Engineering High-Performance Hypergolic Propellant by Synergistic Contribution of Metal-Organic Framework Shell and Aluminum Core.

Hypergolicity is a highly desired characteristic for hybrid rocket engine-based fuels because it eliminates the need for a separate ignition system. Introducing hypergolic additives into conventional fuels through physical mixing is a feasible approach, but achieving highly reliable hypergolic ignition and energy release remains a major challenge. Here, the construction of core-shell Al@metal organic framework (MOF) heterostructures is reported as high-performance solid hypergolic propellants. Upon contact with the liquid oxidizer the uniformly distributed hypergolic MOF (Ag-MOF) shell can induce the ignition of hypergolic-inert fuel Al, resulting in Al combustion. Such a synthetic strategy is demonstrated to be favorable in hotspot generation and heat transfer relative to a simple physical mixture of Al/Ag-MOF, thus producing shorter ignition delay times and more efficient combustion. Thermal reactivity study indicated that the functionalization of the Ag-MOF shell changes the energy release process of the inner Al, which is accompanied by a thermite reaction. The synergistic effect of implantation of hypergolic MOF and high energy Al contributes to high specific impulses of 230-270 s over a wide range of oxidizer-to-fuel ratios.

Introducing Carborane Clusters into Crystalline Frameworks via Thiol-Yne Click Chemistry for Energetic Materials.

Crystalline frameworks represent a cutting-edge frontier in material science, and recently, there has been a surge of interest in energetic crystalline frameworks. However, the well-established porosity often leads to diminished output energy, necessitating a novel approach for performance enhancement. Thiol-yne coupling, a versatile metal-free click reaction, has been underutilized in crystalline frameworks. As a proof of concept, we herein demonstrate the potential of this approach by introducing the energy-rich, size-matched, and reductive 1,2-dicarbadodecaborane-1-thiol (CB-SH) into an acetylene-functionalized framework, Zn(AIm)2, via thiol-yne click reaction. This innovative decoration strategy resulted in a remarkable 46.6 % increase in energy density, a six-fold reduction in ignition delay time (4 ms) with red fuming nitric acid as the oxidizer, and impressive enhancement of stability. Density functional theory calculations were employed to elucidate the mechanism by which CB-SH promotes hypergolic ignition. The thiol-yne click modification strategy presented here permits engineering of crystalline frameworks for the design of advanced energetic materials.

Constructing Highly Reliable and Adaptive Primary Explosive Composites for Micro-Initiator Assisting by a Hybrid Template of Metal-Organic Frameworks and Cross-Linked Polymers.

Primary explosive, as a reliable initiator for secondary explosives, is the central component of micro-initiators for modern aerospace systems and military operations. However, they are typically prepared as powders, posing potential safety risks because of the inevitable particles scattering issues in the actual working environments. Here, the fabrication of a highly adaptive bulk material of copper azide (CA)-based safe primary explosive for micro-initiators is demonstrated. This bulk material, as derived by a complete azidation reaction of the carbonized metal-organic framework/cross-linked polymer hybrid template, enables the firm embedding of active CA species in a cross-linked carbon network (denoted as CA-C). Interestingly, this CA-C bulk material demonstrates multifarious mechanical stabilities (e.g., good shock and vibration resistance, and anti-overload capacity) in the simulated working conditions. Meanwhile, the CA contents in the CA-C bulk material reached as high as 70.3%, ensuring its detonation power. As a proof of concept, CA-C bulk material assembling in a micro-detonator can efficiently detonate the secondary explosive of CL-20 under laser irradiation. This work hereby advances the fabrication of safe and powerful primary explosives for the fulfillment of safe micro-initiator in a broad range of applications in aerospace systems.

Theoretical investigation of the magnetic and optical properties in a transition metal-doped GaTeCl monolayer.

We investigate the structural, magnetic, electronic and optical properties of a transition metal-doped GaTeCl monolayer, denoted as M@GaTeCl (M = V, Cr, Mn, Fe and Co), by using first-principles calculations. It is found that the magnetic ground state can be regulated by different M elements. In the meantime, the electronic structure is different with the doping of different M metal atoms, and thus the optical absorption changes correspondingly. The electronic calculations of M@GaTeCl suggest that V@GaTeCl, Cr@GaTeCl, Mn@GaTeCl and Fe@GaTeCl are semiconductors and the magnetic ground states are G-type antiferromagnetic (AFM), C-type AFM, A-type AFM and C-type AFM order, respectively, while Co@GaTeCl is a metal and the ground state is ferromagnetic (FM) order. The different magnetic ground states are discussed with the Heisenberg model. The rough estimation of the ferroelectric polarization value of M@GaTeCl suggests that M@GaTeCl still exhibits multiferroicity. The electronic structure is explained by the projected density of states, band structure and decomposed charge of the valence band maximum (VBM) and conduction band minimum (CBM). Simultaneously, the absorption coefficient calculations indicate that M@GaTeCl absorption shows anisotropic properties, as the same as in a pure GaTeCl monolayer, there exists enhanced visible light absorption in these M@GaTeCl monolayers relative to the pure GaTeCl one, which can be interpreted by the anisotropic structure and by the peculiar electronic structure. Thus, we found that the magnetic ground state, the electronic structure, and the absorption coefficient of M@GaTeCl can be tuned by doping different transition metal M atoms, and the ferroelectricity is still retained, which makes M@GaTeCl a potential multifunctional material in spintronics and optics.

Cooperative Catalysis between Dual Copper Centers in a Metal-Organic Framework for Efficient Detoxification of Chemical Warfare Agent Simulants.

Chemical warfare agents (CWAs) are among the most lethal chemicals known to humans. Thus, developing multifunctional catalysts for highly efficient detoxification of various CWAs is of great importance. In this work, we developed a robust copper tetrazolate metal-organic framework (MOF) catalyst containing a dicopper unit similar to the coordination geometry of the active sites of natural phosphatase and tyrosinase enzymes. This catalyst aided in phosphate ester bond hydrolysis and hydrogen peroxide decomposition, ultimately achieving high detoxification efficiency against both a nerve agent simulant (diethoxy-phosphoryl cyanide (DECP)) with a half-life of 3.5 min and a sulfur mustard simulant (2-chloroethyl ethyl sulfide (CEES)) with a half-life of 4.5 min, making it competitive with other reported materials. The dicopper sites in ZZU-282 provide versatile binding modes with the substrates, thereby promoting the activation of substrates and enhancing the catalytic efficiency. A combination of postmodified metal exchange control experiments, density functional theory calculations, and catalytic evaluations confirmed that dual Cu sites are the active centers promoting the catalytic reaction. This study offers a new design perspective to achieve advanced catalysts for CWA detoxification.

Endoscopic radiofrequency ablation may improve overall survival in patients with inoperable ampullary carcinoma.

OBJECTIVES: Patients with advanced ampullary carcinoma (AC) who are unsuitable for surgery are most likely to have poor outcomes. The role of endoscopic radiofrequency ablation (RFA) in this population has not been fully defined. We aimed to assess the short- and long-term outcomes of RFA in a large cohort of AC patients. METHODS: In this retrospective study, data of consecutive patients with pathologically proven AC who underwent successful endobiliary RFA and/or stent placement were collected. All patients did not undergo surgical resection. The primary outcome was overall survival (OS). The secondary outcomes included clinical success and adverse events. RESULTS: A total of 85 patients, 50 in the RFA plus stenting group and 35 in the stenting alone group, were identified. The median OS was significantly longer in the RFA group than in the stenting alone group (16.9 vs. 9.8 months, P < 0.001). In multivariable Cox analysis, RFA (hazards ratio 0.408; 95% confidence interval 0.235-0.706; P = 0.001) was the only independent OS predictor. Eight patients with stage II tumors, exclusively from the RFA group, survived for more than 3 years. Clinical success was comparable between the two groups (96% vs. 100%, P = 0.231). Early adverse events between the two groups were similar (10% vs. 2.9%, P = 0.206); however, late biliary/pancreatic stenoses occurred in three RFA patients who were successfully managed with endoscopic interventions. CONCLUSIONS: Endoscopic RFA appears to prolong patients' survival with acceptable safety; it may therefore be a feasible treatment option for patients with inoperable ampullary cancers.

A Solvent-Mediated Excited-State Intermolecular Proton Transfer Fluorescent Probe for Fe3+ Sensing and Cell Imaging.

Constructing excited-state intermolecular proton transfer (ESIPT-e) fluorophores represents significant challenges due to the harsh requirement of bearing a proton donor-acceptor (D-A) system and their matching proton donating-accepting ability in the same molecule. Herein, we synthesized a new-type ESIPT-e fluorophor (2-APC) using the "four-component one-pot" reaction. By the installing of a cyano-group on pyridine scaffold, the proton donating ability of -NH2 was greatly enhanced, enabling 2-APC to undergo ESIPT-e process. Surprisingly, 2-APC exhibited dual-emissions in protic solvents ethanol and normal fluorescence in aprotic solvents, which is vastly different from that of conventional ESIPT-a dyes. The ESIPT emission can be obviously suppressed by Fe3+ due to the coordination reaction of Fe3+ with the A-D system in 2-APC. From this basis, a highly sensitive and selective method was established using 2-APC as a fluorescent probe, which offers the sensitive detection of Fe3+ ranging from 0 to 13 µM with the detection limit of 7.5 nM. The recovery study of spiked Fe3+ measured by the probe showed satisfactory results (97.2103.4%) with the reasonable RSD ranging from 3.1 to 3.8%. Moreover, 2-APC can also exhibit aggregation-induced effect in poor solvent or solid-state, eliciting strong red fluorescence. 2-APC was also applied to cell-imaging, exhibiting good cell-permeability, biocompatibility and color rendering. This multi-mode emission of 2-APC is significant departure from that of conventional extended p-conjugated systems and ESIPT dyes based on a flat and rigid molecular design. The "one-pot synthesis" strategy for the construction of ESIPT molecules pioneered a new route to achieve tricolor-emissive fluorophores.

Partnered Excited-State Intermolecular Proton Transfer Fluorescence (P-ESIPT) Signaling for Nitrate Sensing and High-Resolution Cell-Imaging.

Nitrite (NO2-) is a common pollutant and is widely present in the environment and in human bodies. The development of a rapid and accurate method for NO2- detection is always a very important task. Herein, we synthesized a partnered excited-state intermolecular proton transfer (ESIPT) fluorophore using the "multi-component one pot" method, and used this as a probe (ESIPT-F) for sensing NO2-. ESIPT-F exhibited bimodal emission in different solvents because of the solvent-mediated ESIPT reaction. The addition of NO2- caused an obvious change in colors and tautomeric fluorescence due to the graft of NO2- into the ESIPT-F molecules. From this basis, highly sensitive and selective analysis of NO2- was developed using tautomeric emission signaling, achieving sensitive detection of NO2- in the concentration range of 0~45 mM with a detection limit of 12.5 nM. More importantly, ESIPT-F showed the ability to anchor proteins and resulted in a recognition-driven "on-off" ESIPT process, enabling it to become a powerful tool for fluorescence imaging of proteins or protein-based subcellular organelles. MTT experimental results revealed that ESIPT-F is low cytotoxic and has good membrane permeability to cells. Thus, ESIPT-F was further employed to image the tunneling nanotube in vitro HEC-1A cells, displaying high-resolution performance.

Aminal-Linked Porphyrinic Covalent Organic Framework for Rapid Photocatalytic Decontamination of Mustard-Gas Simulant.

Covalent organic frameworks (COFs) are appealing photocatalysts for toxic chemical degradation. Great efforts have been devoted to regulate the photocatalytic performance of COFs by tuning their organic building blocks, but the relationship between COF linkage and photochemical properties has rarely been explored. Herein, we report the synthesis and characterisation of a novel aminal-linked porphyrinic COF, namely Por-Aminal-COF. Por-Aminal-COF (0.25 mol %) showed excellent photocatalytic activity toward the detoxification of the sulfur mustard simulant with a half-life (t1/2 ) of 5 min, which is far lower than that of traditional imine-linked Por-COF (t1/2 =16 min). Transient absorption spectroscopy indicated that the aminal linkages of Por-Aminal-COF facilitated the intersystem crossing process. Thus, Por-Aminal-COF showed higher triplet-state generation efficiency compared with Por-COF, consequently promoting the activation of oxygen molecular to singlet oxygen.

Electropolymerization of Metal Clusters Establishing a Versatile Platform for Enhanced Catalysis Performance.

Atomically precise metal clusters are attractive as highly efficient catalysts, but suffer from continuous efficiency deactivation in the catalytic process. Here, we report the development of an efficient strategy that enhances catalytic performance by electropolymerization (EP) of metal clusters into hybrid materials. Based on carbazole ligand protection, three polymerized metal-cluster hybrid materials, namely Poly-Cu14 cba, Poly-Cu6 Au6 cbz and Poly-Cu6 Ag4 cbz, were prepared. Compared with isolated metal clusters, metal clusters immobilizing on a biscarbazole network after EP significantly improved their electron-transfer ability and long-term recyclability, resulting in higher catalytic performance. As a proof-of-concept, Poly-Cu14 cba was evaluated as an electrocatalyst for reducing nitrate (NO3 - ) to ammonia (NH3 ), which exhibited ≈4-fold NH3 yield rate and ≈2-fold Faraday efficiency enhancement compared to that of Cu14 cba with good durability. Similarly, Poly-Cu6 Au6 cbz showed 10 times higher photocatalytic efficiency towards chemical warfare simulants degradation than the cluster counterpart.

Ozone Decomposition by a Manganese-Organic Framework over the Entire Humidity Range.

Ground-level ozone (O3) is one of the main airborne pollutants detrimental to human health and ecosystems. However, the designed synthesis of high-performance O3 elimination catalysts suitable for broadly variable air compositions, especially a variable water vapor content, remains daunting. Herein, we report a new manganese-based metal organic framework, [Mn3(µ3-OH)2(TTPE)(H2O)4]·2H2O (H4TTPE = 1,1,2,2-tetrakis(4-(2H-tetrazol-5-yl)phenyl) ethane), denoted as ZZU-281. ZZU-281 catalyzes O3 decomposition with a nearly constant 100% working efficiency over the entire humidity range from dry (≤5% relative humidity (RH)) to high humidity (90% RH). We found that the maintainable coordinated water molecules and OH groups are activated by Mn2+, becoming active sites for O3 transfer to O2 with a low activation energy. The unique open channels, water retainability, and water stability of ZZU-281 further support the high catalytic performance. This work opens a new avenue for designing efficient catalysts for O3 elimination in practice.

A solvent-assisted ESIPT fluorescent dye for F-/Ag+ sensing and high-resolution imaging of the cilia in live cells.

A solvent-assisted ESIPT fluorescent dye was synthesized and used as a probe (2-PPN) for the detection of F-/Ag+ and high-resolution imaging of the cilia in live cells. The developed ESIPT fluorophore exhibited strong tautomeric fluorescence in protic solvents and normal emission in aprotic solvents, which is a significant departure from that of conventional intramolecular ESIPT compounds. The H-binding interaction of F- and the chelation of Ag+ with the ESIPT module of 2-PPN resulted in significant tautomeric emission quenching. From this basis, the 2-PPN-based assays for the detection of F- and Ag+ were established. The detection limit for F- and Ag+ sensing is 2.4 nM and 1.5 nM, respectively. The selective experimental results showed that no tautomeric fluorescence change of 2-PPN could be observed in the presence of the other inorganic ions in the same medium, revealing high selectivity of 2-PPN to F- and Ag+. Furthermore, MTT assay experiments proved that the probe 2-PPN exhibited low cytotoxicity and good cell membrane permeability. The probe was also further successfully utilized to image the cilia in vitro MCF7 cells, displaying its high-resolution imaging performance.Graphical abstract.

Identification of important genes and drug repurposing based on clinical-centered analysis across human cancers.

Identification of the functional impact of mutated and altered genes in cancer is critical for implementing precision oncology and drug repurposing. In recent years, the emergence of multiomics data from large, well-characterized patient cohorts has provided us with an unprecedented opportunity to address this problem. In this study, we investigated survival-associated genes across 26 cancer types and found that these genes tended to be hub genes and had higher K-core values in biological networks. Moreover, the genes associated with adverse outcomes were mainly enriched in pathways related to genetic information processing and cellular processes, while the genes with favorable outcomes were enriched in metabolism and immune regulation pathways. We proposed using the number of survival-related neighbors to assess the impact of mutations. In addition, by integrating other databases including the Human Protein Atlas and the DrugBank database, we predicted novel targets and anticancer drugs using the drug repurposing strategy. Our results illustrated the significance of multidimensional analysis of clinical data in important gene identification and drug development.

Postoperative adjuvant transcatheter arterial chemoembolization improves the prognosis of patients with huge hepatocellular carcinoma.

BACKGROUND: Surgical resection of huge hepatocellular carcinoma (HCC, ≥ 10 cm) is potentially curative. More adjuvant treatments are needed to reduce relapses in these patients. We evaluated the influence of postoperative adjuvant transcatheter arterial chemoembolization (PA-TACE) on the prognosis of huge HCC. METHODS: Data from consecutive patients who underwent curative resection for huge HCC in our center were retrospectively collected. Recurrence-free survival (RFS) and overall survival (OS) were compared between patients who did and did not undergo PA-TACE. Propensity score matching (PSM) was used. RESULTS: Among the 255 enrolled patients, 93 underwent PA-TACE. The clinical outcomes were significantly better in the PA-TACE group than those in the non PA-TACE group (5-year RFS rate: 33.5% vs. 18.0%; 5-year OS rate: 47.0% vs. 28.0%, all P < 0.001). After PSM, similar results were obtained (5-year RFS rate: 28.8% vs. 17.6%, P < 0.001; 5-year OS rate: 42.5% vs. 25.0%, P = 0.004). PA-TACE decreased the possibility of early recurrence (< 2 years, crude cohort: P < 0.001, PSM cohort: P < 0.001) but not late recurrence (≥ 2 years, crude cohort: P = 0.692, PSM cohort: P = 0.325). Multivariable Cox regression analysis suggested that PA-TACE was an independent protective factor prolonging early RFS, RFS and OS. CONCLUSIONS: PA-TACE is a safe intervention for huge HCC patients after liver resection and improves outcomes.

o-Carborane-Based and Atomically Precise Metal Clusters as Hypergolic Materials.

Atomically precise o-carboranealkynyl-protected clusters [Ag14(C4B10H11)12(CH3CN)2]·2NO3 (CBA-Ag) and [Cu6Ag8(C4B10H11)12Cl]NO3 (CBA-CuAg) have been found to exhibit hypergolic activity, such that they are capable of spontaneous ignition and combustion upon contact with the white fuming nitric acid oxidizer. In particular, CBA-CuAg has a short ignition delay time of 15 ms, whereas the o-carboranealkynyl ligand is hypergolically inert. Systematic investigation revealed that the metal cluster core catalyzed the hypergolic behavior of inert o-carboranealkynyl ligand, and Cu doping further accelerated combustion catalysis. This work provides a new prospective in the rational design of novel metal cluster-based hypergolic fuels for propellant application.

Porphyrinic Silver Cluster Assembled Material for Simultaneous Capture and Photocatalysis of Mustard-Gas Simulant.

Silver cluster-assembled materials (SCAMs), by virtue of their tunable structure, accessible surface area and excellent stability, hold great promise as highly efficient catalysts. Herein, we report a new SCAM [Ag12(StBu)6(CF3COO)3(TPyP)]n (denoted as Ag12TPyP) composed of a Ag12 chalcogenolate cluster core stabilized by porphyrinic ligands. Ag12TPyP showed superior sulfur mustard simulant (2-chloroethyl ethyl sulfide, CEES) degradation efficiency and achieved a half lifetime (t1/2) of 1.5 min with 100% selectivity. The experimental results demonstrated that synergistic effects between the silver cluster and photosensitizer ligand promote the efficiency of the generation of singlet oxygen (1O2), which accelerates the decontamination rate. Additionally, benefiting from strong affinity between the silver cluster and CEES, Ag12TPyP exhibits a CEES uptake of 74.2 mg g-1. This work demonstrates that SCAMs offer a new route to the rational design of novel materials for the detoxification of mustard gas.

Steroid-responsive atypical marginal zone hyperplasia of the lip in a child.

Atypical marginal zone hyperplasia (AMZH) is a recently described disease entity seen mainly in children. AMZH most commonly affects tonsils and appendices. Cutaneous AMZH is rare. The authors report here a recurrent AMZH in the lip of a 9-year-old child who presented originally with a lip swelling for approximately 3 months. The lip lesion recurred after each incomplete excision for 4 times. Pathologically, the lesion demonstrated marginal zone B-cell hyperplasia with kappa monoclonality by flow cytometry and immunohistochemistry studies. Lymphoepithelial lesions were noted with involvement of minor salivary glands. Polymerase chain reaction for immunoglobulin heavy-chain gene rearrangement has been repeatedly negative. Polymerase chain reaction for Borrelia species DNA was negative on both paraffin-embedded tissue and plasma. Serum antibodies IgG and IgM for Helicobacter Pylori were positive. A diagnosis of AMZH was made. Two courses of anti H. Pylori therapy did not improve the lip lesion, which completely regressed after a course of prednisone therapy. With differential diagnosis of cutaneous marginal zone lymphoma, the case illustrated diagnostic challenges, especially with recurrent lesions. This is the first case of recurrent cutaneous AMZH that has uncharacteristic kappa light-chain restriction. AMZH should be considered in children with mucocutaneous lesions with features of marginal zone lymphoma.

Dyserythropoiesis in a child with pyruvate kinase deficiency and coexistent unilateral multicystic dysplastic kidney.

Pyruvate kinase (PK) deficiency is the commonest enzyme deficiency in the glycolytic pathway leading to hemolytic anemia secondary to decreased Adenosine Triphosphate (ATP) synthesis in the red cells. synthesis. PK deficiency due to mutations in the PKLR (1q21) gene leads to highly variable clinical presentation ranging from severe fetal anemia to well compensated anemia in adults. We describe dyserythropoiesis in the bone marrow of a child with transfusion dependent anemia and unilateral multicystic dysplastic kidney (MCDK) mimicking Congenital Dyserythropoietic Anemia type I (CDA type I). Persistently low erythrocyte PK levels and double heterozygous mutations present in the PKLR gene confirmed the diagnosis of PK deficiency.

Pathologic assessment of hepatocellular carcinoma in the era of immunotherapy: a narrative review.

Background and Objective: Immune checkpoint inhibitor (ICI)-based therapy has achieved impressive success in various cancer types. Several ICIs have been unprecedentedly approved as the treatment regimens for advanced hepatocellular carcinoma (HCC) in recent decade. Meanwhile, numerous clinical trials are being performed to exploit more ICIs into initially unresectable HCC and postoperative HCC to expectantly induce adequate tumor downstaging for further resection or implement adjuvant treatment for relapse-free survival, respectively. In this review, we aim to summarize some pragmatic histomorphologic, immunohistochemical, and molecular pathologic parameters which promisingly indicate the response of neoadjuvant/conversion ICI-related therapy and predict the efficacy of adjuvant/therapeutic ICI-related therapy for HCC. Methods: We searched PubMed using the terms hepatocellular carcinoma, immunotherapy, immune checkpoint inhibitor, immune checkpoint blockade, conversion therapy, neoadjuvant therapy, adjuvant therapy, biomarker, pathologic evaluation, pathologic assessment till February 2023. Key Content and Findings: Although there is no consensus regarding the pathologic evaluation of relevant HCC specimens, it is encouraging that a few of studies have concentrated on this field, and moreover, the methods and parameters noted on other cancer types are also worthy of reference. For the pathologic assessment of HCC specimens underwent immunotherapy, a suitable sampling scheme, identifying immunotherapy-related pathologic response, and quantification of pathologic response rate should be emphasized. For the patients of HCC who are scheduled to receive immunotherapy, tumor-infiltrating lymphocyte, intratumoral tertiary lymphoid structure, programmed cell death ligand 1, Wnt/ß-catenin, microsatellite instability and mismatch repair, tumor mutational burden and tumor neoantigen, as well as some other signaling pathways are the potential predictive biomarkers of treatment response of ICI. Conclusions: The management of HCC in the era of immunotherapy arises a brand-new pathological challenge that is to provide an immunotherapy-related diagnostic report. Albeit many related researches are preclinical or insufficient, they may tremendously alter the immunotherapy strategy of HCC in future.

Asymmetrical Interactions between Ni Single Atomic Sites and Ni Clusters in a 3D Porous Organic Framework for Enhanced CO2 Photoreduction.

3D porous organic frameworks, which possess the advantages of high surface area and abundant exposed active sites, are considered ideal platforms to accommodate single atoms (SAs) and metal nanoclusters (NCs) in high-performance catalysts; however, very little research has been conducted in this field. In the present work, a 3D porous organic framework containing Ni1 SAs and Nin NCs is prepared through the metal-assisted one-pot polycondensation of tetraaldehyde and hexaaminotriptycene. The single metal sites and metal clusters confined in the 3D space created a favorable micro-environment that facilitated the activation of chemically inert CO2 molecules, thus promoting the overall photoconversion efficiency and selectivity of CO2 reduction. The 3D-NiSAs/NiNCs-POPs, as a CO2 photoreduction catalyst, demonstrated an exceptional CO production rate of 6.24 mmol g-1 h-1, high selectivity of 98%, and excellent stability. The theoretical calculations uncovered that asymmetrical interaction between Ni1 SAs and Nin NCs not only favored the bending of CO2 molecules and reducing the CO2 reduction energy, but also regulated the electronic structure of the catalyst leading to the optimal binding strength of intermediates.