Advance of Near-Infrared Emissive Carbon Dots in Diagnosis and Therapy: Synthesis, Luminescence, and Application.

Carbon dots (CDs) with good optical properties, biocompatibility, easy functionalization, and small size have attracted more and more attention and laid a good foundation for their applications in the biomedicine field. CDs emitted in near-infrared regions (NIR-CDs) can achieve high penetration depth imaging and produce high cytotoxic substance for disease treatment. Therefore, NIR-CDs are promising materials to realize high-quality imaging-guided diagnostic and therapeutic integration. This review first introduces the current mainstream synthesis methods of NIR-CDs by "top-down" and "bottom-up". Second, the luminescence modes of NIR-CDs are introduced, and the luminescence mechanisms based on carbon core state, surface state, molecular state, and crosslinking enhanced emission are summarized. Third, the applications and principles of NIR-CDs in imaging, drug delivery, and non-invasive therapeutics are introduced from a view of diagnosis and therapy. Finally, their prospects and challenges in biomedical and biotechnological applications are outlined.

Dual-Polymer Functionalized Melanin-AgNPs Nanocomposite with Hydroxyapatite Binding Ability to Penetrate and Retain in Biofilm Sequentially Treating Periodontitis.

Periodontitis is the leading cause of adult tooth missing. Thorny bacterial biofilm and high reactive oxygen species (ROS) levels in tissue are key elements for the periodontitis process. It is meaningful to develop an advanced therapeutic system with sequential antibacterial/ antioxidant ability to meet the overall goals of periodontitis therapy. Herein, a dual-polymer functionalized melanin-AgNPs (P/D-MNP-Ag) with biofilm penetration, hydroxyapatite binding, and sequentially treatment ability are fabricated. Polymer enriched with 2-(Dimethylamino)ethyl methacrylate (D), can be protonated in an acid environment with enhanced positive charge, promoting penetration in biofilm. The other polymer is rich in phosphate group (P) and can chelate Ca2+, promoting the polymer to adhere to the hydroxyapatite surface. Melanin has good ROS scavenging and photothermal abilities, after in situ reduction Ag, melanin-AgNPs composite has sequentially transitioned between antibacterial and antioxidative ability due to heat and acid accelerated Ag+ release. The released Ag+ and heat have synergistic antibacterial effects for bacterial killing. With Ag+ consumption, the antioxidant ability of MNP recovers to scavenge ROS in the inflammatory area. When applied in the periodontitis model, P/D-MNP-Ag has good therapeutical effects to ablate biofilm, relieve inflammation state, and reduce alveolar bone loss. P/D-MNP-Ag with sequential treatment ability provides a reference for developing advanced oral biofilm eradication systems.

Boron-Doped Engineering for Carbon Quantum Dots-Based Memristors with Controllable Memristance Stability.

Carbon quantum dots-based memristors (CQDMs) have emerged as a rising star in data storage and computing. The key constraint to their commercialization is memristance variability, which mainly arises from the disordered conductive paths. Doping methodology can optimize electron and ion transport to help construct a stable conductive mode. Herein, based on boron (B)-doped engineering strategy, three kinds of comparable quantum dots are synthesized, including carbon quantum dots (CQDs), a series of boron-doped CQDs (BCQDs) with different B contents, and boron quantum dots. The corresponding device performances highlight the superiority of BCQDs-based memristors, exhibiting a ternary flash-type memory behavior with longer retention time and more controllable memristance stability. The comprehensive analysis results, including device performance, functional layer morphology, and material simulated calculation, illustrate that the doped B elements can directionally guide the migration of aluminum ions by enhancing the capture of free electrons, resulting in ordered conductive filaments and stable ternary memory behavior. Finally, the conceptual applications of logic display and logic gate are discussed, indicating a bright prospect for BCQDs-based memristors. This work proves that modest B doping can optimize memristance property, establishing a theoretical foundation and template scheme for developing effective and stable CQDMs.

Folic acid functionalized gadolinium-doped carbon dots as fluorescence / magnetic resonance imaging contrast agent for targeted imaging of liver cancer.

Gadolinium-doped carbon dots (Gd-CDs), as a new class of nanomaterial, has a wide application prospect in targeted imaging and monitoring diagnosis and treatment of liver cancer because of their good fluorescence (FL)-magnetic resonance (MR) imaging properties. First, Gd-CDs were synthesized by hydrothermal method with gadodiamide as gadolinium source, citric acid as carbon source and silane coupling agent (KH-792) as coupling agent with FL quantum yield (QY) of 48.2%. Then, folic acid (FA), which is highly expressed in liver cancer, was used as a targeting component to modify Gd-CDs to obtain targeted imaging agent (Gd-CDs-FA). The results showed that Gd-CDs and Gd-CDs-FA have low cytotoxicity and good biocompatibility, and the targeting and selectivity of Gd-CDs-FA to HepG2 cells could be observed under confocal laser scanning microscope (CLSM). The T1 longitudinal relaxation rates (r1) of Gd-CDs and Gd-CDs-FA are 15.92 mM-1s-1 and 13.56 mM-1s-1, respectively. They showed good MR imaging ability in vitro and in vivo, and MR imaging in nude mice further proved the targeting imaging performance of Gd-CDs-FA. Therefore, Gd-CDs-FA with higher QY showed good FL-MR targeting imaging ability of liver cancer, which broke through the limitations of single molecular imaging probe in sensitivity and soft tissue resolution. This study provides a new idea for the application of Gd-CDs in FL and MR targeting imaging of liver cancer.

Advances in Magnetic Carbon Dots: A Theranostics Platform for Fluorescence/Magnetic Resonance Bimodal Imaging and Therapy for Tumors.

Theranostics technology that combines tumor diagnosis or monitoring with therapy is an important direction for the future development of tumor treatment. It takes advantage of efficiently observing tumor tissues, monitoring tumor treatment in real time, and significantly improving the cure efficiency. Magnetic carbon dots (CDs) are of wide interest as molecular imaging probes, drug carriers, photosensitizers, and radiosensitizers in the integration of tumor fluorescence/magnetic resonance bimodal diagnosis and treatment because of their small size, good optical stability, magnetic relaxation rate, and biocompatibility. This review first analyzes and compares the synthesis methods and physicochemical properties of magnetic CDs in recent years and then concludes their mechanism in tumor fluorescence/magnetic resonance bimodal imaging and therapy in details. Subsequently, the research progress of their application in tumor theranostics are summarized. Finally, the problems and challenges of magnetic CDs for development at this stage are prospected. This review provides new ideas for their controlled synthesis and application in efficient and precise therapy for tumors.

Research progress of siVEGF complex and their application in antiangiogenic therapy.

Vascular endothelial growth factor (VEGF) is an important factor in the development of some diseases such as tumors, ocular neovascular disease and endometriosis. Inhibition of abnormal VEGF expression is one of the most effective means of treating these diseases. The resistance and side effects of currently used VEGF drugs limit their application. Herein, small interfering RNA for VEGF (siVEGF) are developed to inhibit VEGF expression at the genetic level by means of RNA interference. However, as a foreign substance entering the organism, siVEGF is prone to induce an immune response or mismatch, which adversely affects the organism. It is also subjected to enzymatic degradation and cell membrane blockage, which greatly reduces its therapeutic effect. Targeted siVEGF complexes are constructed by nanocarriers to avoid their clearance by the body and precisely target cells, exerting anti-vascular effects for the treatment of relevant diseases. In addition, some multifunctional complexes allow for the combination of siVEGF with other therapeutic tools to improve the treat efficiency of the disease. Therefore, this review describes the construction of the siVEGF complex, its mechanism of action, application in anti-blood therapy, and provides an outlook on its current problems and prospects.

One-Step Synthesis of White-Light-Emitting Carbon Dots for White LEDs with a High Color Rendering Index of 97.

White-light-emitting carbon dots (WCDs) show innate advantages as phosphors in white light-emitting diodes (WLEDs). For WLEDs, the color rendering index (CRI) is the most important metric to evaluate its performance. Herein, WCDs are prepared by a facile one-step solvothermal reaction of trimellitic acid and o-phenylenediamine. It consists of four CDs identified by column chromatography as blue, green, yellow, red, and thus white light is a superposition of these four types of light. The mixture of the four CDs undergoes Förster resonance energy transfer to induce the generation of white light. The photoluminescence of WCDs originates from the synergistic effect of carbon core and surface states. Thereinto, the carbon core states dominate in RCDs, and the increase of amide contents and degree of conjugation promote the redshift of the emission spectra, which is further confirmed by theoretical calculations. In addition, a high CRI of 97 is achieved when the WCDs are used as phosphors to fabricate WLEDs, which is almost the highest value up to now. The multicolor LEDs can also be fabricated by using the four multicolor CDs as phosphors, respectively. This work provides a novel approach to explore the rapid preparation of low-cost, high-performance WCDs and CDs-based WLEDs.

In Situ Growth of Iron Sulfide on Fast Charge Transfer V2 C-MXene for Superior Sodium Storage Anodes.

Due to the upstream pressure of lithium resources, low-cost sodium-ion batteries (SIBs) have become the most potential candidates for energy storage systems in the new era. However, anode materials of SIBs have always been a major problem in their development. To address this, V2 C/Fe7 S8 @C composites with hierarchical structures prepared via an in situ synthesis method are proposed here. The 2D V2 C-MXene as the growth substrate for Fe7 S8  greatly improves the rate capability of SIBs, and the carbon layer on the surface provides a guarantee for charge-discharge stability. Unexpectedly, the V2 C/Fe7 S8 @C anode achieves satisfactory sodium storage capacity and exceptional rate performance (389.7 mAh g-1  at 5 A g-1 ). The sodium storage mechanism and origin of composites are thoroughly studied via ex situ characterization techniques and first-principles calculations. Furthermore, the constructed sodium-ion capacitor assembled with N-doped porous carbon delivers excellent energy density (135 Wh kg-1 ) and power density (11 kW kg-1 ), showing certain practical value. This work provides an advanced system of sodium storage anode materials and broadens the possibility of MXene-based materials in the energy storage.

Cysteine-Derived Chiral Carbon Quantum Dots: A Fibrinolytic Activity Regulator for Plasmin to Target the Human Islet Amyloid Polypeptide for Type 2 Diabetes Mellitus.

The fibrillization and deposition of the human islet amyloid polypeptide (hIAPP) are the pathological hallmark of type 2 diabetes mellitus (T2DM), and these insoluble fibrotic depositions of hIAPP are considered to strongly affect insulin secretion by inducing toxicity toward pancreatic islet ß-cells. The current strategy of preventing amyloid aggregation by nanoparticle-assisted inhibitors can only disassemble fibrotic amyloids into more toxic oligomers and/or protofibrils. Herein, for the first time, we propose a type of cysteine-derived chiral carbon quantum dot (CQD) that targets plasmin, a core natural fibrinolytic protease in humans. These CQDs can serve as fibrinolytic activity regulators for plasmin to cleave hIAPP into nontoxic polypeptides or into even smaller amino acid fragments, thus alleviating hIAPP's fibrotic amyloid-induced cytotoxicity. Our experiments indicate that chiral CQDs have opposing effects on plasmin activity. The l-CQDs promote the cleavage of hIAPP by enhancing plasmin activity at a promotion ratio of 23.2%, thus protecting ß-cells from amyloid-induced toxicity. In contrast, the resultant d-CQDs significantly inhibit proteolysis, decreasing plasmin activity by 31.5% under the same reaction conditions. Second harmonic generation (SHG) microscopic imaging is initially used to dynamically characterize hIAPP before and after proteolysis. The l-CQD promotion of plasmin activity thus provides a promising avenue for the hIAPP-targeted treatment of T2DM to treat low fibrinolytic activity, while the d-CQDs, as inhibitors of plasmin activity, may improve patient survival for hyperfibrinolytic conditions, such as those existing during surgeries and traumas.

A biotin-stabilized HKUST-1/ADM scaffold for facilitating MSC endothelial differentiation and vascularization in diabetic wound healing.

Inadequate angiogenesis in diabetic wound healing has been identified as one of the most difficult issues to treat. Copper ions (Cu2+) have been confirmed to stimulate angiogenesis; nevertheless, the rapid rise in non-physiological Cu2+ concentrations increases the danger of ion poisoning. For the first time, biotin was used to stabilize a copper-based metal-organic framework (HKUST-1) to change its hydrophobicity and achieve sustained release of Cu2+. The inability to offer a suitable area for the dynamic interaction between cells and growth factors still restricts the use of nanomaterials for the regeneration of injured skin in diabetes. Acellular dermal matrix (ADM) scaffolds are collagen fibers with natural spatial tissue that can create a biological "niche" for cell attachment and growth. In this study, biotin-stabilized HKUST-1 (B-HKUST-1) nanoparticles were modified with an ADM to form a novel scaffold (ADM-B-HKUST-1). Notably, Cu2+ and mesenchymal stem cells (MSCs) released by the composite scaffold may synergistically promote MSC adhesion, proliferation and endothelial differentiation by upregulating the expression of transforming growth factor-ß (TGF-ß), vascular endothelial growth factor (VEGF) and alpha-smooth muscle actin (α-SMA). Overall, the ADM-B-HKUST1 scaffold combines the dual advantages of the sustained release of Cu2+ and creating a biological "niche" can provide a potential strategy for enhancing angiogenesis and promoting diabetic wound healing.

ZIF-8-derived N-doped hierarchical porous carbon coated with imprinted polymer as magnetic absorbent for phenol selective removal from wastewater.

Producing a desirable adsorbent with strong affinity adsorption sites, excellent selectivity properties, and the ability to easily separate solid from liquid for the removal of phenol to a permissible level remains a great challenge in wastewater treatment. Herein, an N-doped magnetic carbon skeleton is presented as a porous adsorbent matrix. Importantly, the pore volume and specific surface area of the adsorbent matrix can be meticulously tuned by adjusting the thermal treatment condition, while dispersing and immobilizing the N fraction. This would ultimately result in an N-rich matrix structure with flexible mass transfer channel. The imprinted modification generates a large number of phenol-shaped geometrical cavities on the matrix. This helps to activate the phenol recognition "awareness" of N-active sites and greatly endows the adsorbent with selective adsorption property. Due to the advantageous balance between the hierarchical porous adsorbent matrix with uniformly distributed N-active sites and the imprinted polymer, the adsorbent has a superior adsorption capacity of 995.2 mg g-1 and selective recognition (Kd = 3.92, 3.78; HQ, PTBP) towards phenol. It outperforms previously reported adsorbents. In addition, its easy magnetic separation property makes the adsorbent to have excellent reusability. The adsorbent presents a promising potential for separating pollutants from wastewater and it sheds light on the design of an efficient comprehensive adsorbent.

Recent research progress in CDs@MOFs composites: fabrication, property modulation, and application.

Carbon dots (CDs) have exhibited a promising application prospect in many fields because of their good fluorescence properties, biocompatibility, low toxicity, and easy functionalization. In order to improve their photoelectricity and stability, metal-organic frameworks (MOFs) can be used as host materials to provide ideal carriers for CDs to realize the multifunctional composites of CDs and MOFs (CDs@MOFs). At present, CDs@MOFs composites have shown tremendous application potential because they have various advantages of both CDs and MOFs. In this review, the synthesis methods of CDs@MOFs composites are firstly introduced. Then, the influence of the synergy between CDs and MOFs on the regulation of their structures and optical properties is highlighted. Furthermore, the recent application researches of CDs@MOFs composites in fluorescent probes, solid-state lighting, and photoelectrocatalysis are generalized. Finally, the critical issues, challenges, and solutions on their structure and property regulation and application are put forward, and their commercialization direction is also prospected.

Surface state modulation of blue-emitting carbon dots with high quantum yield and high product yield.

In order to explore the surface state modulation mechanism of carbon dots (CDs) with high quantum yield (QY) and high product yield (PY), CDs were synthesized from different carbon sources with different contents of oxygen-containing functional groups and different silane coupling agents with nitrogen-containing functional groups. The highest QY of as-prepared CDs can reach 97.32% and the PY values of CDs are all high ranging from 46.33-58.76%. It is found that the high content of C[double bond, length as m-dash]O and pyrrolic N on the surface of CDs can endow CDs with high QY. Moreover, the PY of CDs not only depends on whether CDs have the crosslinked structure, but also is closely and positively correlated with pyridinic N. Consequently, our findings suggest that raw materials rich in carboxyl groups and amino groups are beneficial to the synthesis of CDs with high QY, and whether CDs with crosslinked structure and high content of pyridinic N decide the high PY of CDs. This work provides a theoretical guidance for large-scale synthesis of CDs with high QY and high PY.

Carbon dots-based delayed fluorescent materials: Mechanism, structural regulation and application.

Delayed fluorescent (DF) materials have high internal quantum efficiency because of the triplet excitons involved in the radiation transition, and the spin-forbidden transition can effectively improve their luminescent lifetime. Compared with traditional afterglow materials including metal-containing inorganic coordination compounds and organic compounds, the DF materials based on carbon dots (CDs) have drawn extensive attention because of their advantages of low toxicity, environmental friendliness, stable luminescence, easy preparation and low cost. Most CDs-based DF materials can be realized by embedding CDs in matrix with covalent bonds, hydrogen bonds or/and other supramolecular interactions. Recently, matrix-free self-protective CDs-based DF materials are emerging. This review systematically summarizes the DF mechanism and structural regulation strategies of CDs-based DF materials, and the applications of CDs-based DF materials in anti-counterfeiting, information encryption, temperature sensing and other fields are introduced. Finally, the existing problems and future potentials of CDs-based DF materials are proposed and prospected.

Preparation, Properties, and Application of Graphene-Based Materials in Tissue Engineering Scaffolds.

Tissue engineering has a great application prospect as an effective treatment for tissue and organ injury, functional reduction, or loss. Bioactive tissues are reconstructed and damaged organs are repaired by the three elements, including cells, scaffold materials, and growth factors. Graphene-based composites can be used as reinforcing auxiliary materials for tissue scaffold preparation because of their large specific surface area, and good mechanical support. Tissue engineering scaffolds with graphene-based composites have been widely studied. Part of research have focused on the application of graphene-based composites in single tissue engineering. The basic principles of graphene materials used in tissue engineering are summarized in some research. Some studies emphasized the key problems and solutions urgently needed to be solved in the development of tissue engineering and discussed their application prospect. Some related studies mainly focused on the conductivity of graphene and discussed the application of electroactive scaffolds in tissue engineering. In this review, the composite materials for preparing tissue engineering scaffolds are briefly described, which emphasizes the preparation methods, biological properties, and practical applications of graphene-based composite scaffolds. The synthetic techniques, with stressing solvent casting, electrospinning, and three-dimensional printing, are introduced in detail. The mechanical, cell-oriented, and biocompatible properties of graphene-based composite scaffolds in tissue engineering are analyzed and summarized. Their applications in bone tissue engineering, nerve tissue engineering, cardiovascular tissue engineering, and other tissue engineering are summarized systematically. In addition, this work also looks forward to the difficulties and challenges in the future research, providing some references for the follow-up research of graphene-based composites in tissue engineering scaffolds. Impact statement Regeneration and repair of tissue and organ injury has become a new research hotspot in recent years. Tissue engineering scaffolds prepared with graphene-based materials have good biocompatibility, excellent mechanical properties, and strong cell orientation, which can fully induce the proliferation and differentiation of seed cells. This review briefly describes the basic materials for the preparation of tissue engineering scaffolds, and focuses on the preparation, performance, and application of graphene-based materials in tissue engineering, providing sufficient understanding of graphene applied in regenerative medicine.

Ni@Ni3N Embedded on Three-Dimensional Carbon Nanosheets for High-Performance Lithium/Sodium-Sulfur Batteries.

Lithium-sulfur (Li-S) batteries are recognized as one of the most promising next-generation energy storage devices, but their practical application is greatly limited by several obstacles, such as the highly insulating nature and sluggish redox kinetics of sulfur and the dissolution of lithium polysulfides. Herein, three-dimensional carbon nanosheet frameworks anchored with Ni@Ni3N heterostructure nanoparticles (denoted Ni@Ni3N/CNS) are designed and fabricated by a chemical blowing and thermal nitridation strategy. It is demonstrated that the Ni@Ni3N heterostructure can effectively accelerate polysulfide conversion and promote the chemical trapping of polysulfides. Meanwhile, the carbon nanosheet frameworks of Ni@Ni3N/CNS establish a highly conductive network for fast electron transportation. The cells with Ni@Ni3N heterostructures as the catalyst in the cathode show excellent electrochemical performance, revealing stable cycling over 600 cycles with a low-capacity fading rate of 0.04% per cycle at 0.5 C and high-rate capability (594 mAh g-1 at 3 C). Furthermore, Ni@Ni3N/CNS can also work well in room-temperature sodium-sulfur (RT-Na/S) batteries, delivering a high specific capacity (454 mAh g-1 after 400 cycles at 0.5 C). This work provides a rational way to prepare the metal-metal nitride heterostructures to enhance the performance both of Li-S and RT-Na/S batteries.

Research Progress in the Synthesis of Targeting Organelle Carbon Dots and Their Applications in Cancer Diagnosis and Treatment.

With increasing knowledge about diseases at the histological, cytological to sub-organelle level, targeting organelle therapy has gradually been envisioned as an approach to overcome the shortcomings of poor specificity and multiple toxic side effects on tissues and cell-level treatments using the currently available therapy. Organelle carbon dots (CDs) are a class of functionalized CDs that can target organelles. CDs can be prepared by a "synchronous in situ synthesis method" and "asynchronous modification method." The superior optical properties and good biocompatibility of CDs can be preserved, and they can be used as targeting particles to carry drugs into cells while reducing leakage during transport. Given the excellent organelle fluorescence imaging properties, targeting organelle CDs can be used to monitor the physiological metabolism of organelles and progression of human diseases, which will provide advanced understanding and accurate diagnosis and targeted treatment of cancers. This study reviews the methods used for preparation of targeting organelle CDs, mechanisms of accurate diagnosis and targeted treatment of cancer, as well as their application in the area of cancer diagnosis and treatment research. Finally, the current difficulties and prospects for targeting organelle CDs are prospected.

Preparation of nitrogen-doped hollow carbon nanosphere/graphene composite aerogel for efficient removal of quinoline from wastewater.

The deep removal of quinoline from coking wastewater is a prerequisite for reducing its potential threat to environmental safety. Therefore, it is urgent to develop advanced materials for efficient removal of quinoline in wastewater. In this work, a nitrogen-doped hollow carbon nanosphere/graphene composite aerogel (HCNS/NGA) was prepared by in-situ reduction self-assembly strategy, in which HCNS prevents the agglomeration of graphene oxide (GO) nanosheets, and a special sphere-sheet mutual support structure is formed to ensure the structural stability. As-prepared HCNS/NGA exhibits large specific surface area, hierarchical pore structure, and excellent conductivity. Large cavity inside and hierarchically porous structure that primarily consists of micropores, resulting in high quinoline adsorption performance (138.37 ± 2.58 mg g-1 at 298 K). Furthermore, in a fixed-bed column adsorption system, the partition coefficient at 10% breakthrough reaches up to 35.19 mg g-1 µM-1. More importantly, HCNS/NGA, as a conductive monolithic sorbent, can realize easy solid-liquid separation, as well as efficient regeneration in situ by electrochemically assisted regeneration. After ten regeneration cycles, the adsorption capacity retention is 91.54%. In short, as an efficient adsorbent, HCNS/NGA has an enormous application potential in wastewater treatment.

Endogenous H2O2-Sensitive and Weak Acidic pH-Triggered Nitrogen-Doped Graphene Nanoparticles (N-GNMs) in the Tumor Microenvironment Serve as Peroxidase-Mimicking Nanozymes for Tumor-Specific Treatment.

Nanozymes are emerging as a promising strategy for the treatment of tumors. Herein, to cope with the tumor microenvironment (TME), weak acidity (pH 5.6 to 6.8) and trace amounts of overexpressed hydrogen peroxide (H2O2) (100 µM-1 mM), we report nitrogen-doped graphene nanomaterials (N-GNMs), which act as highly efficient catalytic peroxidase (POD)-mimicking nanozymes in the TME for tumor-specific treatment. N-GNMs exhibit POD catalytic properties triggered by a weakly acidic TME and convert H2O2 into highly toxic hydroxyl radicals (•OH) thus causing the death of tumor cells while in the neutral pH surroundings of normal tissues, such catalysis is restrained and leaves normal cells undamaged thereby achieving a tumor-specific treatment. N-GNMs also display a high catalytic activity and can respond to the trace endogenous H2O2 in the TME resulting in a high efficiency of tumor therapy. Our in vitro chemical and cell experiments illustrated the POD-like activity of N-GNMs and in vivo tumor model experiments confirmed the significant inhibitory effect of N-GNMs on tumor growth.

Effect of Surfactant Polyvinyl Pyrrolidone on the Properties of Microporous Carbon Nanospheres Reinforced Magnesium Matrix Composites.

Microporous carbon nanospheres (PCNS)-reinforced magnesium (Mg) composites were prepared using polyvinyl pyrrolidone (PVP) as surfactant and PCNS as reinforcement. The influence of PVP treatment and the effectiveness of PCNS on the mechanical properties of Mg-based composites were investigated. The results show that the PCNS can enhance the properties of the Mg matrix. Moreover, the PVP can effectively improve the dispersion of PCNS in the Mg matrix but had a negative influence on the tensile properties of composites. The MgO films with high tensile strength were produced between matrix and reinforcement after removing PVP, which effectively promotes the interface compatibility and improves the properties of the composite. The tensile yield strength and specific strength of PCNS-reinforced Mg matrix composite exhibited 177 MPa and 102.4 × 103 N∙m/kg, respectively, which were 77% and 78% higher than those of the Mg matrix.