.51 ± 0.13 to 1.72 ± 0.06 mg/L. The densities of aerobic denitrification bacteria in the experimental and control systems ranged from 2.8 × 10(4) to 2 × 10(7) cfu/mL and from 7.75 × 10(3) to 5.5 × 10(5) cfu/mL, respectively. The permanganate index in the experimental and control systems decreased from 5.94 ± 0.12 to 3.10 ± 0.08 mg/L and from 6.02 ± 0.13 to 3.61 ± 0.11 mg/L, respectively, over the course of the experiment. Next, we supplemented samples of the experimental and control systems with additional bacteria or additional source water and cultivated the systems for another 35 days. The additional bacteria did little to improve the water quality. The additional source water provided supplemental carbon and brought the nitrate removal rate in the experimental system to 16.97%, while that in the control system reached only 3.01%, with no nitrite accumulation in either system. Our results show that aerobic denitrifying bacteria remain highly active after domestication and demonstrate the applicability of such organisms in the bioremediation of oligotrophic ecosystems.

Buying Game Derivative Products Is Different from In-Game Purchases: A Mixed-Method Approach.

The consumption of games has received increasing attention due to their high profits and addiction issues. However, previous studies have focused mainly on players' in-game purchases, neglecting the purchase of game derivative products. This article provides the first exploration of the differences and similarities between in-game purchases and derivative product purchases with a mixed-method approach. A quantitative survey collected data from 9864 game players, and the results suggested that there were differences between in-game purchases and derivative product consumption in terms of consumption amount and number of participants, and that derivative product purchases had a stronger relationship with character attachment and game loyalty. Subsequent interviews were conducted with 22 players. The findings supported the quantitative results and revealed that players exhibited a distinct understanding of each type of purchase in terms of ownership. Overall, these findings contribute to the understanding of game derivative product purchases and explore the factors influencing in-game purchases and derivative product purchases. We strongly argue that the pattern of spending on game derivative products is very different from that of spending on in-game purchases and is, thus, worthy of dedicated research.

LiNbO3 and LiTaO3 Coating Effects on the Interface of the LiCoO2 Cathode: A DFT Study of Li-Ion Transport.

In solid-state batteries, the interface between cathodes and solid electrolytes is crucial and coating layers play a vital role. LiNbO3 has been known as a promising coating material, whereas recent studies showed its degradation via releasing oxygen and lithium during cycling. This computational study addresses the elucidation of essential characteristics of the coating materials by examining LiNbO3 and its counterpart LiTaO3 interfaces to a representative layered cathode, LiCoO2. Employing the interface CALYPSO method, we constructed explicit models of both coatings on LiCoO2. Our findings indicate that LiTaO3 offers easier Li+ migration at the interface due to the smaller difference in Li adiabatic potential at the interface, whereas LiNbO3 more effectively suppresses oxygen activity at high delithiation states via lowering the O 2p states. This comparative analysis provides essential insights into optimizing coating materials for improved battery performance.

Distribution, risk assessment of heavy metals in sediments, and their potential risk on water supply safety of a drinking water reservoir, middle China.

Heavy metals in reservoir sediments were analyzed to assess the pollution level and to understand the potential risk on water supply safety. Heavy metals in sediments will enter the biological chain through bio-enrichment and bio-amplification in water and eventually pose a threat to the safety of drinking water supply. Analysis of eight sampling sites in JG (Jian gang) drinking water reservoir of the sediments showed that from Feb 2018 to Aug 2019 heavy metals including Pb, Ni, Cu, Zn, Mo, and Cr increased by 1.09-17.2%. Vertical distributions of heavy metals indicated that the concentrations increased gradually by 9.6-35.8%. Risk assessment code analysis indicated that Pb, Zn, and Mo were of high risk in the main reservoir area. What is more, enrichment factors of Ni and Mo were 2.76-3.81 and 5.86-9.41, respectively, showing the characteristics of exogenous input. The continuous monitoring results of the bottom water showed that the concentration of heavy metals in the bottom water exceeded the environmental quality standard value of surface water in China, and exceeded the standard by 1.76 times (Pb), 1.43 times (Zn), and 2.04 times (Mo), respectively. Heavy metals in the sediments of JG Reservoir, especially in the main reservoir area, have a potential risk of release from the sediment to the overlying water. Water supply reservoir as a source of drinking water, its quality is directly related to human health and production activities. Therefore, this first study on JG Reservoir is of great significance for the protection of drinking water safety and human health.

First-Principles Study on the Interplay of Strain and State-of-Charge with Li-Ion Diffusion in the Battery Cathode Material LiCoO2.

Cathode degradation of Li-ion batteries (Li+) continues to be a crucial issue for higher energy density. A main cause of this degradation is strain due to stress induced by structural changes according to the state-of-charge (SOC). Moreover, in solid-state batteries, a mismatch between incompatible cathode/electrolyte interfaces also generates a strain effect. In this respect, understanding the effects of the mechanical/elastic phenomena associated with SOC on the cathode performance, such as voltage and Li+ diffusion, is essential. In this work, we focused on LiCoO2 (LCO), a representative LIB cathode material, and investigated the effects of biaxial strain and hydrostatic pressure on its layered structure and Li+ transport properties through first-principles calculations. With the nudged elastic band technique and molecular dynamics, we demonstrated that in Li-deficient LCO, compressive biaxial strain increases the Li+ diffusivity, whereas tensile biaxial strain and hydrostatic pressure tend to suppress it. Structural parameter analysis revealed the key correlation of "Co layer distances" with Li+ diffusion instead of "Li layer distances", as ordinarily expected. Structural analysis further revealed the interplay between the Li-Li Coulomb interaction, SOC, and Li+ diffusion in LCO. The activation volume of LCO under hydrostatic pressure was reported for the first time. Moreover, vacancy formation energy calculations showed that the Li intercalation potential could be decreased under compressive biaxial strain due to the weakening of the Li-O bond interaction. The present findings may serve to improve the control of the energy density performance of layered cathode materials.

Symmetry-Guaranteed High Carrier Mobility in Quasi-2D Thermoelectric Semiconductors.

Quasi-2D semiconductors have garnered immense research interest for next-generation electronics and thermoelectrics due to their unique structural, mechanical, and transport properties. However, most quasi-2D semiconductors experimentally synthesized so far have relatively low carrier mobility, preventing the achievement of exceptional power output. To break through this obstacle, a route is proposed based on the crystal symmetry arguments to facilitate the charge transport of quasi-2D semiconductors, in which the horizontal mirror symmetry is found to vanish the electron-phonon coupling strength mediated by phonons with purely out-of-plane vibrational vectors. This is demonstrated in ZrBeSi-type quasi-2D systems, where the representative sample Ba1.01 AgSb shows a high room-temperature hole mobility of 344 cm2 V-1 S-1 , a record value among quasi-2D polycrystalline thermoelectrics. Accompanied by intrinsically low thermal conductivity, an excellent p-type zT of ≈1.3 is reached at 1012 K, which is the highest value in ZrBeSi-type compounds. This work uncovers the relation between electron-phonon coupling and crystal symmetry in quasi-2D systems, which broadens the horizon to develop high mobility semiconductors for electronic and energy conversion applications.

Large Magneto-Transverse and Longitudinal Thermoelectric Effects in the Magnetic Weyl Semimetal TbPtBi.

Magnetic topological semimetals provide new opportunities for power generation and solid-state cooling based on thermoelectric (TE) effect. The interplay between magnetism and nontrivial band topology prompts the magnetic topological semimetals to yield strong transverse TE effect, while the longitudinal TE performance is usually poor. Herein, it is demonstrated that the magnetic Weyl semimetal TbPtBi has high value for both transverse and longitudinal thermopower with large power factor (PF). At 300 K and 13.5 Tesla, the transverse thermopower and PF reach up to 214 µV K-1 and 35 µW cm-1  K-2 , respectively, which are comparable to those of state-of-the-art TE materials. Combining first-principles calculations, longitudinal magnetoresistance and planar Hall resistance measurements, and two-band model fitting, the large transverse thermopower and PF are attributed to both bipolar effect and large Hall angle. Moreover, the imperfectly compensated charge carriers and large transverse magnetoresistance induce the maximum magneto-longitudinal thermopower of 251 µV K-1 with a PF of 24 µW cm-1  K-2 at 150 K and 13.5 Tesla, which is two times higher than that at zero magnetic field. This work demonstrates the great potential of topological semimetals for TEs and offers a new excellent candidate for magneto-TEs.

Evaluation of the tumoricidal efficacy of adoptive cell transfer using hepatocellular carcinoma-derived organoids.

Background: Tumor-derived organoid, namely tumoroid, can realistically retain the clinicopathologic features of original tumors even after long-term in vitro expansion. Here we develop this production methodology derived from hepatocellular carcinoma primary samples and generate a platform to evaluate the tumoricidal efficacy of autologous adoptive cell transfer including tumor infiltrating lymphocytes and peripheral blood lymphocytes. Methods: Haematoxylin and eosin together with immunohistochemistry staining were employed to ascertain the morphologic and histological features of tumoroids and original tumors. Tumor killing ability of T cells was detected by lactate dehydrogenase assay and propidium iodide staining. In tumoroid xenograft mouse model, tumor volumes were measured and T cell functions were examined by flow cytometry technique. Results: Four tumoroids with characteristics of poor differentiation and mild fibrosis were successfully established from fourteen hepatocellular carcinoma samples. More robust antitumor potential and hyper-functional phenotype of all four tumor infiltrating lymphocytes were observed compared to matched peripheral blood lymphocytes in coculture system. In tumoroid xenograft mouse models, however, only one patient-derived tumor infiltrating lymphocytes with the highest antitumor activity can bestow efficient tumor eradication. Conclusions: Hepatocellular carcinoma tumoroid-based models could represent invaluable resources for evaluating the tumoricidal efficacy of autologous adoptive cell transfer. Tumor infiltrating lymphocytes should be a promising and yet-to-be-developed regimen to treat hepatocellular carcinoma.

Tuning the Electronic, Ion Transport, and Stability Properties of Li-rich Manganese-based Oxide Materials with Oxide Perovskite Coatings: A First-Principles Computational Study.

Lithium-rich manganese-based oxides (LRMO) are regarded as promising cathode materials for powering electric applications due to their high capacity (250 mAh g-1) and energy density (∼900 Wh kg-1). However, poor cycle stability and capacity fading have impeded the commercialization of this family of materials as battery components. Surface modification based on coating has proven successful in mitigating some of these problems, but a microscopic understanding of how such improvements are attained is still lacking, thus impeding systematic and rational design of LRMO-based cathodes. In this work, first-principles density functional theory (DFT) calculations are carried out to fill out such a knowledge gap and to propose a promising LRMO-coating material. It is found that SrTiO3 (STO), an archetypal and highly stable oxide perovskite, represents an excellent coating material for Li1.2Ni0.2Mn0.6O2 (LNMO), a prototypical member of the LRMO family. An accomplished atomistic model is constructed to theoretically estimate the structural, electronic, oxygen vacancy formation energy, and lithium-transport properties of the LNMO/STO interface system, thus providing insightful comparisons with the two integrating bulk materials. It is found that (i) electronic transport in the LNMO cathode is enhanced due to partial closure of the LNMO band gap (∼0.4 eV) and (ii) the lithium ions can easily diffuse near the LNMO/STO interface and within STO due to the small size of the involved ion-hopping energy barriers. Furthermore, the formation energy of oxygen vacancies notably increases close to the LNMO/STO interface, thus indicating a reduction in oxygen loss at the cathode surface and a potential inhibition of undesirable structural phase transitions. This theoretical work therefore opens up new routes for the practical improvement of cost-affordable lithium-rich cathode materials based on highly stable oxide perovskite coatings.

Anomalous Thermoelectric Performance in Asymmetric Dirac Semimetal BaAgBi.

Multiple-band degeneracy has been widely recognized to be beneficial for high thermoelectric performance. Here, we discover that the p-type Dirac bands with lower degeneracy synergistically produce a higher Seebeck coefficient and electrical conductivity in topological semimetal BaAgBi. The anomalous transport phenomenon intrinsically originated from the asymmetric electronic structures: (i) complete p-type Dirac bands near the Fermi level facilitate high and strong energy-dependent hole relaxation time; (ii) the presence of additional parabolic conduction valleys allows for a large density of states to accept scattered electrons, leading to an enlarged hole-electron relaxation time ratio and, thus, weakened bipolar effect. In combination with the strong lattice anharmonicity, an exceptional p-type average ZT of 0.42 is achieved from 300 to 600 K, which can be dramatically enhanced to 1.38 via breaking the C3v symmetry. This work uncovers the underlying mechanisms governing the abnormal transport behavior in Dirac semimetal BaAgBi and highlights the asymmetric electronic structures as target features to discover/design high-performance thermoelectric materials.

Revealing the anisotropic phonon behaviours of layered SnS by angle/temperature-dependent Raman spectroscopy.

Tin sulfide (SnS), a IV-VI group layered compound, has attracted much attention because of its excellent thermoelectric properties along the crystallographic b-axis. However, there are few reports on the identification of its in-plane orientation. We observe a strong anisotropy of the in-plane Raman signal in bulk SnS. With the help of ab initio calculations, the vibrational symmetry of each observed Raman mode in the cleaved (00l)-plane is consistent with the experimental values. The angle-resolved polarized Raman spectroscopy, combined with electron backscattered diffraction technology, is utilized to systematically investigate the in-plane anisotropy of the phonon response and then determine the in-plane orientation. Furthermore, the temperature-dependent and laser-power-dependent Raman scattering analyses reveal that the adjacent layers in the SnS crystals show a relatively weak van der Waals interaction. These findings could provide much-needed experimental information for future applications related to the anisotropic transport properties of SnS single crystals.

Prognostic Significance of Cuproptosis-Related Gene Signatures in Breast Cancer Based on Transcriptomic Data Analysis.

Breast cancer (BRCA) remains a serious threat to women's health, with the rapidly increasing morbidity and mortality being possibly due to a lack of a sophisticated classification system. To date, no reliable biomarker is available to predict prognosis. Cuproptosis has been recently identified as a new form of programmed cell death, characterized by the accumulation of copper in cells. However, little is known about the role of cuproptosis in breast cancer. In this study, a cuproptosis-related genes (CRGs) risk model was constructed, based on transcriptomic data with corresponding clinical information relating to breast cancer obtained from both the TCGA and GEO databases, to assess the prognosis of breast cancer by comprehensive bioinformatics analyses. The CRGs risk model was constructed and validated based on the expression of four genes (NLRP3, LIPT1, PDHA1 and DLST). BRCA patients were then divided into two subtypes according to the CRGs risk model. Furthermore, our analyses revealed that the application of this risk model was significantly associated with clinical outcome, immune infiltrates and tumor mutation burden (TMB) in breast cancer patients. Additionally, a new clinical nomogram model based on risk score was established and showed great performance in overall survival (OS) prediction, confirming the potential clinical significance of the CRGs risk model. Collectively, our findings revealed that the CRGs risk model can be a useful tool to stratify subtypes and that the cuproptosis-related signature plays an important role in predicting prognosis in BRCA patients.

In-situ micro-Raman study of SnSe single crystals under atmosphere: Effect of laser power and temperature.

Single crystal of tin selenide (SnSe) was studied by micro-Raman spectroscopy under atmosphere conditions. The effect of varying the incident laser power on the sample up to 2 mW was analyzed. The Raman spectra showed that the number of all vibrational modes have not decreased or increased, but all peaks red-shifted and softened obviously as the laser power increased to the threshold value. The temperature-dependent micro-Raman study of the single crystal was carried out for illustrating thermal effect due to the high incident laser power. A new SnSe2 phase appeared at high temperature without vacuum and become the dominant phase at the surface of the crystal gradually because of oxidation. Detecting few amounts of SnSe2 crystals on the surface of single crystal shows the high sensitivity of Raman spectroscopy. High resolution transmission electron microscopy (HRTEM) was also used to confirm that the newly generated SnSe2 phase is precipitated by SnSe under high temperature oxidation conditions. To study the Raman spectra of low thermal conductivity materials under high temperature and non-vacuum conditions, lower incident laser power should be used to avoid the influence of additional thermal effects.

Unconventional Doping Effect Leads to Ultrahigh Average Thermoelectric Power Factor in Cu3 SbSe4 -Based Composites.

Thermoelectric materials are typically highly degenerate semiconductors, which require high carrier concentration. However, the efficiency of conventional doping by replacing host atoms with alien ones is restricted by solubility limit, and, more unfavorably, such a doping method is likely to cause strong charge-carrier scattering at ambient temperature, leading to deteriorated electrical performance. Here, an unconventional doping strategy is proposed, where a small trace of alien atoms is used to stabilize cation vacancies in Cu3 SbSe4  by compositing with CuAlSe2 , in which the cation vacancies rather than the alien atoms provide a high density of holes. Consequently, the hole concentration enlarges by six times but the carrier mobility is well maintained. As a result, a record-high average power factor of 19 µW cm-1  K-2  in the temperature range of 300-723 K is attained. Finally, with further reduced lattice thermal conductivity, a peak zT value of 1.4 and a record-high average zT value of 0.72 are achieved within the diamond-like compounds. This new doping strategy not only can be applied for boosting the average power factor for thermoelectrics, but more generally can be used to maintain carrier mobility for a variety of semiconductors that need high carrier concentration.

Hydrazine Hydrate Intercalated 1T-Dominant MoS2 with Superior Ambient Stability for Highly Efficient Electrocatalytic Applications.

Metallic 1T-phase MoS2 exhibits superior hydrogen evolution reaction (HER) performance than natural 2H-phase MoS2 owing to its higher electrical conductivity and abundance of active sites. However, the reported 1T-MoS2 catalysts usually suffer from extreme instability, which results in quick phase transformation at ambient conditions. Herein, we present a facile approach to engineer the phase of MoS2 by introducing intercalated hydrazine. Interestingly, the as-synthesized 1T-dominant MoS2 sample demonstrates excellent ambient stability without noticeable degradation for 3 months. Additionally, the 1T-dominant MoS2 exhibits superior electrical conductivity (∼700 times higher than that of 2H-MoS2) and improved electrochemical catalytic performance (current density ∼12 times larger than that of 2H-MoS2 at an overpotential of 300 mV vs the reversible hydrogen electrode, RHE). Through experimental characterizations and density functional theory (DFT) calculation, we conclude that the stabilization of the metallic phase could be attributed to the electron donation from hydrazine molecules to the adjacent Mo atoms. The phase control strategy in this work provides a guideline to develop other highly efficient and stable two-dimensional (2D) electrocatalysts.

Quantum Dot Passivation of Halide Perovskite Films with Reduced Defects, Suppressed Phase Segregation, and Enhanced Stability.

Structural defects are ubiquitous for polycrystalline perovskite films, compromising device performance and stability. Herein, a universal method is developed to overcome this issue by incorporating halide perovskite quantum dots (QDs) into perovskite polycrystalline films. CsPbBr3 QDs are deposited on four types of halide perovskite films (CsPbBr3 , CsPbIBr2 , CsPbBrI2 , and MAPbI3 ) and the interactions are triggered by annealing. The ions in the CsPbBr3 QDs are released into the thin films to passivate defects, and concurrently the hydrophobic ligands of QDs self-assemble on the film surfaces and grain boundaries to reduce the defect density and enhance the film stability. For all QD-treated films, PL emission intensity and carrier lifetime are significantly improved, and surface morphology and composition uniformity are also optimized. Furthermore, after the QD treatment, light-induced phase segregation and degradation in mixed-halide perovskite films are suppressed, and the efficiency of mixed-halide CsPbIBr2 solar cells is remarkably improved to over 11% from 8.7%. Overall, this work provides a general approach to achieving high-quality halide perovskite films with suppressed phase segregation, reduced defects, and enhanced stability for optoelectronic applications.