1. Introduction

In today's world, the digital economy and sustainable development have become the focus of global social and economic transformation. The rapid development of digital technologies and the introduction of the Sustainable Development Goals provide people with all the opportunities that lie ahead, while, at the same time, posing a series of serious challenges. The intersection of these two areas not only shapes our present but will also profoundly affect our future.

The digital economy, as a result of the widespread application of information and communication technologies in various fields, is transforming the way people live, do business, and interact with society. Digitalisation has not only reshaped the way businesses operate but has also given rise to new industries and innovative business models. From big data analytics to artificial intelligence (AI), from the Internet of Things to blockchain, the digital economy is leading people into a brand new era [1]. On the one hand, the digital economy provides a new impetus for economic growth, leading to more efficient and smarter operations in all areas of society. On the other hand, the wave of digitisation has also brought about a series of problems, including the digital divide, privacy security, and structural changes in employment, which are directly related to the sustainable development of society [2].

Global sustainable development is facing increasing challenges, including climate change, resource depletion, and social inequality. The United Nations Sustainable Development Goals (SDGs) were proposed to address these challenges and build a more just, inclusive, and sustainable future [3]. However, the realisation of these goals requires concerted global action and the help of science, technology, and innovation, of which the digital economy is an important force.

The purpose of this paper is to provide insight into the interrelationship between the digital economy and sustainable development. The author explores how the digital economy affects various aspects of sustainable development, including the environment, society, and economy. Through in-depth research, this study aims to reveal the potential impacts of the digital economy on sustainable development, as well as find innovative ways in which digital technologies can contribute to sustainable development. This paper is divided into several parts, firstly, it sorts out the definition and background of the digital economy and sustainable development; secondly, it analyses in depth the challenges and opportunities that the digital economy brings to sustainable development. Then, it explores how the digital economy can support the realisation of the SDGs and how sustainable development can guide the direction of the digital economy. Finally, through case studies and by looking ahead, this paper draws some conclusions about the convergence of the digital economy and sustainable development and suggests directions for future research. At this moment of convergence between digitalisation and sustainable development, there is an urgent need to delve deeper into the interactions between the two in order to achieve the goal of a win-win situation for economic prosperity, social justice, and environmental sustainability.

2. Background and Development of the Digital Economy

2.1. Definition and Scope of the Digital Economy

The digital economy refers to a new type of economic form based on digital technology and the Internet, using computers, the Internet, big data, cloud computing, artificial intelligence, and other information technology means to carry out socio-economic activities. In the digital economy, information and data become the factors of production, and the innovation and application of digital technology continue to promote economic development and transformation. In scope, the digital economy covers many fields such as e-commerce, financial technology, smart city, digital media, Internet of Things (IoT), cloud computing, and artificial intelligence. The development of the digital economy has not only changed the business model and market pattern of traditional economic industries but also promoted the rise and development of new industries [4].

2.2. Global Trends in the Digital Economy

In terms of global trends, the development of the digital economy has shown several important trends. The first is the increase in digitisation. More and more economic activities has shifted from traditional methods to digital platforms, and online consumption, online payments, and digital currencies have penetrated into people's daily lives. The second is data-driven economic growth. The application of big data drives innovation and intelligent development of the economy, breaking down information barriers and improving resource allocation efficiency. It is the technological revolution represented by artificial intelligence, and the breakthroughs in machine learning, natural language processing, image recognition, and other technologies have given machines the ability to be intelligent, bringing about innovations in productivity and changes in the labour market. The last is the formation of the digital industry chain. The development of the digital economy has led to the digital transformation of the entire industry chain, from product design, manufacturing, marketing, and promotion to distribution and sales, each link in the industry chain can achieve efficient collaboration and intelligent management through digital technology.

2.3. Applications of the Digital Economy in Various Fields

In terms of applications in various fields, the impact of the digital economy has permeated almost all areas of the economy. In the field of e-commerce, the rise of e-commerce giants such as Alibaba and Amazon has changed the pattern of traditional retailing, with online shopping and e-commerce platforms becoming the main choice for consumers. The development of fintech has made modern finance more convenient and efficient, with mobile payments, online lending, and virtual currencies becoming emerging businesses in the financial sector. The construction of smart cities has made use of IoT and big data technologies to achieve intelligent management and optimisation of urban resources, improving the efficiency of urban operations and the quality of life. In addition, the application of the digital economy can be seen in various fields including manufacturing, culture and entertainment, healthcare, etc., injecting a new impetus to the transformation and development of the economy [5].

In conclusion, the digital economy, as a new type of economic form, has shown a trend of rapid development globally. Through the application of digital technology and the Internet, the digital economy is changing the operation mode and market pattern of the traditional economy. With the continuous innovation and application of technology, the digital economy will continue to play a great potential and role in various fields.

3. Challenges of the Digital Economy for Sustainable Development

3.1. Environmental Challenges: E-waste, Energy Consumption

The digital economy, which is centred on information and data, consumes a great deal of energy and resources in its actual operation. Data centres require large amounts of electricity to run their servers and store data. At the same time, the mass production and updating of electronic products generates a large amount of e-waste, which puts enormous pressure on the environment and triggers the rapid depletion of resources, including the overuse of scarce materials and the waste of energy. These environmental and resource pressures create a strong link between the digital economy and sustainable development.

3.2. Social Challenges: Digital Divide, Digital Privacy

The rapid growth of the digital economy has exacerbated the widening of the digital divide, especially in developing countries and poor regions. This phenomenon has led to information and technological inequalities, as the level of access to digital devices is not sufficient to meet the needs of all. At the same time, the chaotic use and misuse of personal data pose a great threat to information privacy. There is a lack of transparency and compliance in the collection and analysis of user data by large technology companies, which leads to the violation of users' right to privacy. These issues make the protection of personal data privacy and rights an urgent task in sustainable development [6].

3.3. Economic Challenges: Inequalities in the Digital Economy

With the rapid development and wide application of technologies such as artificial intelligence, big data, and cloud computing, many traditional industries are experiencing unprecedented impact and change. Advances in automation and intelligence have put many traditional jobs at risk of being replaced, such as couriers and warehouse managers. At the same time, traditional industries are also under pressure to undergo digital transformation, including brick-and-mortar retail and tourism. These challenges have not only had a significant impact on the job market but have also put some pressure on social stability and economic development.

4. Opportunities for Sustainable Development in the Digital Economy

4.1. Economic Opportunity: Digitalisation for Growth and Innovation

Digital technologies and tools have greatly increased the potential for economic efficiency and productivity. The application of automation and intelligence has made traditional production processes more efficient, reducing costs and resource use. For example, the adoption of robotics has made production lines in manufacturing more efficient and precise, while the services of drones in logistics have increased the efficiency of transport. In addition, the use of data analytics and decision-making optimisation has provided companies with more accurate market analysis and decision-making support, thereby enhancing their competitiveness and economic efficiency. The application of these digital technologies has opened up new paths and means for sustainable economic development.

4.2. Environmental Opportunities: Digital Innovation and Environmental Sustainability

The rapid development of the digital economy has given rise to emerging economic models such as the sharing economy and the circular economy, which have brought about entirely new opportunities for sustainable development. The sharing economy makes use of Internet technology to facilitate the sharing and efficient use of resources, effectively reducing the waste and depletion of resources. For example, the rise of models such as bike-sharing and office-sharing has changed people's views on resource ownership. The circular economy emphasises the recycling of resources and the reuse of waste, further reducing reliance on natural resources [7]. For example, the recycling of recycled leather and the recycling of production have significantly increased the efficiency of resource utilisation. These new economic models provide entirely new ways and modes of sustainable development, making economic development more environmentally friendly and sustainable.

4.3. Social Opportunities: Digital Inclusion and Social Equity

The rapid rise of the digital economy offers a wealth of social opportunities for sustainable development, with digital inclusion and social equity as key focal points. The widespread use of digital technologies has broken down the barriers to information access in traditional societies, providing more equal opportunities for people from all walks of life. Through the proliferation of smartphones and the Internet, information transfer has become faster and more accessible, thus narrowing the digital divide between different social groups. This has led to the concept of digital inclusion, which is to ensure that the spread of digital technologies benefits all levels of society, urban and rural, developed and developing.

At the same time, the digital economy creates new opportunities for social equity. Through digital platforms, individuals and small businesses were able to participate more broadly in the market economy, breaking down the barriers of traditional industries. This open and inclusive digital economy environment provides more opportunities for entrepreneurs and startups, thereby promoting economic diversification and sustainability [8]. Thus, with the power of the digital economy, people have the opportunity to realise a more inclusive and just society and to ensure that the dividends of scientific and technological development benefit all members of society.

5. Case Study: Intelligent Transport Systems (ITS) in Singapore

As a leader in sustainable urban development, Singapore has successfully used Intelligent Transport Systems (ITS) to address the transport challenges facing the city, providing useful lessons for other cities. In Singapore, the application of ITS has profoundly changed the city's transport landscape. Through real-time data monitoring and intelligent traffic signal control, Singapore has successfully improved road utilisation and reduced traffic congestion. This system collects and analyses traffic flow data in a timely manner, enabling intelligent signal adjustments to optimise traffic flow and ease congestion. Meanwhile, the Intelligent Parking System (IPS) helps drivers to locate vacant parking spaces, reducing the time and fuel consumption spent on searching for parking spaces.

Through ITS, Singapore has achieved efficient integration of multiple modes of transport, including the MRT, buses, and bike sharing. This integrated transport planning enables citizens to choose different modes of transport more conveniently and quickly, reducing the need for personal cars and thus mitigating the adverse impact of transport on the environment. In addition, Singapore's ITS system provides emergency response and management to ensure that the city is able to respond quickly in the event of an emergency, such as an accident or natural disaster, improving the city's ability to handle emergencies [9].

The success of Singapore's ITS emphasises the key role of digital technology in addressing urban challenges. By making full use of data and intelligent systems, cities can better plan and manage transport, increase resource efficiency, and improve the quality of life for residents. This case provides inspiration for other cities and has stimulated widespread interest in and adoption of intelligent transport systems. Demonstrates the positive interaction between the digital economy and sustainable urban development. Through technological innovation and digitalisation, cities are able to manage resources more efficiently, improve the quality of life, and achieve the goal of sustainable development.

6. Future Prospects and Recommendations

6.1. Future Trends in the Digital Economy

The future development trend of the digital economy will show profound changes and innovations in several aspects. First, the widespread application of artificial intelligence will drive the digital economy to a higher level. The continuous advancement of AI technologies such as machine learning, natural language processing, and computer vision will enable digital systems to understand and adapt to changing environments more intelligently and provide more personalised and precise services.

Second, the emergence of blockchain technology will inject new vigour into the digital economy. The decentralisation and security features of blockchain make digital transactions more transparent and reliable, thus accelerating the development of the digital economy. Blockchain applications such as smart contracts and digital identity verification will also provide more efficient infrastructure and services for the digital economy.

Third, the popularity of the Internet of Things will further deepen the integration of the digital economy with the physical world. The interconnection of various types of devices and sensors will build a smart, interactive ecosystem that will provide smarter solutions in areas such as production, transport, and health. The development of IoT will further expand the boundaries of the digital economy and promote the penetration of digitalisation and innovation at all levels of society. In addition, sustainable development will become an important direction for the digital economy. Innovations in digital technologies will be channelled to address global sustainability challenges, including energy management, environmental monitoring, carbon emission control, and so on. The digital economy is expected to be a key tool for achieving a balance between economic prosperity and environmental protection.

Overall, the future development of the digital economy will present increasingly complex and diverse trends at the technological, application, and societal levels, bringing about entirely new development opportunities and challenges for the global economic system.

6.2. How to Better Integrate the Digital Economy and Sustainable Development

How to better integrate the digital economy and sustainable development is an important issue in the development of today's society. First, a strong regulatory framework is needed at the policy level to steer the development of the digital economy in a sustainable direction. This involves clear environmental, social responsibility and sustainability criteria to ensure that the process of digitisation does not have an irreversible impact on the environment while promoting social equity and inclusion. Second, incentivising the innovation and application of digital technologies is essential for integrating the digital economy with sustainable development. By supporting environmentally friendly technologies, digital applications of renewable energy, etc., the needs of sustainable development can be better met in the development of the digital economy. Governments and businesses should work together to invest in green technologies and digital solutions that address sustainability challenges. In addition, digital education is a key component. Raising the level of public awareness of digital technologies and developing the skills needed in the digital age can ensure that more people are able to participate in the development of the digital economy and promote social inclusion.

Public-private partnerships are also an effective way to integrate the digital economy with sustainable development. Through close co-operation between business and government, people can work together to address challenges in the environmental, social, and economic spheres and achieve the SDGs. Co-investment, technology sharing, and information exchange are all ways to promote the integration of the digital economy and sustainable development. Finally, incentive mechanisms and certification systems should be established to motivate businesses to adopt sustainable digital practices. By setting up economic incentives, reward mechanisms, and certification systems, companies can be guided to pay more attention to sustainability in digital development and provide them with recognition for their positive behaviours [10]. In integrating the digital economy and sustainable development, there is a need to continuously seek opportunities for innovation, cooperation, and win-win situations to ensure that the driving force of digitisation and the concept of sustainable development are mutually reinforcing, thus laying a solid foundation for a sustainable economy in the future.

7. Conclusion

While the rapid development of digital technologies is shaping the economic landscape of the future, it also brings with it a series of challenges and opportunities. First, this paper realises that the digital economy has far-reaching implications at the environmental, social, and economic levels. It has had a significant impact on the efficient use of resources, the transformation of production patterns, and the shaping of social structures. However, the rapid development of the digital economy is also accompanied by problems such as energy consumption, environmental pressures, and the digital divide, which require people to find innovative solutions to achieve the goals of sustainable development.

Secondly, the strong link between the digital economy and sustainable development highlights the urgency of international cooperation. In the face of global challenges, countries need to strengthen cooperation, share best practices, and work together to address issues in the development of digital technology. International organisations and governments play a key role in setting global standards, regulations, and policies to ensure the sustainability of the digital economy.

It is necessary to pursue synergy and co-creation at the intersection of the digital economy and sustainability. Moreover, it is expected to shape a future where the digital economy and sustainability are mutually reinforcing by developing smart policies, encouraging innovation, and strengthening international collaboration. This will require concerted efforts to make the power of digitisation a true enabler of a sustainable future, with shared economic, social, and environmental prosperity.